Piero, João V B Del; Miwa, Roberto H.; Scopel, Wanderlã L. Vanadium incorporation in 2D-layered MoSe2 Journal Article Em: J. Phys.: Condens. Matter, vol. 37, não 4, 2025, ISSN: 1361-648X. Resumo | Links | BibTeX | Tags: Kaewmaraya, T.; Amorim, Rodrigo G.; Thatsami, N.; Moontragoon, P.; Pinitsoontorn, S.; Bae, H.; Lee, H.; Nasiri, N.; Hussain, T. Highly efficient room-temperature ethylene sensing with molybdenum based transition metal dichalcogenides Journal Article Em: Applied Surface Science, vol. 697, 2025, ISSN: 0169-4332. Villegas, Cesar E. P.; Jr, Enesio Marinho; Dias, A. C.; Venezuela, Pedro; Rocha, Alexandre Reily Optical properties of TiS3 as a novel thin film for single-junction and tandem solar cells Working paper 2025. Resumo | Links | BibTeX | Tags: Victor, Rodrigo Torrão; Safeer, Syed Hamza; Marroquin, John F. R.; Costa, Marcio; Felix, Jorlandio F.; Carozo, Victor; Sampaio, Luiz C.; Garcia, Flavio Disentangling edge and bulk spin-to-charge interconversion in MoS2 monolayer flakes Journal Article Em: Nat Commun, vol. 16, não 1, 2025, ISSN: 2041-1723. Resumo | Links | BibTeX | Tags: Spalenza, Pedro Elias Priori; de Souza, Fábio Arthur Leão; Amorim, Rodrigo G.; Villegas, César E. P.; Pandey, Ravindra; Scopel, Wanderlã L. Fast recovery and ultrasensitive net-graphene sensor for monitoring SF<mml:math xmlns:mml= Journal Article Em: Applied Surface Science, vol. 698, 2025, ISSN: 0169-4332. Resumo | Links | BibTeX | Tags: Neto, Antonio M.; Valeriano, Maycom C.; Temperini, Marcia L. A.; Homem-de-Mello, Paula; Mamián-López, Mónica B. Improving 5-halouracils SERS detection driven by Watson & Crick pairing recognition. A spectroscopic & DFT study Journal Article Em: Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, vol. 337, 2025, ISSN: 1386-1425. Resumo | Links | BibTeX | Tags: Fujisawa, Kazunori; Carvalho, Bruno R.; Venezuela, Pedro; Kang, Cheon-Soo; Kim, Yoong Ahm; Hayashi, Takuya; Terrones, Mauricio 2025. Resumo | Links | BibTeX | Tags: Luna, Wilson Nieto; Smeyers, Robin; Sevik, Cem; Covaci, Lucian; Milošević, Milorad V. 2025. Resumo | Links | BibTeX | Tags: Pedrosa, Renan Narciso; Villegas, Cesar E. P.; Rocha, Alexandre Reily; Amorim, Rodrigo G.; Scopel, Wanderlã L. Interlayer Excitons and Radiative Lifetimes in MoSe2/SeWS Bilayers: Implications for Light-Emitting Diodes Journal Article Em: ACS Appl. Nano Mater., vol. 8, não 10, pp. 5051–5058, 2025, ISSN: 2574-0970. Resumo | Links | BibTeX | Tags: Dias, Victor M. S. C.; Kuritza, Danilo P.; Oliveira, Igor S. S.; Padilha, Jose E.; Miwa, Roberto H. Catenary-like rippled biphenylene/graphene lateral heterojunction Working paper 2025. Resumo | Links | BibTeX | Tags: Oliveira, P. R. A; Lima, L.; Felix, G.; Venezuela, Pedro; Stavale, F. Formation mechanism, stability and role of zinc and sulfur vacancies on the electronic properties and optical response of ZnS Working paper 2025. Resumo | Links | BibTeX | Tags: Cysne, Tarik P.; Canonico, Luis M.; Costa, Marcio; Muniz, R. B.; Rappoport, Tatiana G. Orbitronics in Two-dimensional Materials Working paper 2025. Resumo | Links | BibTeX | Tags: Cardias, R.; Bergman, Anders; Strand, Hugo U. R.; Muniz, R. B.; Costa, Marcio Edge non-collinear magnetism in nanoribbons of Fe3GeTe2 and Fe3GaTe2 Working paper 2025. Resumo | Links | BibTeX | Tags: Goswami, Saswata; Oliveira, Caique Campos; Ipaves, Bruno; Mahapatra, Preeti Lata; Pal, Varinder; Sarkar, Suman; Autreto, Pedro A. S.; Ray, Samit K.; Tiwary, Chandra Sekhar Exceptionally High Nonlinear Optical Response in Two-dimensional Type II Dirac Semimetal Nickel di-Telluride (NiTe2) Working paper 2025. Resumo | Links | BibTeX | Tags: Ipaves, Bruno; Justo, João F.; de Almeida, James M.; Assali, Lucy V. C.; Autreto, Pedro A. S. Enhancing catalyst activity of two-dimensional C4N2 through doping for the hydrogen evolution reaction Working paper 2025. Resumo | Links | BibTeX | Tags: Shafiei, Mohammad; Milošević, Milorad V. Light-induced dissipationless states in magnetic topological insulators with hexagonal warping Working paper 2025. Resumo | Links | BibTeX | Tags: Serquen, E.; Lizárraga, K.; Enrique, L. A.; Bravo, F.; Mishra, S.; LLontop, P.; Venezuela, Pedro; Tessler, L. R.; Guerra, J. A. 2025. Resumo | Links | BibTeX | Tags: Šabani, Denis; Bacaksız, Cihan; Milošević, Milorad V. Beyond the orbitally-resolved magnetic exchange in CrI3 and NiI2 Working paper 2025. Resumo | Links | BibTeX | Tags: Orenstein, Rachel; Ciesielski, Kamil; Synoradzki, Karol; Qu, Jiaxing; Bipasha, Ferdaushi Alam; Gomes, Lidia C.; Adamczyk, Jesse M.; Berger, Shannon; Ertekin, Elif; Toberer, Eric S. Complex thermoelectric transport in Bi-Sb alloys Journal Article Em: vol. 12, não 1, 2025, ISSN: 1931-9401. Resumo | Links | BibTeX | Tags: Rajeev, Karthik; Ipaves, Bruno; de Oliveira, Caique Campos; Raman, Sreeram Punathil; Kar, Swastik; Galvao, Douglas S; Autreto, Pedro A. S.; Tiwary, Chandra Sekhar Enhanced Non‐Invasive Radio Frequency Heating Using 2D Pyrite (Pyritene) Journal Article Em: Small Methods, 2025, ISSN: 2366-9608. Resumo | Links | BibTeX | Tags: @article{DelPiero2024,
title = {Vanadium incorporation in 2D-layered MoSe2},
author = {João V B Del Piero and Roberto H. Miwa and Wanderlã L. Scopel},
url = {https://iopscience.iop.org/article/10.1088/1361-648X/ad8abb/meta},
doi = {10.1088/1361-648x/ad8abb},
issn = {1361-648X},
year = {2025},
date = {2025-11-11},
urldate = {2025-01-27},
journal = {J. Phys.: Condens. Matter},
volume = {37},
number = {4},
publisher = {IOP Publishing},
abstract = {Recent advances in experimental techniques have made it possible to manipulate the structural and electronic properties of two-dimensional layered materials (2DM) through interaction with foreign atoms. Using quantum mechanics calculations based on the density functional theory, we explored the dependency of the structural, energetic, electronic, and magnetic properties of the interaction between Vanadium (V) atoms and monolayer and bilayer MoSe2. Spin-polarized metallic behavior was observed for high V concentration, and a semiconductor/metal interface emerged due to V adsorption on top of BL MoSe2. Our research demonstrated that the functionalization of 2D materials makes an important contribution to the design of spintronic devices based on a 2D-layered materials platform.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
@article{Kaewmaraya2025,
title = {Highly efficient room-temperature ethylene sensing with molybdenum based transition metal dichalcogenides},
author = {T. Kaewmaraya and Rodrigo G. Amorim and N. Thatsami and P. Moontragoon and S. Pinitsoontorn and H. Bae and H. Lee and N. Nasiri and T. Hussain},
doi = {10.1016/j.apsusc.2025.162984},
issn = {0169-4332},
year = {2025},
date = {2025-07-00},
urldate = {2025-07-00},
journal = {Applied Surface Science},
volume = {697},
publisher = {Elsevier BV},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
@workingpaper{villegas2025opticalpropertiestis3novel,
title = {Optical properties of TiS3 as a novel thin film for single-junction and tandem solar cells},
author = {Cesar E. P. Villegas and Enesio Marinho Jr and A. C. Dias and Pedro Venezuela and Alexandre Reily Rocha},
url = {https://arxiv.org/abs/2504.06368},
year = {2025},
date = {2025-04-08},
urldate = {2025-01-01},
abstract = {Sub-micrometer thin films are promising platforms for emerging flexible photovoltaic devices. Although the current market already produces efficient solar cells, the average wafer thickness of these devices remains far from the sub-micrometer scale, making them susceptible to cracking under bending stress and thus precluding their use in flexible device applications. Due to its earth abundance, non-toxicity, and low elastic modulus, titanium trisulfide (TiS3) has emerged as a promising alternative for flexible device applications. Here, using excited-state density functional calculations combined with the transfer matrix approach, we perform an optical analysis and assess the efficiency of a prototype photovoltaic device based on sub-micrometer TiS3 thin films. Using optical constants obtained from our first-principles calculations, we evaluate the photovoltaic response of a single-junction device in the radiative limit, finding that a 140-nm-thick active layer achieves a maximum power conversion efficiency of approximately 22%. Additionally, we investigate tandem solar cells that incorporate TiS3 into perovskite thin films, and find that the lower and upper power conversion efficiencies range from approximately 18% to 33%. Overall, our results suggest great potential for using TiS3 thin films as an active layer in the design of highly efficient flexible solar cells.},
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@article{Victor2025,
title = {Disentangling edge and bulk spin-to-charge interconversion in MoS2 monolayer flakes},
author = {Rodrigo Torrão Victor and Syed Hamza Safeer and John F. R. Marroquin and Marcio Costa and Jorlandio F. Felix and Victor Carozo and Luiz C. Sampaio and Flavio Garcia},
doi = {10.1038/s41467-025-58119-4},
issn = {2041-1723},
year = {2025},
date = {2025-03-30},
urldate = {2025-12-00},
journal = {Nat Commun},
volume = {16},
number = {1},
publisher = {Springer Science and Business Media LLC},
abstract = {Semiconductor transition metal dichalcogenides are an archetype for spintronic devices due to their spin-to-charge interconversion mechanisms. However, the exact microscopic origin of this interconversion is not yet determined. In our study, we investigated light-induced spin pumping in YIG/MoS2 heterostructures. Our findings revealed that the MoS2 monolayer microsized flakes contribute to spin current injection through two distinct mechanisms: metallic edge states and semiconductor area states. The competition between these mechanisms, influenced by the flake size, leads to different behaviors of spin-pumping. Our calculations of the local density of states, by means of density functional theory, of a flake show that light-driven spin current injection can be controlled based on the intensity of light with a suitable wavelength. We demonstrate that a lightdriven spin current injection can enhance up to very high values, attenuate, or even switch on/off the spin-to-charge interconversion. These results hold promise for developing low energy-consuming opto-spintronic device applications.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
@article{Spalenza2025,
title = {Fast recovery and ultrasensitive net-graphene sensor for monitoring SF
doi = {10.1016/j.apsusc.2025.163006},
issn = {0169-4332},
year = {2025},
date = {2025-03-30},
urldate = {2025-07-00},
journal = {Applied Surface Science},
volume = {698},
publisher = {Elsevier BV},
abstract = {Power industry insulator sulfur hexafluoride (SF) has excellent dielectric properties. However, SF decomposes into by-products over time, making their detection essential for power device evaluation and fault prevention. Recently, 2D materials, especially carbon-based ones, have become excellent gas sensing platforms, expected to lead the next generation of sensors. Because graphitic materials and SF decomposition products have weak van der Waals interactions, functionalization has been the most promising way to improve surface-molecule interactions, but it also presents experimental challenges. We propose monitoring SF degradation with a pristine net-graphene nanosensor to address these issues. Here, density functional theory and non-equilibrium Green’s functions methods are used to study the interaction between net-graphene device and gas-insulated switchgear atmosphere gas (SF, CO, N, H2O, and O), as well as the decomposition products of SF. These molecules are physisorbed on net-graphene, causing p-type doping in the device. The system’s conductance is modulated by molecule-net-graphene interactions, allowing target molecule detection and identification. We propose a field-effect device that can sense SO and HS without cross-selectivity and with a fast recovery time. It is also resistant to O and HO degradation. We found that net-graphene is a promising nanomaterial for real-time monitoring of power industry SF decomposition by-products.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
@article{Neto2025,
title = {Improving 5-halouracils SERS detection driven by Watson & Crick pairing recognition. A spectroscopic & DFT study},
author = {Antonio M. Neto and Maycom C. Valeriano and Marcia L.A. Temperini and Paula Homem-de-Mello and Mónica B. Mamián-López},
doi = {10.1016/j.saa.2025.126091},
issn = {1386-1425},
year = {2025},
date = {2025-03-22},
urldate = {2025-09-00},
journal = {Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy},
volume = {337},
publisher = {Elsevier BV},
abstract = {The halogenated C5-substituted uracil derivatives (5-fluor-, 5-chloro, and 5-bromouracil) have drawn attention recently due to their pharmacological uses, properties, and importance as biomarkers and water pollutants. From an analytical point of view, these species are expected to be at very low levels in biological and environmental samples, and the development of methodologies for their determination is a central goal in research. The Raman technique and one of its special effects, Surface-Enhanced Raman Scattering (SERS), is a very suitable approach for detecting and quantifying these compounds. In practice, enhancing Raman scattering requires a nanostructured noble metal surface with the species of interest attached to it. Still, to maximize the effect, a deeper comprehension of the nature of the analyte-metal surface interaction is desirable. The structural information SERS spectra provide can be complemented by theoretical approaches, such as the Density Functional Theory (DFT) calculations. This work studied three 5-halouracils attached to silver nanoparticles (AgNPs) from experimental and theoretical perspectives. The observed patterns in the spectroscopic behavior showed a trend related to the electronegativity at the halogenated moieties, suggesting their direct influence in enhancing Cdouble bondC and Cdouble bondO stretching modes. Then, the formation of base pairs with adenine through hydrogen bonding was studied as a strategy to improve the detectability through SERS, supported by the well-known high affinity of adenine towards metal nanoparticles. We show that adenine favors the orientation of the 5-halouracils, reaching an additional signal enhancement that is very useful for analytical purposes, as demonstrated for 5-FU, reaching a limit of detection (LOD) of 2.36 nmol L−1. Wavenumber shifts and intensification of Nsingle bondH modes observed in the SERS spectra, along with DFT calculations, strongly suggest that forming hydrogen bonding (Nsingle bondH----N) upon the interaction of the base pairs with an Ag20 cluster is key for improving the halouracils LOD through SERS.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
@workingpaper{fujisawa2025universalramanspectroscopicframework,
title = {A Universal Raman Spectroscopic Framework for Defect Quantification in Mono-to-Multilayer Graphenic Materials: The Graphene Atlas},
author = {Kazunori Fujisawa and Bruno R. Carvalho and Pedro Venezuela and Cheon-Soo Kang and Yoong Ahm Kim and Takuya Hayashi and Mauricio Terrones},
url = {https://arxiv.org/abs/2503.12459},
year = {2025},
date = {2025-03-16},
urldate = {2025-01-01},
abstract = {Point defects, though atomically small, significantly influence the properties of 2D materials. A general method for characterizing point defect density (nD) in graphenic materials with arbitrary layer number (nL) is currently lacking. Here, we introduce the Graphene Atlas, a non-destructive Raman spectroscopy-based framework for defect quantification in diverse graphenic systems. We demonstrate that the relative fractions of the double-resonance D and 2D Raman bands, which arise from competing scattering processes, exhibit a universal relationship with nD, independent of nL. Plotting Raman data on a plane defined by defect-related and layer number-related parameters enables a direct and quantitative determination of nD and nL. This Graphene Atlas provides a transformative tool for real-time defect quantification in scalable manufacturing of graphenic materials, bridging fundamental research and industrial applications. This framework establishes a new standard for defect characterization of graphenic systems, facilitating their optimization for advanced technological applications. },
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@workingpaper{luna2025machinelearninginteratomicpotentialtwisted,
title = {Machine-Learning Interatomic Potential for Twisted Hexagonal Boron Nitride: Accurate Structural Relaxation and Emergent Polarization},
author = {Wilson Nieto Luna and Robin Smeyers and Cem Sevik and Lucian Covaci and Milorad V. Milošević},
url = {https://arxiv.org/abs/2503.11797},
year = {2025},
date = {2025-03-14},
urldate = {2025-01-01},
abstract = {The emerging ferroelectric properties of two-dimensional (2D) heterostructures are at the forefront of science and prospective technology. In moiré bilayers, twisting or heterostructuring causes local atomic reconstruction, which even at picometer scale, can lead to pronounced ferroelectric polarization. Accurately determining this reconstruction utilizing ab initio methods is unfeasible for the relevant system sizes, but modern machine-learning interatomic potentials offer a viable solution. Here, we present the Gaussian Approximation Potential for twisted hexagonal boron nitride (hBN) layers validated against ab initio datasets. This approach enables the precise analysis of their structural properties, which is particularly relevant at small twist angles. We couple the structural information to a tight-binding model based on accurate interatomic positioning, and determine the twist-dependent polarization, yielding results that closely align with previous experimental findings - even at room temperature. This methodology enables further studies that are unattainable otherwise and is transferable to other 2D materials of interest. },
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@article{NarcisoPedrosa2025,
title = {Interlayer Excitons and Radiative Lifetimes in MoSe2/SeWS Bilayers: Implications for Light-Emitting Diodes},
author = {Renan Narciso Pedrosa and Cesar E. P. Villegas and Alexandre Reily Rocha and Rodrigo G. Amorim and Wanderlã L. Scopel},
url = {https://pubs.acs.org/doi/full/10.1021/acsanm.4c06994},
doi = {10.1021/acsanm.4c06994},
issn = {2574-0970},
year = {2025},
date = {2025-03-14},
urldate = {2025-03-14},
journal = {ACS Appl. Nano Mater.},
volume = {8},
number = {10},
pages = {5051--5058},
publisher = {American Chemical Society (ACS)},
abstract = {Interlayer excitons, formed by electrical charge transfer between layers of 2D van der Waals heterostructures, are of the utmost importance for light-detection and light-harvesting applications. In particular, Janus-based heterostructures are promising platforms to observe robust interlayer exciton dynamics due to their intrinsic electric field. Here, we carry out ground- and excited-state first-principles calculations, based on the G0W0 approach and the solution of the Bethe–Salpeter equation, to investigate the energetic, electronic, and excitonic properties of MoSe2/WSSe van der Waals heterobilayers. Our results show that the heterojunction presents features of type-II band alignment and tightly bound, long-lived interlayer excitons. Indeed, the lowest dipole-allowed excitonic state possesses an interlayer character and a slight deviation of 12% in its binding energy compared to the lowest-energy intralayer exciton. Furthermore, the interlayer excitons have transition rates ∼55 times smaller than the intralayer ones, which translates into a longer radiative lifetime of dozens of nanoseconds at room temperature. This is up to 2 orders of magnitude greater than that of the lowest-energy intralayer exciton. The findings emphasize the critical role of Janus-based heterojunctions in influencing interlayer exciton radiative lifetimes, indicating that the system possesses considerable potential for application in optoelectronic devices such as a light-emitting diode (LED) or photodetector.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
@workingpaper{dias2025catenarylikerippledbiphenylenegraphenelateral,
title = {Catenary-like rippled biphenylene/graphene lateral heterojunction},
author = {Victor M. S. C. Dias and Danilo P. Kuritza and Igor S. S. Oliveira and Jose E. Padilha and Roberto H. Miwa},
url = {https://arxiv.org/abs/2503.07816},
doi = { https://doi.org/10.48550/arXiv.2503.07816},
year = {2025},
date = {2025-03-10},
urldate = {2025-01-01},
abstract = {In this study, we conduct a first-principles analysis to explore the structural and electronic properties of curved biphenylene/graphene lateral junctions (BPN/G). We start our investigation focusing on the energetic stability of BPN/G by varying the width of the graphene region, BPN/Gn. The electronic structure of BPN/Gn reveals (i) the formation of metallic channels mostly localized along the BPN stripes, where (ii) the features of the energy bands near the Fermi level are ruled by the width (n) of the graphene regions, Gn. In the sequence, we find that the hydrogenation of BPN/Gn results in a semiconductor system with a catenary-like rippled geometry. The electronic states of the hydrogenated system are mainly confined in the curved Gn regions, and the dependence of the bandgap on the width of Gn is similar to that of hydrogenated armchair graphene nanoribbons. The effects of curvature on the electronic structure, analyzed in terms of external mechanical strain, revealed that the increase/decrease of the band gap is also dictated by the width of the Gn region. Further electronic transport calculations reveal a combination of strong transmission anisotropy and the emergence of negative differential resistance. Based on these findings, we believe that rippled biphenylene/graphene systems can be useful for the design of two-dimensional nanodevices. },
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@workingpaper{deoliveira2025formationmechanismstabilityrole,
title = {Formation mechanism, stability and role of zinc and sulfur vacancies on the electronic properties and optical response of ZnS},
author = {P. R. A Oliveira and L. Lima and G. Felix and Pedro Venezuela and F. Stavale},
url = {https://arxiv.org/abs/2502.15670},
year = {2025},
date = {2025-02-21},
urldate = {2025-01-01},
abstract = {Combining experimental and theoretical tools, we report that Zn vacanciesplay an important role in the electronic and optical responses of ZnS sphalerite. The defective surface of ZnS (001) single crystal prepared in ultra-highvacuum conditions, has been shown to exhibit a semiconducting character instead of the insulating properties of the pristine structure, as revealed by X-ray photoelectron spectroscopy (XPS). Interestingly, this effect is attributed to the formation of zinc vacancies in the ZnS system, which also alter the optical response of the material, as supported by photoluminescence (PL) measurements comparing pristine and S-rich (Zn-poor) ZnS. To address these findings from a theoretical point of view, first principles calculations based on density functional theory (DFT) were performed. The optical properties of cation-defective ZnS were evaluated using random-phase approximation and hybrid functional DFT calculations. These calculations revealed absorption peaks in the visible range in the defective ZnS rather than solely in the ultra-violet range obtained for defect-free ZnS. The combination of this finding with joint density of states (JDOS) analysis explains the emergence of new luminescence peaks observed in the PL spectra of cation-defective ZnS. These findings highlight the role of Zn vacancies in tuning ZnS optical properties, making it a potential candidate for optoelectronic applications such as LEDs and photodetectors.},
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@workingpaper{cysne2025orbitronicstwodimensionalmaterials,
title = {Orbitronics in Two-dimensional Materials},
author = {Tarik P. Cysne and Luis M. Canonico and Marcio Costa and R. B. Muniz and Tatiana G. Rappoport},
url = {https://arxiv.org/abs/2502.12339},
year = {2025},
date = {2025-02-17},
urldate = {2025-01-01},
abstract = {Orbitronics explores the control and manipulation of electronic orbital angular momentum in solid-state systems, opening new pathways for information processing and storage. One significant advantage of orbitronics over spintronics is that it does not rely on spin-orbit coupling, thereby broadening the range of non-magnetic materials that can be utilized for these applications. It also introduces new topological features related to electronic orbital angular momentum, and clarifies some long-standing challenges in understanding experiments that rely on the conventional concept of valley transport. This review highlights recent advances in orbitronics, particularly in relation to two-dimensional materials. We examine the fundamental principles underlying the generation, transport, and dynamics of orbital angular momentum to illustrate how the unique properties of two-dimensional materials can promote orbitronic phenomena. We also outline potential future research directions and address some outstanding questions in this field.},
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@workingpaper{cardias2025edgenoncollinearmagnetismnanoribbons,
title = {Edge non-collinear magnetism in nanoribbons of Fe3GeTe2 and Fe3GaTe2},
author = {R. Cardias and Anders Bergman and Hugo U. R. Strand and R. B. Muniz and Marcio Costa},
url = {https://arxiv.org/abs/2502.12356},
year = {2025},
date = {2025-02-17},
urldate = {2025-01-01},
abstract = {Fe3GeTe2 and Fe3GaTe2 are ferromagnetic conducting materials of van der Waals-type with unique magnetic properties that are highly promising for the development of new spintronic, orbitronic and magnonic devices. Even in the form of two-dimensional-like ultrathin films, they exhibit relatively high Curie temperature, magnetic anisotropy perpendicular to the atomic planes and multiple types of Hall effects. We explore nanoribbons made from single layers of these materials and show that they display non-collinear magnetic ordering at their edges. This magnetic inhomogeneity allows angular momentum currents to generate magnetic torques at the sample edges, regardless of their polarization direction, significantly enhancing the effectiveness of magnetization manipulation in these systems. We also demonstrate that it is possible to rapidly reverse the magnetization direction of these nanostructures by means of spin-orbit and spin-transfer torques with rather low current densities, making them quite propitious for non-volatile magnetic memory units.},
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@workingpaper{goswami2025exceptionallyhighnonlinearoptical,
title = {Exceptionally High Nonlinear Optical Response in Two-dimensional Type II Dirac Semimetal Nickel di-Telluride (NiTe2)},
author = {Saswata Goswami and Caique Campos Oliveira and Bruno Ipaves and Preeti Lata Mahapatra and Varinder Pal and Suman Sarkar and Pedro A. S. Autreto and Samit K. Ray and Chandra Sekhar Tiwary},
url = {https://arxiv.org/abs/2502.10781},
year = {2025},
date = {2025-02-15},
urldate = {2025-02-15},
abstract = {Nickel ditelluride (NiTe2) is a newly identified Type-II Dirac semimetal, showing novel characteristics in electronic transport and optical experiments. In this study, we explored the nonlinear optical properties of two-dimensional NiTe2 using experimental and computational techniques (density functional theory-based approach). Few layered two-dimensional NiTe2 (2D-NiTe2) are synthesized using liquid phase exfoliation (LPE), which is characterized using X-ray diffraction technique, transmission electron, and atomic force microscopy. The nonlinear refractive index and third-order nonlinear susceptibility of the prepared 2D-NiTe2 are determined from the self-induced diffraction pattern generated using different wavelengths ( 405, 532, and 650 nm) in the far field. In addition, the diffraction pattern generated by spatial self-phase modulation (SSPM) is further verified by varying concentration (2D-NiTe2 in the IPA solvent), wavelength (of incoming laser beams), and cuvette width (active path length). The high value of third-order nonlinear susceptibility (in order of 10-9 e.s.u.) determined using SSPM in the 2D-NiTe2 can be attributed to the laser-induced hole coherence effect. Lastly, utilizing the reverse saturable absorption property of 2D-hBN, asymmetric light propagation is also demonstrated in the 2D-NiTe2/2D-hBN heterostructure.},
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@workingpaper{ipaves2025enhancingcatalystactivitytwodimensional,
title = {Enhancing catalyst activity of two-dimensional C4N2 through doping for the hydrogen evolution reaction},
author = {Bruno Ipaves and João F. Justo and James M. de Almeida and Lucy V. C. Assali and Pedro A. S. Autreto},
url = {https://arxiv.org/abs/2502.10863},
year = {2025},
date = {2025-02-15},
urldate = {2025-01-01},
abstract = {This study investigates the structural, electronic, and catalytic properties of pristine and doped C4N2 nanosheets as potential electrocatalysts for the hydrogen evolution reaction. The pristine C36N18 nanosheets exhibit limited HER activity, primarily due to high positive Gibbs free energies (> 2.2 eV). To enhance catalytic performance, doping with B, Si, or P at the nitrogen site was explored. Among these systems, B-doped C36N17 nanosheets exhibit the most promising catalytic activity, with a Gibbs free energy close to zero (≈ -0.2 eV), indicating efficient hydrogen adsorption. Band structure, projected density of states, charge density, and Bader charge analyses reveal significant changes in the electronic environment due to doping. While stacking configurations (AA′A′′ and ABC) have minimal effect on catalytic performance, doping - particularly with B -substantially alters the electronic structure, optimizing hydrogen adsorption and facilitating efficient HER. These findings suggest that B-doped C36N17 nanosheets could serve as efficient cocatalysts when combined with metallic materials, offering a promising approach to enhance catalytic efficiency in electrocatalytic and photocatalytic applications.},
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@workingpaper{shafiei2025lightinduceddissipationlessstatesmagnetic,
title = {Light-induced dissipationless states in magnetic topological insulators with hexagonal warping},
author = {Mohammad Shafiei and Milorad V. Milošević},
url = {https://arxiv.org/abs/2502.10164},
year = {2025},
date = {2025-02-14},
urldate = {2025-01-01},
abstract = {Magnetic impurities in topological insulators (TIs) induce backscattering via magnetic torque, unlike pristine TIs where spin-orbit locking promotes dissipationless surface states. Here we reveal that one can suppress that unwanted backscattering and dissipation in magnetic TIs using high-frequency linearly polarized light (LPL). By carefully considering the hexagonal warping of the Fermi surface of the TI, we demonstrate how the coupling between Dirac surface states and LPL can effectively reduce backscattering on magnetic dopants, enhance carrier mobility and suppress resistance, even entirely. These findings open up avenues for designing ultra low-power sensing and spintronic technology.},
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@workingpaper{serquen2025crystallineenvironmentluminescenttb3,
title = {On the crystalline environment of luminescent Tb3+ ions embedded in indium tin oxide thin films: a DFT and Crystal field analysis assessment},
author = {E. Serquen and K. Lizárraga and L. A. Enrique and F. Bravo and S. Mishra and P. LLontop and Pedro Venezuela and L. R. Tessler and J. A. Guerra},
url = {https://arxiv.org/abs/2502.08517},
doi = { https://doi.org/10.48550/arXiv.2502.08517},
year = {2025},
date = {2025-02-12},
urldate = {2025-02-12},
abstract = {We assess the local symmetry and crystal environment of trivalent terbium ions embedded in an indium tin oxide (ITO) matrix with bixbyite structure. The mbox{Tb3+} ions tend to substitute mbox{In3+} ions in two different cationic sites (b and d). Density Functional Theory (DFT) calculations suggest that the mbox{Tb3+} ions are mainly located at C2 symmetry sites relaxing selection rules and enabling electric dipole transitions, with the $^5text{D}_4rightarrowleftindex^7{text{F}}_2$ transition being the most intense, providing a red color to the light emission. Photoluminescence emission spectra under UV excitation at qty{83}{kelvin} revealed 30 intra-4f transitions, which were assigned to the $leftindex^7{text{F}}_J$ ground multiplet of the mbox{Tb3+} ion. Crystal-field analysis shows a strong alignment between calculated and observed energy levels, yielding a standard deviation of $sigma=qty{15.1}{centipermetre}$. We believe these results can help to understand the activation mechanisms of mbox{Tb3+} luminescent centers in transparent conductive oxides, as well as the potential to modulate mbox{Tb3+} emission color through its crystalline environment.},
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@workingpaper{šabani2025orbitallyresolvedmagneticexchangecri3,
title = {Beyond the orbitally-resolved magnetic exchange in CrI3 and NiI2},
author = {Denis Šabani and Cihan Bacaksız and Milorad V. Milošević},
url = {https://arxiv.org/abs/2502.08273},
doi = { https://doi.org/10.48550/arXiv.2502.08273},
year = {2025},
date = {2025-02-12},
urldate = {2025-02-12},
abstract = {The pertinent need for microscopic understanding of magnetic exchange motivated us to go beyond the existing theories and develop a systematic method to quantify all possible mechanisms that contribute to magnetic exchange for an arbitrary pair of atoms in a given material. We apply it to the archetypal 2D magnetic monolayers CrI3 and NiI2, to reveal the previously underrated dx2-y2,dx2-y2 contribution as either the leading or the second largest contribution to the total magnetic exchange. We proceed to explore the microscopic mechanisms behind all the non-zero orbital contributions in both CrI3 and NiI2, and generalize the findings to other magnetic monolayers dominated by d8 and d3 electronic configurations of the magnetic atoms.},
keywords = {},
pubstate = {published},
tppubtype = {workingpaper}
}
@article{Orenstein2025,
title = {Complex thermoelectric transport in Bi-Sb alloys},
author = {Rachel Orenstein and Kamil Ciesielski and Karol Synoradzki and Jiaxing Qu and Ferdaushi Alam Bipasha and Lidia C. Gomes and Jesse M. Adamczyk and Shannon Berger and Elif Ertekin and Eric S. Toberer},
url = {https://pubs.aip.org/aip/apr/article-abstract/12/1/011409/3333905/Complex-thermoelectric-transport-in-Bi-Sb-alloys?redirectedFrom=fulltext},
doi = {10.1063/5.0237802},
issn = {1931-9401},
year = {2025},
date = {2025-02-05},
urldate = {2025-03-01},
volume = {12},
number = {1},
publisher = {AIP Publishing},
abstract = {Bi1−xSbx alloys are classic thermoelectric materials for near-cryogenic applications. Despite more than half a century of study, unraveling the underlying transport physics within this space has been nontrivial due to the complex electronic structure, disorder, and small bandgap within these alloys. Furthermore, as Peltier coolers, Bi1−xSbx alloys operate in a bipolar regime; as such, understanding the impact of minority carriers is critical for further improvements in device performance. This study unites first principles calculations with low-temperature experimental measurements to create a generalized model for transport within semiconducting Bi-Sb alloys. Our exploration reveals the interplay between the complex, degenerate valence band structure with the extremely light conduction bands. By building a hybrid computational/experimental model, an understanding of both the electron and hole relaxation times emerges both as a function of temperature and energy. Special quasi-random supercell calculations reveal that, despite significant atomic disorder, the electronic band structures within the alloy remains largely unaffected and electron–phonon scattering dominates. For charge carriers near the band edges, the relaxation times are thus extremely long, consistent with cyclotronic behavior appearing at low magnetic fields (≪ 1 T). Modeling thermoelectric performance suggests that the valence band edge deformation potential is significantly weaker and highlights the potential for p-type compositions to meet or exceed the current n-type alloys.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
@article{Rajeev2025,
title = {Enhanced Non‐Invasive Radio Frequency Heating Using 2D Pyrite (Pyritene)},
author = {Karthik Rajeev and Bruno Ipaves and Caique Campos de Oliveira and Sreeram Punathil Raman and Swastik Kar and Douglas S Galvao and Pedro A. S. Autreto and Chandra Sekhar Tiwary},
url = {https://onlinelibrary.wiley.com/doi/10.1002/smtd.202402066},
doi = {10.1002/smtd.202402066},
issn = {2366-9608},
year = {2025},
date = {2025-02-05},
urldate = {2025-02-05},
journal = {Small Methods},
publisher = {Wiley},
abstract = {Radiofrequency (RF) heating is a new, less invasive alternative to invasive heating methods that use nanoparticles for tumour therapy. But pinpoint local heating is still hard. Molecular interactions form a hybrid structure with unique electrical characteristics that enable RF heating in this work, which explores RF heating in a biological cell (yeast)‐2D FeS2 system. Substantial processes have been uncovered via experimental investigations and density functional theory (DFT) computations. At 3 W and 50 MHz, RF heating reaches 54°C in 40 s, which is enough to kill yeast cells, while current‐voltage measurements reveal ionic diode‐like properties. Interactions between yeast lipid molecules and 2D FeSk, as shown by density‐functional theory calculations, cause an imbalance in the distribution of charges and the creation of polar, conductive channels. Insights into biological heating applications based on radio frequency (RF) technology are offered by this work, which lays forth a framework for investigating 2D material‐biomolecule interactions.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}