2023
Bekaert, Jonas; Bringmans, Levie; Milošević, Milorad V.
Ginzburg–Landau surface energy of multiband superconductors: derivation and application to selected systems Journal Article
Em: J. Phys.: Condens. Matter, vol. 35, não 32, 2023, ISSN: 1361-648X.
@article{Bekaert2023,
title = {Ginzburg–Landau surface energy of multiband superconductors: derivation and application to selected systems},
author = {Jonas Bekaert and Levie Bringmans and Milorad V. Milošević},
doi = {10.1088/1361-648x/acd217},
issn = {1361-648X},
year = {2023},
date = {2023-08-16},
urldate = {2023-08-16},
journal = {J. Phys.: Condens. Matter},
volume = {35},
number = {32},
publisher = {IOP Publishing},
abstract = {Abstract
We determine the energy of an interface between a multiband superconducting and a normal half-space, in presence of an applied magnetic field, based on a multiband Ginzburg–Landau (GL) approach. We obtain that the multiband surface energy is fully determined by the critical temperature, electronic densities of states, and superconducting gap functions associated with the different band condensates. This furthermore yields an expression for the thermodynamic critical magnetic field, in presence of an arbitrary number of contributing bands. Subsequently, we investigate the sign of the surface energy as a function of material parameters, through numerical solution of the GL equations. Here, we consider two distinct cases: (i) standard multiband superconductors with attractive interactions, and (ii) a three-band superconductor with a chiral ground state with phase frustration, arising from repulsive interband interactions. Furthermore, we apply this approach to several prime examples of multiband superconductors, such as metallic hydrogen and MgB2, based on microscopic parameters obtained from first-principles calculations.},
keywords = {Condensed Matter Physics, General Materials Science},
pubstate = {published},
tppubtype = {article}
}
<jats:title>Abstract</jats:title>
<jats:p>We determine the energy of an interface between a multiband superconducting and a normal half-space, in presence of an applied magnetic field, based on a multiband Ginzburg–Landau (GL) approach. We obtain that the multiband surface energy is fully determined by the critical temperature, electronic densities of states, and superconducting gap functions associated with the different band condensates. This furthermore yields an expression for the thermodynamic critical magnetic field, in presence of an arbitrary number of contributing bands. Subsequently, we investigate the sign of the surface energy as a function of material parameters, through numerical solution of the GL equations. Here, we consider two distinct cases: (i) standard multiband superconductors with attractive interactions, and (ii) a three-band superconductor with a chiral ground state with phase frustration, arising from repulsive interband interactions. Furthermore, we apply this approach to several prime examples of multiband superconductors, such as metallic hydrogen and MgB<jats:sub>2</jats:sub>, based on microscopic parameters obtained from first-principles calculations.</jats:p>
Han, Shulun; Tang, Chi Sin; Li, Linyang; Liu, Yi; Liu, Huimin; Gou, Jian; Wu, Jing; Zhou, Difan; Yang, Ping; Diao, Caozheng; Ji, Jiacheng; Bao, Jinke; Zhang, Lingfeng; Zhao, Mingwen; Milošević, Milorad V.; Guo, Yanqun; Tian, Lijun; Breese, Mark B. H.; Cao, Guanghan; Cai, Chuanbing; Wee, Andrew T. S.; Yin, Xinmao
Orbital‐Hybridization‐Driven Charge Density Wave Transition in CsV3Sb5 Kagome Superconductor Journal Article
Em: Advanced Materials, vol. 35, não 8, 2023, ISSN: 1521-4095.
@article{Han2022,
title = {Orbital‐Hybridization‐Driven Charge Density Wave Transition in CsV_{3}Sb_{5} Kagome Superconductor},
author = {Shulun Han and Chi Sin Tang and Linyang Li and Yi Liu and Huimin Liu and Jian Gou and Jing Wu and Difan Zhou and Ping Yang and Caozheng Diao and Jiacheng Ji and Jinke Bao and Lingfeng Zhang and Mingwen Zhao and Milorad V. Milošević and Yanqun Guo and Lijun Tian and Mark B. H. Breese and Guanghan Cao and Chuanbing Cai and Andrew T. S. Wee and Xinmao Yin},
doi = {10.1002/adma.202209010},
issn = {1521-4095},
year = {2023},
date = {2023-02-00},
journal = {Advanced Materials},
volume = {35},
number = {8},
publisher = {Wiley},
abstract = {AbstractOwing to its inherent non‐trivial geometry, the unique structural motif of the recently discovered kagome topological superconductor AV3Sb5 (A = K, Rb, Cs) is an ideal host of diverse topologically non‐trivial phenomena, including giant anomalous Hall conductivity, topological charge order, charge density wave (CDW), and unconventional superconductivity. Despite possessing a normal‐state CDW order in the form of topological chiral charge order and diverse superconducting gaps structures, it remains unclear how fundamental atomic‐level properties and many‐body effects including Fermi surface nesting, electron–phonon coupling, and orbital hybridization contribute to these symmetry‐breaking phenomena. Here, the direct participation of the V3d–Sb5p orbital hybridization in mediating the CDW phase transition in CsV3Sb5 is reported. The combination of temperature‐dependent X‐ray absorption and first‐principles studies clearly indicates the inverse Star‐of‐David structure as the preferred reconstruction in the low‐temperature CDW phase. The results highlight the critical role that Sb orbitals play and establish orbital hybridization as the direct mediator of the CDW states and structural transition dynamics in kagome unconventional superconductors. This is a significant step toward the fundamental understanding and control of the emerging correlated phases from the kagome lattice through the orbital interactions and provides promising approaches to novel regimes in unconventional orders and topology.},
keywords = {General Materials Science, Mechanical Engineering, Mechanics of Materials},
pubstate = {published},
tppubtype = {article}
}
AbstractOwing to its inherent non‐trivial geometry, the unique structural motif of the recently discovered kagome topological superconductor AV3Sb5 (A = K, Rb, Cs) is an ideal host of diverse topologically non‐trivial phenomena, including giant anomalous Hall conductivity, topological charge order, charge density wave (CDW), and unconventional superconductivity. Despite possessing a normal‐state CDW order in the form of topological chiral charge order and diverse superconducting gaps structures, it remains unclear how fundamental atomic‐level properties and many‐body effects including Fermi surface nesting, electron–phonon coupling, and orbital hybridization contribute to these symmetry‐breaking phenomena. Here, the direct participation of the V3d–Sb5p orbital hybridization in mediating the CDW phase transition in CsV3Sb5 is reported. The combination of temperature‐dependent X‐ray absorption and first‐principles studies clearly indicates the inverse Star‐of‐David structure as the preferred reconstruction in the low‐temperature CDW phase. The results highlight the critical role that Sb orbitals play and establish orbital hybridization as the direct mediator of the CDW states and structural transition dynamics in kagome unconventional superconductors. This is a significant step toward the fundamental understanding and control of the emerging correlated phases from the kagome lattice through the orbital interactions and provides promising approaches to novel regimes in unconventional orders and topology.
