Hidden Crossover Phenomena in Strongly Pauli Limited Multiband Superconductors ---Application to CeCu${}_2$Si${}_2$

Abstract

Motivated by recent experiments on heavy fermion materials CeCu${}_2$Si${}_2$ and UBe${}_{13}$, we develop a framework to capture generic properties of multiband superconductors with strong Pauli paramagnetic effect (PPE). In contrast to the single band case, the upper critical field $H_{c2}$ can remain second order transition even for strong PPE cases. The expected first order transition is hidden inside $H_{c2}$ and becomes a crossover due to the interplay of multibandness. The present theory based on full self-consistent solutions of the microscopic Eilenberger theory explains several mysterious anomalies associated with the crossover and the "empty" vortex core state which is observed by recent STM experiment on CeCu${}_2$Si${}_2$.

arXiv comment5 pages, 4 figures + 3 pages, 1 figure (supplementary material), published version

References in corpus (14)

• Superconducting phases of f-electron compounds
• Fulde-Ferrell-Larkin-Ovchinnikov State in Heavy Fermion Superconductors
• Field-induced superconducting phase of FeSe in the BCS-BEC cross-over
• Imaging Cooper Pairing of Heavy Fermions in CeCoIn5
• Multiband superconductivity with unexpected deficiency of nodal quasiparticles in CeCu2Si2
• Vortex states in superconductors with strong Pauli-paramagnetic effect
• Field dependence of the zero energy density of states around vortices in an anisotropic gap superconductor
• Pauli-Limited Multiband Superconductivity in KFe2As2
• Local density of states in the vortex lattice in a type II superconductor
• Effects of gap anisotropy upon the electronic structure around a superconducting vortex
• Electronic state around vortex in a two-band superconductor
• Field-Orientation Dependence of Low-Energy Quasiparticle Excitations in the Heavy-Electron Superconductor UBe13
• Thermodynamic Study of Nodal Structure and Multiband Superconductivity of KFe2As2
• Fulde-Ferrell-Larkin-Ovchinnikov States in Two-Band Superconductors

Cited by in corpus (8)

• Highly Anisotropic Superconducting Gap in Nematically Ordered and Tetragonal Phases of FeSe${}_{1-x}$S${}_x$
• Fully gapped $d$-wave superconductivity in CeCu${}_2$Si${}_2$
• Superconducting gap and vortex lattice of the heavy fermion compound CeCu_2Si_2
• Gap structure of FeSe determined by field-angle-resolved specific heat measurements
• Thermodynamic study of gap structure and pair-breaking effect by magnetic field in the heavy-fermion superconductor CeCu2Si2
• Interplay between effective mass anisotropy and Pauli paramagnetic effects in a multiband superconductor--Application to Sr2RuO4--
• Microscopic Eilenberger theory of Fulde-Ferrell-Larkin-Ovchinnikov states in the presence of vortices
• Connection between in-plane upper critical field $H_{c2}$ and gap symmetry in layered $d$-wave superconductors revisited