Orbital-Induced Crossover of the Fulde-Ferrell-Larkin-Ovchinnikov Phase into Abrikosov-like States

Abstract

The Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state can emerge in superconductors for which the orbital critical field exceeds the Pauli limit. Here, we present angular-resolved specific-heat data of the quasi-two-dimensional organic superconductor $\kappa$-(ET)${}_2$Cu(NCS)${}_2$, with a focus on high fields in the regime of the FFLO transition. For an increasing out-of-plane tilt of the applied magnetic field, which leads to an increase of orbital contributions, we found that the nature of the superconducting transition changes from second to first order and that a further transition appears within the high-field superconducting phase. However, the superconducting state above the Pauli limit is stable for field tilt of several degrees. Since any finite perpendicular component of the magnetic field necessarily leads to quantization of the orbital motion, the resulting vortex lattice states compete with the modulated order parameter of the FFLO state leading to complex high-field superconducting phases. By solving the linearized self-consistency equation within weak-coupling BCS theory, we show that our results are clear experimental evidence of an orbital-induced transformation of the FFLO order-parameter into Abrikosov-like states of higher Landau levels.

arXiv commentMain text: 6 Pages, 4 Figures Supplement: 11 Pages, 6 Figures

References in corpus (26)

• The Flux-Line Lattice in Superconductors
• Fulde-Ferrell-Larkin-Ovchinnikov State in Heavy Fermion Superconductors
• Specific heat in the superconducting and normal state (2-300 K, 0-16 Teslas), and magnetic susceptibility of the 38-K superconductor MgB2: evidence for a multicomponent gap
• Calorimetric Evidence for a Fulde-Ferrell-Larkin-Ovchinnikov Superconducting State in the Layered Organic Superconductor κ$-(BEDT-TTF)$_2$Cu(NCS)$_2$
• Evidence of Andreev bound states as a hallmark of the FFLO phase in $\kappa$-(BEDT-TTF)${}_2$Cu(NCS)${}_2$
• Evidence for an FFLO state with segmented vortices in the BCS-BEC-crossover superconductor FeSe
• Magnetic-Torque Evidence for the Fulde-Ferrell-Larkin-Ovchinnikov State for In-Plane Magnetic Fields in the Organic Superconductor k-(BEDT-TTF)2Cu(NCS)2
• Phase Diagram and Spectroscopy of FFLO states of two-dimensional d-wave superconductors
• Thermodynamic evidence for the Fulde-Ferrell-Larkin-Ovchinnikov state in the KFe2As2 superconductor
• High-resolution ac-calorimetry studies of the quasi-2D organic superconductor $\kappa$-(BEDT-TTF)${}_2$Cu(NCS)${}_2$
• Phase Fluctuations and Kosterlitz-Thouless Transition in Two-Dimensional Fulde-Ferrell-Larkin-Ovchinnikov Superconductors
• Microscopic study of the Fulde-Ferrell-Larkin-Ovchinnikov state in an all-organic superconductor
• An Experimental and Semi-Empirical Method to Determine the Pauli-Limiting Field in Quasi 2D Superconductors as applied to $\kappa$-(BEDT-TTF)${}_2$Cu(NCS)${}_2$: Strong Evidence of a FFLO State
• New superconducting phases in field-induced organic superconductor lambda-(BETS)2FeCl4
• Calorimetric Measurements of Magnetic-Field-Induced Inhomogeneous Superconductivity Above The Paramagnetic Limit
• Interplay of paramagnetic, orbital and impurity effects on the phase transition of a normal metal to superconducting state
• Evidence for the presence of the Fulde-Ferrell-Larkin-Ovchinnikov state in CeCu${}_2$Si${}_2$ revealed using ${}^{63}$Cu NMR
• Quantum melting of the quasi-two-dimensional vortex lattice in kappa-(ET)2Cu(NCS)2
• Low temperature vortex liquid states induced by quantum fluctuations in the quasi two dimensional organic superconductor kappa-(BEDT-TTF)_{2} Cu(NCS)_{2}
• Quasiparticle Nodal Plane in the Fulde-Ferrell-Larkin-Ovchinnikov State of FeSe
• Interplay of the spin density wave and a possible Fulde-Ferrell-Larkin-Ovchinnikov state in $\mathrm{CeCoI}{\mathrm{n}}_5$ in rotating magnetic field
• Critical magnetic field of ultrathin superconducting films and interfaces
• Orbital Effect for the Fulde-Ferrell-Larkin-Ovchinnikov Phase in a Quasi-Two-Dimensional Superconductor in a Parallel Magnetic Field
• Four-fold anisotropy of the parallel upper critical magnetic field in a pure layered d-wave superconductor at $T=0$
• Magnetic-field-induced 1st order transition to FFLO state at paramagnetic limit in 2D superconductors
• Dissipation in the superconducting state of kappa-(BEDT-TTF)2Cu(NCS)2

Cited by in corpus (4)

• Atacamite Cu${}_2$Cl(OH)${}_3$ in High Magnetic Fields: Quantum Criticality and Dimensional Reduction of a Sawtooth-Chain Compound
• Constructing the Fulde-Ferrell-Larkin-Ovchinnikov state in antiferromagnetic insulator CrOCl
• Detecting Topological Phase Transition in Superconductor-Semiconductor Hybrids by Electronic Raman Spectroscopy
• Collective modes in Fulde-Ferrell-Larkin-Ovchinnikov superconductors: The role of long-range Coulomb interaction and signatures in density response