Partially-ordered vortex lattices in the high-field, low-temperature mixed state of quasi two-dimensional organic superconductors

Abstract

We report the results of high-field, low-temperature MuSR measurements of the quasi two-dimensional organic superconductors \k{appa}-(ET)2Cu(NCS)2 and \k{appa}-(ET)2Cu[N(CN)2]Br. The MuSR lineshapes for these compounds indicate the existence of partially-ordered vortex lattice phases in the high magnetic field regime, up to 2.5 T for the former compound and 4 T for the latter compound. The observed sharp loss of order is found to be consistent with a vortex-lattice melting transition that is predicted by numerical simulations of weakly coupled layers of pancake vortices. It is argued that the robustness of the partially-ordered vortex lattice phases could be due to strong flux-line pinning by a dilute ensemble of defects.

arXiv comment5 pages, 3 figures

References in corpus (14)

• Two-Dimensional Vortex Lattice Melting
• Evidence for structural and electronic instabilities at intermediate temperatures in $\kappa$-(BEDT-TTF)${}_2$X for X=Cu[N(CN)${}_2$]Cl, Cu[N(CN)${}_2$]Br and Cu(NCS)${}_2$: Implications for the phase diagram of these quasi-2D organic superconductors
• Possible new vortex matter phases in BSCCO
• Low-Field Phase Diagram of Layered Superconductors: The Role of Electromagnetic Coupling
• Test for interlayer coherence in a quasi-two-dimensional superconductor
• Universal Phase Diagram for Vortex States of Layered Superconductors in Strong Magnetic Fields
• Mott metal-insulator transition induced by utilizing a glass-like structural ordering in low-dimensional molecular conductors
• Disorder Effect on the Vortex Pinning by the Cooling Process Control in the Organic Superconductor $\kappa$-(BEDT-TTF)${}_2$Cu[N(CN)${}_2$]Br
• Muons as Local Probes of Three-body Correlations in the Mixed State of Type-II Superconductors
• Correlations in Two-Dimensional Vortex Liquids
• A Simple Analytical Model of Vortex Lattice Melting in 2D Superconductors
• Superconductivity and fluctuating magnetism in quasi two-dimensional kappa-(BEDT-TTF)2Cu[N(CN)2]Br probed with implanted muons
• Damping of dHvA oscillations and vortex-lattice disorder in the peak-effect region of strong type-II superconductors
• Irreversible Magnetization Deep in the Vortex-Liquid State of a 2D Superconductor at High Magnetic Fields

Cited by in corpus (1)

• Self-consistent Bogoliubov de Gennes theory of the vortex lattice state in a two-dimensional strong type-II superconductor at high magnetic fields