Thermal fluctuations and vortex melting in the classical superconductor Nb3Sn from high-resolution specific-heat measurements

Abstract

The range of critical thermal fluctuations in classical bulk superconductors is extremely small and especially in low fields hardly experimentally inaccessible. With a new type of calorimeter we have been able to resolve a small lambda anomaly within a narrow temperature range around the Hc2 line. We show that the evolution of the anomaly as a function of magnetic field follows scaling laws expected in the presence of critical fluctuations. The lower onset of the fluctuation regime shows many characteristics of a continuous solid-to-liquid transition in the vortex matter. It can be driven into a first-order vortex melting transition by a small AC field which helps the vortex matter to reach equilibrium.

arXiv comment12 pages, 5 figures new extended version, more figures added, more detailed discussion about the vortex melting transition

References in corpus (17)

• Elastic theory of flux lattices in presence of weak disorder
• Inverse melting of the vortex lattice
• Anomalous Peak Effect in CeRu2 and NbSe2 : Fracturing of a Flux Line Lattice?
• Extreme Type-II Superconductors in a Magnetic Field: A Theory of Critical Fluctuations
• Specific heat of Nb_3Sn: The case for a second energy gap
• Phase fluctuations and the pseudogap in YBa2Cu3Ox
• Theory of the vortex matter transformations in high Tc superconductor YBCO
• Thermal fluctuations correction to magnetization and specific heat of vortex solids in type II superconductors
• Peak effect in CeRu${}_2$:history dependence and supercooling
• Phase transition between the Bragg Glass and a disordered Phase in Nb3Sn, detected by 3rd harmonics of the AC magnetic susceptibility
• Exploring metastability via the third harmonic measurements in single crystals of $2H$-$NbS{e}_2$ showing anomalous Peak effect
• 3D Lowest Landau Level Theory Applied to YBCO Magnetization and Specific Heat Data: Implications for the Critical Behavior in the H-T Plane
• Magnetic-field-induced finite-size effect in the high-temperature superconductor YBa2Cu3O7-a comparison to rotating superfluid 4 He
• Supercooled vortex liquid and quantitative theory of melting of the flux line lattice in type II superconductors
• Precision calculation of magnetization and specific heat of vortex liquids and solids in type II superconductors
• First order melting of vortex lattice in strongly type-II three dimensional superconductors
• Renormalization-group theory for rotating 4He near the superfluid transition

Cited by in corpus (18)

• The Ginzburg-Landau Theory of Type II superconductors in magnetic field
• 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
• Neutron Stars in the Laboratory
• Thermodynamic origin of the peak effect in the superconductor Nb3Sn
• Real-space vortex glass imaging and the vortex phase diagram of SnMo6S8
• Melting of vortex lattice in magnetic superconductor $\mathrm{Rb}\mathrm{Eu}{\mathrm{Fe}}_4{\mathrm{As}}_4$
• Disorder-induced two-step melting of vortex matter in Co-intercalated NbSe${}_2$ single crystals
• Vortex phase dynamics in yttrium superhydride YH${}_6$ at megabar pressures
• Thermodynamic Observation of a Vortex Melting Transition in the Fe-based Superconductor Ba0.5K0.5Fe2As2
• Vortex-lattice melting and paramagnetic depairing in the nematic superconductor FeSe
• The Absence of Vortex Lattice Melting in a Conventional Superconductor
• Magnetocaloric Studies of the Peak Effect in Nb
• Application of a small oscillating magnetic field to reveal the peak effect in the resistivity of Nb3Sn
• Doping dependence of the critical fluctuation regime in the Fe-based superconductor Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• Magnetic field induced enlargement of the regime of critical fluctuations in the classical superconductor V3Si from high-resolution specific heat experiments
• Magnetic field induced 3D to 1D crossover in type II superconductors
• Estimates for the thermodynamic signatures of vortex-lattice melting in conventional superconductors
• Differential-thermal analysis around and below the critical temperature Tc of various low-Tc superconductors: A comparative study