Anomaly in the heat capacity of Kondo superconductors

Abstract

Using numerical renormalization group we study thermodynamic properties of a magnetic impurity described by the Anderson impurity model in a superconducting host material described by the BCS Hamiltonian. When the Kondo temperature in the normal state, T_K, is comparable to the critical temperature of the superconducting transition, T_c, the magnetic doublet state may become degenerate with the Kondo singlet state, leading to a ln3 peak in the temperature dependence of the impurity contribution to the entropy. This entropy increase translates into an anomalous feature in the heat capacity which might have already been experimentally observed.

4 pages, 3 figures

References in corpus (9)

• The numerical renormalization group method for quantum impurity systems
• Scanning tunneling spectroscopy of high-temperature superconductors
• Spectral properties of locally correlated electrons in a BCS superconductor
• Josephson current through a single Anderson impurity coupled to BCS leads
• Finite quantum dissipation: the challenge of obtaining specific heat
• Numerical Renormalization Group Approach to a Quantum Dot Coupled to Normal and Superconducting Leads
• Energy Gaps and Kohn Anomalies in Elemental Superconductors
• Kondo effect in asymmetric Josephson couplings through a quantum dot
• Kondo screening in unconventional superconductors: The role of anomalous propagators

Cited by in corpus (4)

• Specific heat anomalies of open quantum systems
• Thermodynamic anomalies in open quantum systems: Strong coupling effects in the isotropic XY model
• On the origin of power-laws in equilibrium
• Numerical renormalization group calculation of impurity internal energy and specific heat of quantum impurity models