Quantum size effects in thermodynamic superconducting properties of ultra thin films

Abstract

By using multi-bands BCS theory, we have calculated the superconductivity energy gap and the critical temperature of a thin-film metallic superconductor. The thermodynamic superconducting characteristics such as critical magnetic field, specific heat, as well as the tunneling conductance are investigated for varying film thickness and temperature. We find the oscillation of thermodynamic superconducting properties with the film thickness, including the thermodynamic critical field $H_c$, the specific heat of normal, superconducting state, and position of the differential tunneling conductance peak. The two universal constants the nth sub-band energy gap ${\Delta }_n$ at temperature $T=0K$ over $k_B{T}_c$, and the specific heat jump at $T_c$ over normal state specific heat at $T_c$ are independent of the film thickness. Their values are the same as in the bulk superconductor.

arXiv comment4 pages, 4 figures

References in corpus (4)

• Quantum size effects on the perpendicular upper critical field in ultra-thin lead films
• Oscillatory Electron-Phonon Coupling in Ultra-Thin Silver Films on V(100)
• Role of confined phonons in thin film superconductivity
• Charge-carrier transport properties of ultrathin Pb films

Cited by in corpus (5)

• Atypical BCS-BEC crossover induced by quantum-size effects
• Rise and fall of shape resonances in thin films of BCS superconductors
• Bound States in the Continuum in Two-Dimensional Serial Structures
• Shape resonances and shell effects in thin-film multiband superconductors
• Size effects in superconducting thin films coupled to a substrate