Free energy of superconducting islands with even land odd numbers of electrons
Mineev V. P.
The difference between the thermodynamic potentials with odd and even numbers of electrons is calculated for unusual superconductors which have zeros in the spectrum of elementary excitations. The current through a superconducting electrometer with a Coulomb blockade made from such a superconductor is independent of the parity of the number of electrons in the electrometer. There can be a dependence of this sort only if the spectrum of the superconducting material is free of zeros. © 1994 American Institute of Physics.