Reversible nature of the orbital mechanism for the suppression of superconductivity

The properties of type II Q 1D organic superconductors are investigated theoretically, with a focus on the effect of magnetic-field twisting of the electron orbits. It is shown that the orbital effect is insufficient to keep Hc2 finite at T = 0, and that the critical temperature increases as the magnetic field is increased beyond the pseudocritical level. This result is considered consistent with the experimental observations of Jerome (1982) and probably applicable (with some restrictions) to the case of a layered superconductor in a magnetic field parallel to the layers.