High T-c superconductivity in a superlattice of quantum stripes

The superconducting gap for 2D electron gas in a superlattice of quantum stripes with a finite 1D periodic potential barrier is calculated. The resonant enhancement of the superconducting gap is found when the Fermi level is tuned near the bottom of the nth superlattice subband with n greater than or equal to 2. The critical charge density rho(c) for maximum T-c at the n = 2 resonance is mainly determined by the stripe width L and vice versa, while it is nearly independent on the amplitude of the potential barrier. The width of the resonance is determined by the interaction cutoff (h) over bar omega(0) and its shape by the ratio Delta E(n perpendicular to)/(h) over bar omega(0), where Delta E(n perpendicular to) is the transversal energy dispersion of the n subband due to the transverse hopping between stripes. (C) 1997 Elsevier Science Ltd.