Journal of Physics Condensed Matter

Quantum phase transitions and phase diagram for a one-dimensional p-wave superconductor with an incommensurate potential

Xiaoming Cai

Published Mar 27, 2014• 5 citations

Abstract

The effect of the incommensurate potential is studied for the one-dimensional p-wave superconductor. It is determined by analyzing various properties, such as the superconducting gap, the long-range order of the correlation function, the inverse participation ratio and the Z2 topological invariant, etc. In particular, two important aspects of the effect are investigated: (1) as disorder, the incommensurate potential destroys the superconductivity and drives the system into the Anderson localized phase; (2) as a quasi-periodic potential, the incommensurate potential causes band splitting and turns the system with certain chemical potential into the band insulator phase. A full phase diagram is also presented in the chemical potential-incommensurate potential strength plane.

DOI: 10.1088/0953-8984/26/15/155701

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