Theory of magnetotunneling spectroscopy in spin triplet p-wave superconductors

TL;DR

This paper investigates how magnetic fields affect zero-bias conductance peaks in p-wave superconductors, revealing unique behaviors that can help identify pairing symmetries through magnetotunneling spectroscopy.

Contribution

It demonstrates that ZBCP behavior under magnetic fields differs between p-wave and d-wave superconductors, and introduces magnetotunneling as a tool for pairing symmetry determination.

Findings

ZBCP in p-wave does not split under magnetic field.

ZBCP height in p_{x}+i p_{y} is sensitive to magnetic field.

Magnetotunneling can distinguish pairing symmetries in unconventional superconductors.

Abstract

We study the influence of a magnetic field $H$ on the zero-bias conductance peak (ZBCP) due to zero-energy Andreev bound state (ZES) in normal metal / unconventional superconductor. For p-wave junctions, ZBCP does not split into two by $H$ even for sufficiently low transparent junctions, where ZBCP clearly splits for d-wave. This unique property originates from the fact that for p-wave superconductors, perpendicularly injected quasiparticle form ZES, which contribute most dominantly on the tunneling conductance. In addition, we show that for $p_{x}$+i$p_{y}$-wave superconductor junctions, the height of ZBCP is sensitive to $H$ due to the formation of broken time reversal symmetry state. We propose that tunneling spectroscopy in the presence of magnetic field, $i.e.$, $magnetotunneling$, is an promising method to determine the pairing symmetry of unconventional superconductors.