Tomography of pairing symmetry from magnetotunneling spectroscopy -- a case study for quasi-1D organic superconductors

TL;DR

This paper demonstrates how magnetotunneling spectroscopy can distinguish different anisotropic pairing symmetries in quasi-one-dimensional organic superconductors by analyzing the effects of magnetic fields on the tunneling spectra.

Contribution

It introduces a method to identify pairing symmetry in organic superconductors using magnetic field effects on tunneling spectra, considering Fermi surface shape influences.

Findings

Magnetic fields reveal pairing symmetry via Doppler shift effects.

Fermi surface shape affects tunneling spectra features.

Method applicable to quasi-1D organic superconductors.

Abstract

We propose that anisotropic $p$-, $d$-, or $f$-wave pairing symmetries can be distinguished from a tunneling spectroscopy in the presence of magnetic fields, which is exemplified here for a model organic superconductor ${(TMTSF)}_{2}X$. The shape of the Fermi surface (quasi-one-dimensional in this example) affects sensitively the pairing symmetry, which in turn affects the shape (U or V) of the gap along with the presence/absence of the zero-bias peak in the tunneling in a subtle manner. Yet, an application of a magnetic field enables us to identify the symmetry, which is interpreted as an effect of the Doppler shift in Andreev bound states.