Mesoscopic conductance effects in InMnAs structures

TL;DR

This paper investigates quantum conductance fluctuations in InMnAs magnetic semiconductor structures, revealing temperature-dependent behaviors and magnetic field effects, which enhance understanding of mesoscopic quantum phenomena in these materials.

Contribution

It presents the first measurements of time-dependent and magnetic field-dependent universal conductance fluctuations in InMnAs structures, highlighting their temperature and magnetic field dependence.

Findings

TDUCF and MFUCF increase as temperature decreases

TDUCF are suppressed at 4 K and below under magnetic fields

Magnetic field orientation does not affect TDUCF suppression

Abstract

Quantum corrections to the electrical conduction of magnetic semiconductors are comparatively unexplored. We report measurements of time-dependent universal conductance fluctuations (TDUCF) and magnetic field dependent universal conductance fluctuations (MFUCF) in micron-scale structures fabricated from two different In$_{1-x}$Mn$_{x}$As thin films. TDUCF and MFUCF increasing in magnitude with decreasing temperature are observed. At 4 K and below, TDUCF are suppressed at finite magnetic fields independent of field orientation.