Measurement of the Spin Relaxation Time of Single Electrons in a Silicon MOS-Based Quantum Dot

TL;DR

This paper measures the spin relaxation time T1 of single electrons in a silicon quantum dot, revealing its dependence on magnetic field and discussing potential relaxation mechanisms.

Contribution

It provides the first detailed measurement of T1 in a Si/SiO2 quantum dot using charge sensing and pump-probe techniques, highlighting magnetic field effects.

Findings

T1 varies significantly with magnetic field strength.

Charge sensing effectively detects single-electron spin states.

Possible relaxation mechanisms are analyzed.

Abstract

We report on measurements of the spin relaxation time T1 of individual electron spins in the few electron regime of a Si/SiO2-based quantum dot (QD). Energy-spectroscopy of the QD has been performed using a charge sensing technique. The spin relaxation times are subsequently measured in the time-domain by a pump-and-probe method. For the QD that contains an unpaired spin, likely only a single electron, we find that T1 depends strongly on the applied magnetic field. Possible mechanisms leading to the observed spin relaxation are discussed.