Spin Lifetime in Electron-Doped InP Quantum Dots

TL;DR

This study investigates the spin relaxation and dephasing times of electrons in InP quantum dots using luminescence pump-probe and Hanle measurements, revealing millisecond-scale decay and nanosecond dephasing times.

Contribution

It provides the first detailed measurement of spin relaxation and dephasing times in electron-doped InP quantum dots using optical techniques.

Findings

Spin orientation decays on a millisecond timescale.

Spin dephasing time is 1.7 ns due to nuclear spin fluctuations.

Optical methods effectively characterize spin dynamics in quantum dots.

Abstract

Spin relaxation of electrons doped in InP quantum dots was studied by means of luminescence pump-probe and Hanle measurements. Optical pumping makes spins of doped electrons to be oriented in parallel to the helicity of the circularly polarized excitation. The luminescence pump-probe showed the spin orientation of the doped electrons decay on a millisecond time-scale. Hanle measurement clarified the spin dephasing relaxation time of doped electrons is 1.7 ns which is explained by the frozen fluctuation of nuclear spins.