Spin relaxation in charged quantum dots measured by coherent optical phase modulation spectroscopy

Measurements of the electron spin relaxation rate (T1)(T1) in charged GaAs quantum dots are made using a new nonlinear optical phase-modulation spectroscopy technique. The measured results of T1T1 as a function of magnetic field and temperature are best explained in terms of the spin relaxation by the phonon-assisted Dresselhaus spin–orbit scattering. T1T1 approaches 34 μs at zero magnetic field at 4.5 K.