We observe an experimental signature of the role of the phonons in spin relaxation between triplet and singlet states in a two-electron quantum dot. Using both the external magnetic field and the electrostatic confinement potential, we change the singlet-triplet energy splitting from 1.3 meV to zero and observe that the spin relaxation time depends non-monotonously on the energy splitting. A simple theoretical model is derived to capture the underlying physical mechanism. The present experiment confirms that spin-flip energy is dissipated in the phonon bath.
@article{arxiv.cond-mat/0609726,
title = {Experimental signature of phonon-mediated spin relaxation},
author = {T. Meunier and I. T. Vink and L. H. Willems van Beveren and K-J. Tielrooij and R. Hanson and F. H. L. Koppens and H. P. Tranitz and W. Wegscheider and L. P. Kouwenhoven and L. M. K. Vandersypen},
journal= {arXiv preprint arXiv:cond-mat/0609726},
year = {2009}
}