Meunier, T. and Vink, I. T and Beveren, L. H. Willems van and Tielrooij, K.-J. and Koppens, F. H. L. and Tranitz, Hans-Peter and Wegscheider, Werner and Kouwenhoven, Leo P. and Vandersypen, L. M. K.
Experimental Signature of Phonon-Mediated Spin Relaxation in a Two-Electron Quantum Dot.
Physical Review Letters 98 (12), p. 126601.
We observe an experimental signature of the role of 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 nonmonotonously 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.