All-electrical measurement of the triplet-singlet spin relaxation time in self-assembled quantum dots

作者：Eltrudis K^*; Al Ashouri A; Beckel A; Ludwig A; Wieck A D; Geller M; Lorke A

来源：Applied Physics Letters, 2017, 111(9): 092103.

DOI：10.1063/1.4985572

We have measured the spin relaxation time of an excited two-electron spin-triplet state into its singlet ground state in self-assembled InAs/GaAs quantum dots. We use a time-resolved measurement scheme that combines transconductance spectroscopy with spin-to-charge conversion to address the vertical bar s up arrow, p up arrow > triplet state, where one electron is in the quantum dot s-shell and a second one in the p-shell. The evaluation of the state-selective tunneling times from the dots into a nearby two-dimensional electron gas allows us to determine the s-and p-shell occupation and extract the relaxation time from a rate equation model. A comparably long triplet-to-singlet spin relaxation time of 25 mu s is found. Published by AIP Publishing.

• 出版日期2017-8-28