Electrical control of spin relaxation in a quantum dot.
We demonstrate electrical control of the spin relaxation time T1 between Zeeman-split spin states of a single electron in a lateral quantum dot. We find that relaxation is mediated by the spin-orbit interaction, and by manipulating the orbital states of the dot using gate voltages we vary the relaxation rate W identical withT1(-1) by over an order of magnitude. The dependence of W on orbital confinement agrees with theoretical predictions, and from these data we extract the spin-orbit length. We also measure the dependence of W on the magnetic field and demonstrate that spin-orbit mediated coupling to phonons is the dominant relaxation mechanism down to 1 T, where T1 exceeds 1 s.
Amasha
S
S
Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA. samasha@mit.edu
Maclean
K
K
Radu
Iuliana P
IP
Zumbühl
D M
DM
Kastner
M A
MA
Hanson
M P
MP
Gossard
A C
AC