Pulsed nuclear pumping and spin diffusion in a single charged quantum dot.
We report the observation of a feedback process between the nuclear spins in a single charged quantum dot under coherently pulsed optical excitation and its trion transition. The optical pulse sequence intersperses resonant narrow-band pumping for spin initialization with off-resonant ultrafast pulses for coherent electron-spin rotation. A hysteretic sawtooth pattern in the free-induction decay of the single electron spin is observed; a mathematical model indicates a competition between optical nuclear pumping and nuclear spin-diffusion. This effect allows dynamic tuning of the electron Larmor frequency to a value determined by the pulse timing, potentially allowing more complex coherent control operations.
Ladd
Thaddeus D
TD
E. L. Ginzton Laboratory, Stanford University, Stanford, California 94305, USA. tdladd@gmail.com
Press
David
D
De Greve
Kristiaan
K
McMahon
Peter L
PL
Friess
Benedikt
B
Schneider
Christian
C
Kamp
Martin
M
Höfling
Sven
S
Forchel
Alfred
A
Yamamoto
Yoshihisa
Y