title: Pulsed nuclear pumping and spin diffusion in a single charged quantum dot.
abstract: 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.
authors.affiliation: E. L. Ginzton Laboratory, Stanford University, Stanford, California 94305, USA. tdladd@gmail.com
authors.forename: Thaddeus D
authors.initials: TD
authors.lastname: Ladd
authors.forename: David
authors.initials: D
authors.lastname: Press
authors.forename: Kristiaan
authors.initials: K
authors.lastname: De Greve
authors.forename: Peter L
authors.initials: PL
authors.lastname: McMahon
authors.forename: Benedikt
authors.initials: B
authors.lastname: Friess
authors.forename: Christian
authors.initials: C
authors.lastname: Schneider
authors.forename: Martin
authors.initials: M
authors.lastname: Kamp
authors.forename: Sven
authors.initials: S
authors.lastname: Höfling
authors.forename: Alfred
authors.initials: A
authors.lastname: Forchel
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Yamamoto