Optical control of spin coherence in singly charged (In,Ga)As/GaAs quantum dots.
Electron spin coherence has been generated optically in n-type modulation doped (In,Ga)As/GaAs quantum dots (QDs) which contain on average a single electron per dot. The coherence arises from resonant excitation of the QDs by circularly polarized laser pulses, creating a coherent superposition of an electron and a trion. Time dependent Faraday rotation is used to probe the spin precession of the optically oriented electrons about a transverse magnetic field. The coherence generation can be controlled by pulse intensity, being most efficient for (2n+1)pi pulses.
Greilich
A
A
Experimentelle Physik II, Universität Dortmund, D-44221 Dortmund, Germany.
Oulton
R
R
Zhukov
E A
EA
Yugova
I A
IA
Yakovlev
D R
DR
Bayer
M
M
Shabaev
A
A
Efros
Al L
AL
Merkulov
I A
IA
Stavarache
V
V
Reuter
D
D
Wieck
A
A