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Electric-field control of a hydrogenic donors spin in a semiconductor

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 Added by Amrit De
 Publication date 2008
  fields Physics
and research's language is English




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An AC electric field applied to a donor-bound electron in a semiconductor modulates the orbital character of its wave function, which affects the electrons spin dynamics via the spin-orbit interaction. Numerical calculations of the spin dynamics of a hydrogenic donor (Si) embedded in GaAs, using a real-space multi-band k.p formalism, show the high symmetry of the hydrogenic donor state results in strongly nonlinear dependences of the electronic g tensor on applied fields. A nontrivial consequence is that the most rapid Rabi oscillations occur for electric fields modulated at a subharmonic of the Larmor frequency.



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