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Electron spin coherence in semiconductors: Considerations for a spin-based solid state quantum computer architecture

Rogerio de Sousa·S. Das Sarma
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Abstract

We theoretically consider coherence times for spins in two quantum computer architectures, where the qubit is the spin of an electron bound to a P donor impurity in Si or within a GaAs quantum dot. We show that low temperature decoherence is dominated by spin-spin interactions, through spectral diffusion and dipolar flip-flop mechanisms. These contributions lead to 1-100 $μ$s calculated spin coherence times for a wide range of parameters, much higher than former estimates based on $T_{2}^{*}$ measurements.

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Rogerio de Sousa, S. Das Sarma. 2003-02-10. Electron spin coherence in semiconductors: Considerations for a spin-based solid state quantum computer architecture. https://doi.org/10.1103/physrevb.67.033301

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