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arXiv · 1403.2093

Hole Spin Coherence in a Ge/Si Heterostructure Nanowire

A. P. Higginbotham·T. W. Larsen·J. Yao·H. Yan·C. M. Lieber·C. M. Marcus·F. Kuemmeth
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Abstract

Relaxation and dephasing of hole spins are measured in a gate-defined Ge/Si nanowire double quantum dot using a fast pulsed-gate method and dispersive readout. An inhomogeneous dephasing time $T_2^* \sim 0.18~\mathrm{μs}$ exceeds corresponding measurements in III-V semiconductors by more than an order of magnitude, as expected for predominately nuclear-spin-free materials. Dephasing is observed to be exponential in time, indicating the presence of a broadband noise source, rather than Gaussian, previously seen in systems with nuclear-spin-dominated dephasing.

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A. P. Higginbotham, T. W. Larsen, J. Yao, H. Yan, C. M. Lieber, C. M. Marcus, F. Kuemmeth. 2014-06-13. Hole Spin Coherence in a Ge/Si Heterostructure Nanowire. https://doi.org/10.1021/nl501242b

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