Institute of Quantum Electronics, ETH-Zürich, Zürich, Switzerland.
Phys Rev Lett. 2010 Dec 31;105(26):267202. doi: 10.1103/PhysRevLett.105.267202. Epub 2010 Dec 21.
We show that a quantum interference effect in optical absorption from two electronic spin states of a solid-state emitter can be used to prepare the surrounding environment of nuclear spins in well-defined states, thereby suppressing electronic spin dephasing. The coupled electron-nuclei system evolves into a coherent population trapping state by optical-excitation-induced nuclear-spin diffusion for a broad range of initial optical detunings. The spectroscopic signature of this evolution where the single-electron strongly modifies its environment is a drastic broadening of the dark resonance in optical absorption experiments. The large difference in electronic and nuclear time scales allows us to verify the preparation of nuclear spins in the desired state.
我们表明，通过固态发射器两个电子自旋态的光学吸收中的量子干涉效应，可以用来将核自旋的周围环境制备到确定的状态，从而抑制电子自旋退相干。通过光激发诱导的核自旋扩散，在很宽的初始光失谐范围内，耦合的电子-核系统演化成相干布居囚禁态。这种演化的光谱特征是单电子强烈改变其环境，导致光学吸收实验中的暗共振急剧展宽。电子和核时间尺度的巨大差异使我们能够验证所需核自旋状态的制备。
