Nuclear spin switch in semiconductor quantum dots.
Nuclear spin switch in semiconductor quantum dots.
复制标题
半导体量子点中的核自旋开关。
DOI：
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发表时间：
2006
影响因子：
8.6
通讯作者：
M. Hopkinson
中科院分区：
文献类型：
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作者：
A. Tartakovskii;T. Wright;A. Russell;V. Fal’ko;A. B. Van'kov;J. Skiba;I. Drouzas;R. Kolodka;M. S. Skolnick;P. Fry;A. Tahraoui;Huiyun Liu;M. Hopkinson
结果表明，用圆偏振光照射InGaAs/GaAs自组装量子点，构成量子点的原子核可以被驱动到双稳区，在这种双稳区中，通过改变泵浦强度，可以产生阈值状的增强或局域核场的减小，最高可达3T。发现这种核自旋“开关”的激发功率阈值取决于外加磁场和电场。这一开关是由于核自旋极化对电子到点核的自旋转移动力学的强烈反馈而产生的。
We show that by illuminating an InGaAs/GaAs self-assembled quantum dot with circularly polarized light, the nuclei of atoms constituting the dot can be driven into a bistable regime, in which either a thresholdlike enhancement or reduction of the local nuclear field by up to 3 T can be generated by varying the pumping intensity. The excitation power threshold for such a nuclear spin "switch" is found to depend on both the external magnetic and electric fields. The switch is shown to arise from the strong feedback of the nuclear spin polarization on the dynamics of the spin transfer from electrons to the nuclei of the dot.