Spin and reoccupation noise in a single quantum dot beyond the fluctuation-dissipation theorem

Abstract

We report on the nonequilibrium spin noise of a single InGaAs quantum dot charged by a single hole under strong driving by a linearly polarized probe light field. The spectral dependency of the spin noise power evidences a homogeneous broadening and negligible charge fluctuations in the environment of the unbiased quantum dot. Full analysis of the spin noise spectra beyond the fluctuation-dissipation theorem yields the heavy-hole spin dynamics as well as the trion spin dynamics. Moreover, the experiment reveals an additional much weaker noise contribution in the Kerr rotation noise spectra. This additional noise contribution has a maximum at the quantum dot resonance and shows a significantly longer correlation time. Magnetic-field-dependent measurements in combination with theoretical modeling prove that this additional noise contribution unveils a charge reoccupation noise which is intrinsic in naturally charged quantum dots. arXiv:1708.01245v2 [cond-mat.mes-hall]

Hole-capture competition between a single quantum dot and an ionized acceptor

“…Together with a reoccupation rate of γ c,d = 0.7 µs −1 the measured ON contribution related to direct QD recharging from the continuum is well reproduced by the theory in agreement with the result in Ref. 9. The narrow ON contribution related to the recharging channel via the outer state (ON-o in Fig.…”

“…2(b)shows that the noise power of both contributions exhibits a maximum at the trion resonance. Both observations together prove that ON-d and ON-o result from occupation noise 9,19.…”

“…In fact, even at this large detuning the spin relaxation of the dressed state is not dominated by the hole spin but mainly by the electronin-trion spin flips (see Ref. 9 and sec. IV).…”

Ядерная Спиновая Динамика И Флуктуации В Анизотропной Модели Большого Ящика

“…Спиновая динамика электронов в квантовых точках в малых магнитных полях, как было показано Меркуловым, Эфросом и Розеном, определяется в основном сверхтонким взаимодействием с большим количеством спинов ядер кристаллической решетки [7]. Это взаимодействие приводит к ряду ярких спиновых явлений таких как эффекты Ханле [8], восстановление поляризации [9], резонансное спиновое усиление [10], синхронизация мод спиновой прецессии [11], спиновая инерция [12,13], низкочастотные спиновые флуктуации [14,15], динамическая поляризация электронных спинов [16,17] и др.…”

Heralded Universal Quantum Gate and Entangler Assisted by Imperfect Double‐Sided Quantum‐Dot‐Microcavity Systems

“…proposed a QD‐cavity system, for example, an electron confined in a self‐assembled In(Ga)As QD or a GaAs interface QD inside an optical resonant microcavity. Although this device has not been realized yet in QD system, there are lots of experiments with respect to it . Subsequently, such equipment was employed as platform for implementing emission‐based parallel quantum computation, error‐rejecting quantum computation, hyper‐parallel quantum computation, hyper‐entanglement purification, hyper‐entanglement concentration, quantum repeater, hyperentangled Bell‐state analysis, single‐photon transistor, and so on.…”