Optical Detection of Single-Electron Tunneling into a Semiconductor Quantum Dot

Auger recombination is a non-radiative process, where the recombination energy of an electron-hole pair is transferred to a third charge carrier. It is a common effect in colloidal quantum dots that quenches the radiative emission with an Auger recombination time below nanoseconds. In self-assembled QDs, the Auger recombination has been observed with a much longer recombination time in the order of microseconds.Here, we use two-color laser excitation on the exciton and trion transition in resonance fluorescence on a single self-assembled quantum dot to monitor in real-time every quantum event of the Auger process. Full counting statistics on the random telegraph signal give access to the cumulants and demonstrate the tunability of the Fano factor from a 1 arXiv:1911.04789v2 [cond-mat.mes-hall] 13 Nov 2019Poissonian to a sub-Poissonian distribution by Auger-mediated electron emission from the dot. Therefore, the Auger process can be used to tune optically the charge carrier occupation of the dot by the incident laser intensity; independently from the electron tunneling from the reservoir by the gate voltage. Our findings are not only highly relevant for the understanding of the Auger process, it also demonstrates the perspective of the Auger effect for controlling precisely the charge state in a quantum system by optical means.The excitonic transitions in self-assembled quantum dots (QDs) 1,2 realize perfectly a twolevel system in a solid-state environment. These transitions can be used to generate single photon sources 3,4 with high photon indistinguishability, 5,6 an important prerequisite to use quantum dots as building blocks in (optical) quantum information and communication technologies. 7,8 Moreover, self-assembled QDs are still one of the best model systems to study in an artificial atom the carrier dynamics, 9,10 the spin-and angular-momentum properties 11,12 and charge carrier interactions. 13 One important effect of carrier interactions is the Auger process: An electron-hole pair recombines and instead of emitting a photon, the recombination energy is transferred to a third charge carrier, which is then energetically ejected from the QD. 14-17 This is a common effect, mostly studied in colloidal QDs, where it quenches the radiative emission with recombination times in the order of picoseconds to nanoseconds. [18][19][20] This limits the efficiency of optical devices containing QDs like LEDs 21,22 or single photon sources. [23][24][25] In self-assembled QDs, Auger recombination was speculated to be absent, and only recently, it was directly observed in optical measurements on a single self-assembled QD coupled to a charge reservoir with recombination times in the order of microseconds. 26As a single Auger process is a quantum event, it is unpredictable and only the statistical evaluation of many processes gives access to the physical information of the recombination

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“…As the same measurement technique is used, this methods section follows the Supplemental information of Kurzmann et al 29 Optical measurements…”

Section: Methodsmentioning

confidence: 99%

“…1b), sufficiently-high for recording single quantum events in a real-time measurement. 29 While the intensity of the exciton detection laser 2 is kept constant, the laser intensity of the trion excitation laser 1 is increased from 1.6 · 10 −7 µW/µm 2 up to 1.6 · 10 −5 µW/µm 2 .…”

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confidence: 99%

Real-Time Detection of Single Auger Recombination Events in a Self-Assembled Quantum Dot

et al. 2020

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“…The single-electron detection has also been used to measure electron-electron interference in the QD system [14], as well as the full counting statistics of superconducting junctions [15]. Furthermore, full counting statistics and spin dynamics in a quantum dot have been investigated using resonance fluorescence [16]. Usually, most experiments have been carried out at ultralow temperatures in the milliKelvin range; however, recently, single-electron detection has begun to be operated at room temperature by the optical blinking of a nearby semiconductor nanocrystal [17].…”

Section: Introductionmentioning

confidence: 99%

Photon Counting Statistics of a Microwave Cavity Coupled with Double Quantum Dots

et al. 2019

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The statistical properties of photon emission counting, especially the waiting time distributions (WTDs) and large deviation statistics, of a cavity coupled with the system of double quantum dots (DQDs) driven by an external microwave field were investigated with the particle-number-resolved master equation. The results show that the decay rate of the WTDs of the cavity for short and long time limits can be effectively tuned by the driving external field Rabi frequency, the frequency of the cavity photon, and the detuning between the microwave driving frequency and the energy-splitting of the DQDs. The photon emission energy current will flow from the thermal reservoir to the system of the DQDs when the average photon number of the cavity in a steady state is larger than that of the thermal reservoir; otherwise, the photon emission energy current will flow in the opposite direction. This also demonstrates that the effect of the DQDs can be replaced a thermal reservoir when the rate difference of a photon absorbed and emitted by DQDs is larger than zero; otherwise, it is irreplaceable. The results deepen our understanding of the statistical properties of photon emission counting. It has a promising application in the construction of nanostructured devices of photon emission on demand and of optoelectronic devices.

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“…Одноэлектроника является перспективным направлением микро-и наноэлектроники [1,2]. При этом основное исследуемое явление -одноэлектронный транспорт, представляющий собой последовательный поэлектронный туннельный перескок через квантоворазмерную структуру, например квантовую точку (КТ), либо пролет электрона в ней с некоторой временной задержкой.…”

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“…Практически основные исследования одноэлектронного транспорта в полупроводниках проводятся на квантово-размерных структурах кремния как основного материала микроэлектроники [2,3]. Кремний, однако, для рассматриваемых здесь явлений не может иметь предпочтений из-за экстремальной малости значения порядка 1 nm.…”

unclassified

Одноэлектронный Транспорт В Коллоидных Квантовых Точках Узкозонных Полупроводников

Жуков¹,

Гавриков²,

Крыльский³

2020

Письма В Журнал Технической Физики

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Single-electron transport in the planar structure of colloidal quantum dots of InSb, PbS, CdSe semiconductors was studied using a scanning tunneling microscope. On the current – voltage characteristics, sections of the current dip were observed similar to the Coulomb gap. Qualitative and numerical comparative estimates suggest that one-electron transport and a phenomenon similar to the Coulomb blockade are observed in the structure of the set of quantum dots. When measuring the current-voltage characteristics, the white-light illumination of the sample breaks the Coulomb blockade, and it can be expected that an instrument element based on such a structure will respond to individual photons. In the region of the Coulomb gap, current oscillations with frequencies in the terahertz range are possible.

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Optical Detection of Single-Electron Tunneling into a Semiconductor Quantum Dot

Cited by 59 publications

References 43 publications

Real-Time Detection of Single Auger Recombination Events in a Self-Assembled Quantum Dot

Real-Time Detection of Single Auger Recombination Events in a Self-Assembled Quantum Dot

Photon Counting Statistics of a Microwave Cavity Coupled with Double Quantum Dots

Одноэлектронный Транспорт В Коллоидных Квантовых Точках Узкозонных Полупроводников

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