Deterministic fabrication of circular Bragg gratings coupled to single quantum emitters via the combination of in-situ optical lithography and electron-beam lithography

Abstract

In the present work, we investigate the coupling of deterministically pre-selected In(Ga)As/GaAs quantum dots (QDs) to low Q circular Bragg grating cavities by employing a combination of state-of-the-art low-temperature in-situ optical lithography and electron-beam lithography. The spatial overlap between the cavity mode and quantum emitter is ensured through the accurate determination of the QD position via precise interferometric position readout. Simultaneously, the high precision of the electron-beam lithography is exploited for the cavity fabrication. In order to optimize the spectral overlap, prior to cavity fabrication, finite-difference time-domain simulations are performed to estimate the spectral position of the cavity mode. A Purcell factor of 2 together with an increased count rate is reported for a deterministically positioned cavity where the emission line is detuned by 3.9 nm with respect to the cavity mode. This non-negligible Purcell enhancement for large detunings and, thus, the large range where this can be achieved points towards the possibility of using the cavity for the simultaneous enhancement of spectrally distinct transitions from the same quantum emitter located spatially in the mode maximum. Furthermore, investigations on the bending of the cavity membrane and the effects on the cavity mode and QD emission are presented.

Planar Semiconductor Membranes with Brightness Enhanced Embedded Quantum Dots via Electron Beam Induced Deposition of 3D Nanostructures: Implications for Solid State Lighting

“…However, it should be noted that the obtained results can be readily extended to self-assembled, and randomly distributed, Stranski-Krastanov QDs, e.g. by employing the consolidated alignment marks fabrication approach 13 . All depositions have been carried out on a sample of InGaAs in GaAs pyramidal quantum dots, grown via Metal Organic Vapor Phase Epitaxy (MOVPE) using an Aixtron 200 reactor on a (111)B GaAs substrate, patterned with inverted tetrahedra using conventional lithography and wet etching in Br:MeOH.…”

Quantum Dot Single-Photon Emission Coupled into Single-Mode Fibers with 3D Printed Micro-Objectives

“…For these optimization measurements, high-precision low temperature deterministic lithography was used 43 marking the emitter for further room temperature fabrication. 35,44 Furthermore, a first characterization of the fiber in-coupling performances was carried out in a high stability cryostat where the position of the fiber with respect to the sample can be precisely controlled (see the showing the fabrication of the integrated fiber coupled single-photon source. The TIR lens is printed onto the QD-microlens (left), followed by 3D printing the on-chip fiber chuck and inserting the SMF with the focus lens printed to its end facet (middle).…”

Исследование оптических и структурных свойств трехмерных островков InGaP(As), сформированных методом замещения элементов пятой группы

“…В настоящее время большой интерес проявляется к созданию приборов для управления одиночными фотонами [1][2][3][4][5][6][7][8][9] и нейроморфных вычислений, использующих в качестве излучателей полупроводниковые гетероструктуры с пониженной размерностью [10][11][12]. Наилучшими кандидатами на роль активных областей для излучателей в таких системах являются квантовые точки (КТ).…”