Hybrid Integration of Solid-State Quantum Emitters on a Silicon Photonic Chip

Abstract

Scalable quantum photonic systems require efficient single photon sources coupled to integrated photonic devices. Solid-state quantum emitters can generate single photons with high efficiency, while silicon photonic circuits can manipulate them in an integrated device structure. Combining these two material platforms could, therefore, significantly increase the complexity of integrated quantum photonic devices. Here, we demonstrate hybrid integration of solid-state quantum emitters to a silicon photonic device. We develop a pickand-place technique that can position epitaxially grown InAs/InP quantum dots emitting at telecom wavelengths on a silicon photonic chip deterministically with nanoscale precision.We employ an adiabatic tapering approach to transfer the emission from the quantum dots to the waveguide with high efficiency. We also incorporate an on-chip silicon-photonic beamsplitter to perform a Hanbury-Brown and Twiss measurement. Our approach could enable integration of pre-characterized III-V quantum photonic devices into large-scale photonic structures to enable complex devices composed of many emitters and photons.Photonic quantum information processors use multiple interacting photons to implement quantum computors, 1,2 simulators, 3,4 and networks. [5][6][7][8] These applications require efficient single photon sources coupled to photonic circuits that implement qubit interactions to create highly connected multi-qubit systems. [8][9][10][11] Scalable photonic quantum information processors require methods to integrate single photon sources with compact photonic devices that can combine many optical components. Such integration could enable complex quantum information processors in a compact solid-state material. [12][13][14] Silicon has many advantages as a material for integrated quantum photonic devices. It has a large refractive index that enables many photonic components to fit into a small device size. [15][16][17] Electrical contacts incorporated into the photonic structure can rapidly modulate and reconfigure

On‐Chip Integration of Single Photon Sources via Evanescent Coupling of Tapered Nanowires to SiN Waveguides

“…The devices showed waveguide coupling efficiencies of 12.2% (24.3% for both forward and backward directions) and single photon purities of 93%. Hybrid integration based on evanescent coupling has also been demonstrated; in this case, devices having appropriate geometries are either fabricated on the III‐V growth substrate and transferred to a silicon chip or the entire epitaxial layer is transferred and processing is done on silicon . A collection efficiency at the fiber facet of 3.2% was demonstrated with single photon purities of 67–75%, the low purity values associated with residual background emission due to above‐band pumping.…”

“…Finally, the evanescent approach described here takes advantage of the well‐controlled taper grown as part of the nanowire that contains only a single quantum dot. Hence, the spatial positioning of the single emitters is deterministic in contrast with previous evanescent coupling methods which used etched tapers in layers containing an ensemble of randomly positioned emitters.…”

Advanced Technologies for Quantum Photonic Devices Based on Epitaxial Quantum Dots

“…Coupling of quantum dot single‐photons into one of the MZI input waveguides relied on the chance spatial alignment of an individual dot to the former; without shaping of the GaAs to help funnel quantum dot emission into the input waveguide, a theoretical maximum collection efficiency of about 3% was predicted. Following this initial demonstration, incorporation onto silicon‐based photonic circuits of III–V nanophotonic geometries designed for enhanced collection efficiency has so far been explored primarily through two different approaches—one based on wafer‐bonding, and one based on pick‐and‐place techniques …”

“…b) InP nanobeam with embedded InAs QDs placed above a Si waveguide on a SiO 2 waveguide. Reproduced with permission . Copyright 2017, American Chemical Society.…”

Independent indistinguishable quantum light sources on a reconfigurable photonic integrated circuit

“…An alternative scheme is to use quantum emitters with naturally sub-Poissonian photon statistics within a waveguide circuit made of the emitter's host material. [17][18][19][20] It is also possible to evanescently couple the emitter to a low-loss PIC [21][22][23] and these schemes have verified the emission of single photons. However, for realising large scale and compact circuits, it will be necessary to integrate multiple sources of indistinguishable photons on the chip, as we demonstrate here.…”