Transfer-printed single-photon sources coupled to wire waveguides

Abstract

Photonic integrated circuits (PICs) are attractive platforms to perform large-scale quantum information processing. While highly-functional PICs (e.g. silicon based photonic-circuits) andhigh-performance single photon sources (SPSs, e.g. compound-semiconductor quantum dots (QDs)) have been independently demonstrated, their combination for single-photon-based applications has still been limited. This is largely due to the complexities of introducing SPSs into existing PIC platforms, which are generally realized with different materials and using distinct fabrication protocols. Here, we report a novel approach to combine SPSs and PICs prepared independently. We employ transfer printing, by which multiple desired SPSs can be integrated in a simple pick-and-place manner with a theoretical waveguide coupling efficiency >99%, fulfilling the demanding requirements of large-scale quantum applications. Experimentally, we demonstrated QD-based SPSs with high waveguide coupling efficiencies, together with the integration of two SPSs into a waveguide. Our approach will accelerate scalable fusion between modern PICs and cutting-edge quantum technologies.

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 …”

“…c) GaAs photonic crystal cavity containing InAs QDs, placed over a GaAs waveguide on a SiO 2 substrate, spaced from it by distance d , by way of a planarized spin‐on‐glass (SOG) layer. Reproduced with permission . Copyright 2018, Optical Society of America.…”

“…In the work by Katsumi et al., InAs quantum dot‐containing GaAs nanobeam photonic crystal cavities evanescently coupled to underlying GaAs waveguides were produced through a transfer‐printing process . Here, a polydimethylsiloxane (PDMS) stamp was used to lift suspended GaAs nanobeams from a processed GaAs wafer.…”

“…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, [226] and one based on pick-and-place techniques. [238][239][240][241][242]…”

“…Reproduced with permission. [242] Copyright 2018, Optical Society of America. d) Schematic of quantum memories based on diamond nanobeams with NV centers, coupled to SiN waveguides.…”