Hybrid Integration of Deterministic Quantum Dot‐Based Single‐Photon Sources with CMOS‐Compatible Silicon Carbide Photonics

Abstract

Thin film 4H-silicon carbide (4H-SiC) is emerging as a contender for realizing large-scale optical quantum circuits due to its high CMOS technology compatibility and large optical nonlinearities. Though, challenges remain in producing wafer-scale 4H-SiC thin film on insulator (4H-SiCOI) for dense integration of photonic circuits, and in efficient coupling of deterministic quantum emitters that are essential for scalable quantum photonics. Here, hybrid integration of self-assembled InGaAs quantum dot (QD)-based single-photon sources (SPSs) with wafer-scale 4H-SiC photonic chips prepared by ion slicing technique is demonstrated. By designing a bilayer vertical coupler, generation and highly efficient routing of single-photon emission in the hybrid quantum photonic chip are realized. Furthermore, a chip-integrated beamsplitter operation for triggered single photons through fabricating a 1 × 2 multimode interferometer (MMI) with a symmetric power splitting ratio of 50:50 is realized. The successful demonstration of heterogeneously integrating QD-based SPSs on 4H-SiC photonic chip prepared by ion slicing technique constitutes an important step toward CMOS-compatible, fast reconfigurable quantum photonic circuits with deterministic SPSs.

Highly Accurate Docking of a Photonic Crystal Nanolaser to a SiNx Waveguide by Transfer Printing

“…The second modification involved connecting a tapered beam on the side with fewer PhCs, which efficiently led to energy leakage coupling to the SiN x waveguide. In Figure a, the width of this tapered beam shrinks from w NB to 0 within the length L , which is a widely used mode converter design ,,,, for optical coupling in PICs. The third modification was setting a groove portion with a depth g on one side of the NB, forming a gap between the waveguide when docked to the waveguide.…”

“…This improvement allows it to achieve sub-wavelength-level misalignment of wire-to-wire integration in PICs, as well as suitable for different dielectric or metallic nanophotonic structures ,,− onto different platforms. For example, highly efficient coupling can be achieved by integrating nanowires − or photonic crystal (PhC) nanobeam (NB) − light sources with silicon-based waveguides. Various alignment marks ,,− have been used to achieve misalignments of less than hundreds of nanometers, and careful feedback control associated with multiple marks has been reported to achieve misalignments of less than 100 nm .…”

Epitaxial quantum dots: a semiconductor launchpad for photonic quantum technologies

“…Hybrid integration of quantum dots into other material platforms offers a flexible modular approach to building the reconfigurable QPIC, which is promising to exploit the advantage of different material platforms [5–7,203–206,239] . Hybrid integration of quantum-dot emitters into photonic nanostructures on Si [204,240–242] , Si3normalN4 [32,206,243,244] , SiON [227] , GaAs [205] , LiNbO3 [203] , and SiC [243,245] platforms has been demonstrated. Figures 6(e)–6(h) represent some examples of hybrid integration into various material platforms exploiting three commonly used integration technologies: III–V quantum dots embedded in nanowaveguides have been integrated onto LiNbO3 [Fig.…”

“…As mentioned above, photon switches relying on strain tuning in a hybrid SiN-AlN have also been achieved, improving the device operation speed to 120 MHz. Apart from materials listed in Table 1, AlN [246–248] and SiC [243,245,249] have emerged as contenders for integrated quantum photonics. Both AlN [250] and SiC [251,252] feature a large transparent window and a large Pockels coefficient, holding great promise for constructing reconfigurable quantum photonic devices that are compatible with quantum dot emitters.…”

Efficient Photonic Integration of Diamond Color Centers and Thin-Film Lithium Niobate

“…Here, we demonstrate efficient heterogeneous integration of a diamond nanobeam featuring incorporated SiV color centers with a TFLN platform using a mechanical pick-and-place approach. ,− By precisely placing double-tapered diamond nanobeams, we demonstrate the bridging of a gapped TFLN waveguide with a diamond-to-LN transmission efficiency of 92 ± 11% per facet at 737 nm, corresponding to the SiV ZPL wavelength, averaged across multiple measurements. We find an approximately 2-fold improvement in ZPL photon extraction via integrated TFLN collection channels compared with that via out-of-plane collection from the same device.…”