Two-Photon Interference from the Far-Field Emission of Chip-Integrated Cavity-Coupled Emitters

Abstract

ABSTRACT. Interactions between solid-state quantum emitters and cavities are important for a broad range of applications in quantum communication, linear optical quantum computing, nonlinear photonics, and photonic quantum simulation. These applications often require combining many devices on a single chip with identical emission wavelengths in order to generate two-photon interference, the primary mechanism for achieving effective photon-photon interactions. Such integration remains extremely challenging due to inhomogeneous broadening and fabrication errors that randomize the resonant frequencies of both the emitters and cavities. In this letter we demonstrate two-photon interference from independent cavity-coupled emitters on the same chip, providing a potential solution to this long-standing problem. We overcome spectral mismatch between different cavities due to fabrication errors by depositing and locally evaporating a thin layer of condensed nitrogen. We integrate optical heaters to tune individual dots within each cavity to the same resonance with better than 3 µeV of precision. Combining these tuning methods, we demonstrate two-photon interference between two devices spaced by less than 15 µm on the same chip with a post-selected visibility of 33%. These results pave the way to integrate multiple quantum light sources on the same chip to develop quantum photonic devices.

Coherence Properties of Molecular Single Photons for Quantum Networks

“…This configuration allows for a measurement of the photon statistics in a single output arm and has been used for a characterization of single photons before [7,[25][26][27]. The corresponding measurement is shown in Fig.…”

Mesa-top quantum dot single photon emitter arrays: Growth, optical characteristics, and the simulated optical response of integrated dielectric nanoantenna-waveguide systems

“…Experimentally this is enabled by overgrowth of the appropriate material, here GaAs, on the MTSQD array until planarization. The resulting system of buried SQDs with known spatial geometry is ideally suited for subsequent lithographic fabrication of optical elements using either of the two current approaches: micropillar that enables waveguiding and collection in the vertical geometry [7][8][9][10] , and particularly the 2D photonic crystal platform that enables manipulation and guidance of the single photons in the horizontal geometry [15][16][17][18][19][20]68 . Here we investigate a third approach involving the use of the collective resonance of designed systems of interacting nanoscale DBBs that allow manipulation of light on the micron scale beyond the usual diffraction limit 57 .…”

“…For the horizontal architecture, with the advancements in nanoscale lithography and etching over large areas, 2D photonic crystal platform has been shown to manipulate single photon emission (rate, purity etc.) [15][16][17][18][19][20] and build on-chip interconnected structures 19,20 . In both approaches, so far the reported studies are invariably on pre-selected single QD -cavity / waveguide single units, not array.…”

“…The work horse has been the GaAs(001)/InGaAs material system that, on planar GaAs(001) spontaneously forms 3D islands for ~1.6 ML deposition of InAs. The SAQDs have also been incorporated in coupled SPS-cavity [7][8][9][10]17,19,20 , SPS-waveguide 15,16,18 , and SPS-cavity-waveguide 19 systems. However, the random nature of SAQD formation in space and time, inherent to their spontaneous initiation, leads to randomness in their location and considerable variation in island size, shape, and composition that results in unacceptable spectral non-uniformity in the SAQD emission [43][44][45][46][47] .…”

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

“…Local tuning methods based on temperature, strain, and quantum confined Stark effect could provide additional fine-tuning to compensate for small residual spectral mismatch as well as to control on-chip interactions. [36][37][38] In the current device, the grating couplers are the most significant source of loss. Improved grating couplers using partial etching can achieve greater than 90% efficiency.…”