With recent and rapid progress, compound semiconductor on insulator (CSOI) photonics is transforming quantum technologies by providing new functionalities and capabilities not possible with traditional, silicon-based photonics. In this talk, I will discuss how we can leverage the strong nonlinearities and low propagation loss of CSOI photonics to engineer and manipulate complex quantum photonic states on chip. I will present recent results on creating indistinguishable arrays of entangled-pair and squeezed light sources pumped with continuous wave and pulsed excitation, on-chip line-by-line quantum frequency comb shaping, and tunable microring resonator arrays for frequency bin qudits.
With recent and rapid progress, compound semiconductor on insulator (CSOI) photonics is transforming quantum technologies by providing new functionalities and capabilities not possible with traditional, silicon-based photonics. In this talk, I will discuss how we can leverage the strong nonlinearities and low propagation loss of CSOI photonics to engineer and manipulate complex quantum photonic states on chip. I will present recent results on creating indistinguishable arrays of entangled-pair and squeezed light sources pumped with continuous wave and pulsed excitation, on-chip line-by-line quantum frequency comb shaping, and tunable microring resonator arrays for frequency bin qudits.
With recent and rapid progress, compound semiconductor on insulator (CSOI) photonics is transforming quantum technologies by providing new functionalities and capabilities not possible with traditional, silicon-based photonics. In this talk, I will discuss how we can leverage the strong nonlinearities and low propagation loss of AlGaAs-on-insulator photonics for quantum computing and communications. I will present recent results on entangled-pair and squeezed-light generation, on-chip frequency bin processors based on integrated modulators and pulse shapers, and architectures for high-dimensional graph-state generation for distributing entanglement across quantum networks.
Integrated quantum photonics can realize and process optical entangled quantum states in highly compact, robust, and scalable chips thereby enabling chip scale implementations of long-distance quantum-secured communication, quantum-accelerated information processing, and non-classical metrology [1]. Notably, all previous on-chip entangled quantum photonic sources have relied on an external laser to excite nonlinear parametric processes, thereby making these systems overall non-reproducible, bulky, impractical, and thus unsuitable for out-of-lab use as well as production at large scale [2]. To date, the major challenge inhibiting a fully on-chip quantum light system is to integrate a stable, tunable laser together with a high rejection filter that eliminates laser sideband noise [3], [4] and a nonlinear parametric source of entangled photons. Fig. 1 A) laser-integrated photonic quantum light source of frequency-bin entangled photon states: an electrically pumped inp gain-section, i.e. A reflective semiconductor optical amplifier (rsoa) providing optical gain, is coupled to a si3n4 chip containing a three microring resonator (r1, r2, and r3) vernier filter and a mach-zehnder interferometer (mzi) with a sagnac loop mirror. B) measurements utilizing single photon detectors allowed to determine an smsr≈ 112 db, and an ase suppression of> 56 db. C) car for respective frequency pairs for an excitation power of 3.9 mw. D) density matrices of two-dimensional (qubit) and three-dimensional (qutrit) frequency-bin entangled states reconstructed via quantum state tomography (qst).
Quantum technology promises to deliver quantum computers, unbreakable communication and ultra-sensitive sensors. Quantum photonics is one of the prominent platforms of quantum technology which utilizes photons – often called flying qubits. Entanglement generated from a photon-pair source is a crucial resource for many quantum photonic implementations, for example, an entanglement-based global quantum network and metrology beyond classical limits. Here, we will discuss our recent results of chip-scale photon-pair sources in silicon photonics. These results are focused on improving brightness, spectral purity and indistinguishability of the photon-pair sources, for example, by engineering photonic structures and temporal pulse shaping. We have found that both methods have trade-offs among brightness, spectral purity and indistinguishability. Additionally, we have observed that generating a high-fidelity quantum state using a quantum photonic circuit requires sufficient isolation between the nonlinear photon-pair sources and the linear photonic circuit. It is crucial to remove the nonlinear effect of the strong pump both before and after the sources to limit the spurious photon-pair generation which contaminates the target quantum state.
Nonclassical states of light are an essential resource for many emerging quantum technologies and applications ranging from information processing, encrypted communications, and networking to sensing, metrology, and imaging. Nonlinear optical processes in solid-state materials are widely used for generating quantum light, including single photons, entangled-photon pairs, and quadrature-squeezed states. Recent advances in nonlinear photonics have enabled the functionality of benchtop nonlinear instruments to be scaled down to a single chip without sacrificing efficiency or degrading the key performance metrics. The dramatic improvement in the size, weight, power, cost, and stability enabled by photonic integrated circuits has been essential for enabling the chip-scale generation, manipulation, and detection of quantum light at a steadily increasing degree of complexity and scale. Within the last decade, the authors have seen the progression from few-component photonic circuits operating on two photons to arrays of 18 identical heralded single-photon sources and reconfigurable devices operating with more than 650 components for multidimensional entanglement and arbitrary two-photon quantum gates. In this review, the authors summarize the history and recent key technological developments of chip-scale nonlinear quantum light generation based on integrated nonlinear photonics, recent advances in heterogeneous integrated methods, and approaches for system-level integration and demonstrated applications.
The ability to generate and detect quantum states of light on a single integrated photonic device is essential to scale quantum photonics into useful quantum technologies. Integrating the required capabilities into complementary-metal-oxide-semiconductor compatible monolithic chips can reduce cost and unlock new functionality through miniaturisation. In this work we demonstrate a single silicon-on-insulator photonic integrated circuit for the monolithic generation and detection of quantum light on a commercially available platform that operates entirely at room temperature. Specifically, we leverage spontaneous four-wave mixing in silicon waveguides to produce squeezed light which is subsequently detected by photodiodes operating in a pulsed homodyne detector configuration on the same chip as the source. We directly measure 0.25(1) dB of squeezing, including contributions from waveguide propagation loss and detection inefficiency, and include a detailed analysis of the impact of nonlinear loss on the squeezing levels achievable using this platform.
3C-silicon carbide-on-insulator (3C-SiCOI) is an emerging photonic platform for integrated quantum photonics due to its moderate second- and third-order optical nonlinearities, wide bandgap energy, and compatibility with silicon complementary metal-oxide-semiconductor technologies. In this work, we report our progress in photon-pair generation and quantum state manipulation on the 3C-SiCOI platform. We demonstrate the generation of photon pairs through the spontaneous parametric down-conversion process using modal phase-matching in an elliptical microring resonator on this platform. We will present the design principle and recent progress of our experimental work.