Aluminum gallium arsenide-on-insulator (AlGaAsOI) exhibits large [Formula: see text] and [Formula: see text] optical nonlinearities, a wide tunable bandgap, low waveguide propagation loss, and a large thermo-optic coefficient, making it an exciting platform for integrated quantum photonics. With ultrabright sources of quantum light established in AlGaAsOI, the next step is to develop the critical building blocks for chip-scale quantum photonic circuits. Here we expand the quantum photonic toolbox for AlGaAsOI by demonstrating edge couplers, 3 dB splitters, tunable interferometers, and waveguide crossings with performance comparable to or exceeding silicon and silicon-nitride quantum photonic platforms. As a demonstration, we de-multiplex photonic qubits through an unbalanced interferometer, paving the route toward ultra-efficient and high-rate chip-scale demonstrations of photonic quantum computation and information applications.
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High-efficiency fiber-to-chip interface for aluminum nitride quantum photonics
Integrated nonlinear photonic circuits received rapid development in recent years, providing all-optical functionalities enabled by cavity-enhanced photon-photon interaction for classical and quantum applications. A high-efficiency fiber-to-chip interface is key to these integrated photonic circuits for quantum information tasks, as photon-loss is a major source that weakens quantum protocols. Here, overcoming material and fabrication limitation of thin-film aluminum nitride by adopting a stepwise waveguiding scheme, we demonstrate low-loss adiabatic fiber-optic couplers in aluminum nitride films with a substantial thickness (∼600 nm) for optimized nonlinear photon interaction. For telecom (1550 nm) and near-visible (780 nm) transverse magnetic-polarized light, the measured insertion loss of the fiber-optic coupler is -0.97 dB and -2.6 dB, respectively. Our results will facilitate the use of aluminum nitride integrated photonic circuits as efficient quantum resources for generation of entangled photons and squeezed light on microchips.
more » « less- Award ID(s):
- 1839177
- PAR ID:
- 10143371
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- OSA Continuum
- Volume:
- 3
- Issue:
- 4
- ISSN:
- 2578-7519
- Format(s):
- Medium: X Size: Article No. 952
- Size(s):
- Article No. 952
- Sponsoring Org:
- National Science Foundation
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