Cryo-compatible opto-mechanical low-voltage phase-modulator integrated with superconducting single-photon detectors.

Photonic integrated circuits (PICs) have enabled novel functionality in quantum optics, quantum information processing and quantum communication. PICs based on Silicon Nitride (SiN) provide low-loss passive components and are compatible with efficient superconducting nanowire single-photon detectors (SNSPDs). For realizing functional quantum photonic systems, the integration with active phase-shifters is needed which is challenging at the cryogenic temperatures needed for operating SNSPDs.

Optoelectromechanical phase shifter with low insertion loss and a 13π tuning range.

We present an on-chip optoectromechanical phase shifter with low insertion loss and low half-wave voltage using a silicon nitride platform. The device is based on a slot waveguide in which the electrostatic displacement of mechanical structures results in a change of the effective refractive index. We achieve insertion loss below 0.

Tantalum pentoxide nanophotonic circuits for integrated quantum technology.

Nanophotonics holds great promise for integrated quantum technologies, but realizing all functionalities for processing quantum states of light in optical waveguides poses an outstanding challenge. Here we show that tantalum pentoxide-on-insulator offers significant advantages for such purpose and experimentally demonstrate crucial photonic integrated circuit components. Exploiting advanced nanophotonic design and state-of-the-art nanofabrication processes, we realize low-loss waveguiding with 1 dB/cm propagation loss, efficient optical fiber-chip interfaces with more than 100 nm bandwidth, micro-ring resonators with quality factors of 357,200 and tunable directional couplers.