All optical operation of a superconducting photonic interface

Abstract

Advanced electro-optic processing combines electrical control with optical modulation and detection. For quantum photonic applications these processes must be carried out at the single photon level with high efficiency and low noise. Integrated quantum photonics has made great strides achieving single photon manipulation by combining key components on integrated chips which are operated by external driving electronics. Nevertheless, electrical interconnects between driving electronics and the electro-optic components, some of which require cryogenic operating conditions, can introduce parasitic effects. Here we show an all-optical interface which simultaneously delivers the operation power to, and extracts the measurement signal from, an advanced photonic circuit, namely, bias and readout of a superconducting nanowire single photon detector (SNSPD) on a single stage in a 1K cryostat. To do so, we supply all power for the single photon detector, output signal conditioning, and electro-optic readout using optical interconnects alone, thereby fully decoupling the cryogenic circuitry from the external environment. This removes the need to heatsink electrical connections, and potentially offers low-loss, high-bandwidth signal processing. This method opens the possibility to operate other advanced electrically decoupled photonic circuits such as optical control and readout of superconducting circuits, and feedforward for photonic quantum computing.

Pyroelectric influence on lithium niobate during the thermal transition for cryogenic integrated photonics

“…Integrated superconducting single-photon detectors are successfully shown for weakly confined waveguide structures [18][19][20], and as well on thin film lithium niobate [8,21]. Electro-optic modulators can be used to read out superconducting devices [22,23], and are integrated together with superconducting detectors [8]. In addition, nonlinear frequency conversion processes have been established at cryogenic temperatures, such as second harmonic generation in periodically poled waveguides [24], and cryogenic transducers for terahertz generation by optical rectification [25][26][27].…”