Abstract: In some embodiments, a device for generating mid-infrared radiation is provided. The device may include a thin film quadratic nonlinear waveguide formed on a mid-infrared transparent cladding by a thin film material of a predetermined film thickness, the waveguide having a predetermined etch depth and a predetermined top width. At least one of the predetermined film thickness, the predetermined etch depth, and the predetermined top width may be tuned for the device to generate a coherent idler wave as a mid-infrared radiation from a fixed pump wave and a tunable signal wave.

Abstract: A fault tolerant quantum computer is implemented using hybrid acoustic-electric qubits or electromagnetic qubits, as a few examples. A control circuit includes symmetrically arranged asymmetrically threaded superconducting quantum interference devices (ATSs) that excite phonons in a resonator by driving a storage mode of the resonator and dissipate phonons from the resonator via an open transmission line coupled to the control circuit, wherein the open transmission line is configured to absorb photons from a dump mode of the control circuit. The symmetric ATSs are arranged such that undesirable terms in respective Hamiltonians for the ATSs individually, cancel each other out when combined in the symmetric configuration.

Abstract: In an integrated optical device, squeezed light is used internally to effectively increase an optical modulation effect. One exemplary device operates by squeezing the light at the input, then sending it through an electro-optic stage where its phase picks up the signal of interest, and finally anti-squeezing it to obtain a displaced coherent state. Thus the displacement is amplified by the level of squeezing that is achieved inside the device and it is thereby less sensitive to loss. Since this device behaves simply as an electro-optic modulator, albeit one with an exponentially enhanced sensitivity, no extra considerations are needed to integrate the modulator into a system. Such devices can be operated as modulators or as sensors, and can make use of optical phase shift effects other than the electro-optic effect.

Abstract: Improved quantum transducers based on ensembles of quantum emitters are provided. This work improves the efficiencies of such transducers by compensating for the detrimental effects of inhomogeneous broadening of transition frequencies in such systems. This approach is built upon the insight that the temporal shape of the drive supplying the energy required for transduction can be experimentally tuned. Hence, it is an additional degree of freedom for designing efficient transducers. We pose the design of the drive as a scattering theory optimization problem, where the transduction efficiency is the quantity being maximized, and employ numerical optimization techniques to solve it.

Abstract: A coupled storage qubit nanomechanical resonator in a processing qubit superconducting circuit is provided that includes a phononic crystal resonator (PCR) film disposed on a substrate, where the PCR film includes a defect mode in a bandgap of the PCR film where a storage qubit is encoded, a pair of electrodes generate voltages within the PCR film, where the defect is dimensioned to support a unique electrical potential generated by a local mechanical phonon mode of the PCR film, where a unique resonance frequency that is dependent on the defect dimensions is output from the PCR film, a coupling capacitor that is coupled to the PCR film, where the coupling capacitor is disposed to receive the output unique resonance frequency, and a processing qubit, where the processing qubit is capacitively coupled to the PCR film by the coupling capacitor, where the storage qubits are connected to the processing qubits.

Abstract: An optical modulator with a wide aperture, high acceptance angle, low required drive voltages and high operating frequency is provided. The modulator relies on the photoelastic effect and makes use of mechanical resonance in order to improve efficiency. The acoustic excitation and optical propagation path are nominally co-aligned, so the required symmetry breaking is provided by having the modulator material be optically and/or mechanically anisotropic. Such a modulator can be used to enable efficient and low-cost per-pixel optical ranging and speed sensing.

Abstract: A doubly resonant electro-optic converter is provided. An optical resonator and a microwave resonator are disposed such that fields from the two resonators can interact in an electro-optic active medium. The optical resonator is a planar photonic crystal optical resonator, and the microwave resonator is at least partially superconducting in operation. The active medium has a second order nonlinearity capable of generating a sum frequency signal and/or a difference frequency signal from the optical and microwave fields. The resulting structure has both quantum and classical applications.

Abstract: A doubly resonant electro-optic converter is provided. An optical resonator and a microwave resonator are disposed such that fields from the two resonators can interact in an electro-optic active medium. The optical resonator is a planar photonic crystal optical resonator, and the microwave resonator is at least partially superconducting in operation. The active medium has a second order nonlinearity capable of generating a sum frequency signal and/or a difference frequency signal from the optical and microwave fields. The resulting structure has both quantum and classical applications.