Abstract: Devices employing Brillouin interactions that can be modified by acoustoelectric (AE) interactions, thereby enabling control over the devices' nonlinear optical susceptibility, are described. Modification of the phonon dissipation rates through application of quasistatic electric fields in the semiconductor can improve the performance of Brillouin photonic devices. These AE Brillouin interactions allow for local control of the phonon phase velocity and thus the Brillouin scattering frequencies, providing an electronic means to compensate for inhomogeneous broadening that occurs over large length scales. Moreover, these AE Brillouin interactions allow Brillouin scattering processes to employ phonon coherence lengths that can achieve parity with and even exceed those of the photons, enabling fully coherent three-wave parametric-like processes.

Abstract: Various reconfigurable phononic devices, including phase shifters, mirrors, Mach Zehnder interferometers, memories, and transducers for use in both classical and quantum computing systems are disclosed. The individual phononic devices may be combined in various configurations to implement desired, more complex functionality. The phononic devices may be coupled together to implement the desired functionality using phononic waveguides. The phononic devices include one or more phase shifters that are operationally based on either hyperelasticity or a moving boundary effect.

Abstract: Various reconfigurable phononic devices, including phase shifters, mirrors, Mach Zehnder interferometers, memories, and transducers for use in both classical and quantum computing systems are disclosed. The individual phononic devices may be combined in various configurations to implement desired, more complex functionality. The phononic devices may be coupled together to implement the desired functionality using phononic waveguides. The phononic devices include one or more phase shifters that are operationally based on either hyperelasticity or a moving boundary effect.

Abstract: Systems and methods for hybrid integration of ultra-low loss waveguide photonic circuits with various efficient on-chip elements are described. The photonic circuits can integrate various elements including (but not limited to): gain, modulation, detection, and nonlinear optical elements. The integrated photonic chips can be manufactured in a flexible, reconfigurable, 3D heterogeneous platform. The integrated photonic chips can cover wavelength ranges from the visible wavelength to infrared wavelength.

Abstract: An acoustoelectric amplifier and a number of corresponding devices are disclosed, along with methods for making the same. The acoustoelectric amplifier employs wafer-scale bonding to heterogeneously integrate an epitaxial III-V semiconductor stack and a piezoelectric layer. To increase the acoustic gain with low power dissipation, the electromechanical coupling coefficient (k2) of the piezoelectric layer should be high to increase the acoustoelectric interaction strength. The semiconductor mobility should be high to reduce the voltage required to increase the carrier drift velocity. The conductivity-thickness product should be low to prevent screening of the acoustoelectric interaction. The acoustoelectric amplifier or its corresponding material structure may be used to form circulators, isolators, oscillators, mixers, and correlators, while interconnecting waveguides may be formed of the piezoelectric layer or the semiconductor stack.

Abstract: Josephson junctions are the main circuit element of superconducting quantum information devices due to their nonlinear inductance properties and fabrication scalability. However, large scale integration necessarily depends on high fidelity and high yielding fabrication of Josephson junctions. The standard Josephson junction technique depends on a submicron suspended resist Dolan bridge that tends to be very fragile and fractures during the fabrication process. The present invention is directed to a new tunnel junction resist mask that incorporates stress-relief channels to reduce the intrinsic stress of the resist, thereby increasing the survivability of the Dolan bridge during device processing, resulting in higher Josephson junction yield.

Abstract: A CMOS-compatible actuator platform for implementing phase, amplitude, and frequency modulation in silicon nitride photonic integrated circuits via piezo-optomechanical coupling using tightly mechanically coupled aluminum nitride actuators is disclosed. The platform, which may be fabricated in a CMOS foundry, enables scalable active photonic integrated circuits for visible wavelengths, and the piezoelectric actuation functions without performance degradation down to cryogenic operating temperatures. A number of devices are possible, including ring modulator devices, phase shifter devices, Mach-Zehnder interferometer devices, directional coupler devices (including tunable directional coupler devices), and acousto-optic modulator and frequency shifter devices, each of which can employ the same AlN actuator platform. As all of these devices can be built on the same AlN actuator platform, numerous optical functions can be implemented on a single die.

Abstract: A hybrid quantum system performs high-fidelity quantum state transduction between a superconducting (SC) microwave qubit and the ground state spin system of a solid-state artificial atom. This transduction is mediated via an acoustic bus connected by piezoelectric transducers to the SC microwave qubit. For SC circuit qubits and diamond silicon vacancy centers in an optimized phononic cavity, the system can achieve quantum state transduction with fidelity exceeding 99% at a MHz-scale bandwidth. By combining the complementary strengths of SC circuit quantum computing and artificial atoms, the hybrid quantum system provides high-fidelity qubit gates with long-lived quantum memory, high-fidelity measurement, large qubit number, reconfigurable qubit connectivity, and high-fidelity state and gate teleportation through optical quantum networks.

Abstract: The invention is directed to a device and method to engineer the superconducting transition width by suppressing the phonon populations responsible for the Cooper-pair decoherence below the superconducting transition temperature via phononic bandgap engineering. The device uses phononic crystals to engineer a phononic frequency gap that suppresses the decohering thermal phonon population just below the Cooper-frequency, and thus the normal conduction electron population. For example, such engineering can relax the cooling requirements for a variety of circuits yielding higher operational quality factors for superconducting electronics and interconnects.

Abstract: The invention is directed to a device and method to engineer the superconducting transition width by suppressing the phonon populations responsible for the Cooper-pair decoherence below the superconducting transition temperature via phononic bandgap engineering. The device uses phononic crystals to engineer a phononic frequency gap that suppresses the decohering thermal phonon population just below the Cooper-frequency, and thus the normal conduction electron population. For example, such engineering can relax the cooling requirements for a variety of circuits yielding higher operational quality factors for superconducting electronics and interconnects.

Abstract: The present invention relates to tunable microresonators, as well as methods of designing and tuning such resonators. In particular, tuning includes applying an electrical bias to the resonator, thereby shifting the resonant frequency.

Abstract: A high-brightness squeezed light source includes a plurality of light squeezing elements and a photonic summing device. The light squeezing elements each output respective squeezed light responsive to receipt of unsqueezed light. The photonic summing device receives the squeezed light output by each of the light squeezing elements and coherently adds the squeezed light to generate a high-brightness squeezed light output. The high-brightness squeezed light output has a greater brightness than the outputs of the light squeezing elements, and a same degree of squeezing as one or more of the outputs of the light squeezing elements.

Abstract: A quantum communication system includes a first quantum transceiver, a second quantum transceiver, and a quantum communication mediator (QCM) system. The transceivers have different resonant frequencies or physical systems. The QCM system receives an initial quantum signal from the first quantum transceiver. The QCM system transfers a quantum state of the initial quantum signal to a first mechanical signal and then from the first mechanical signal to a first pair of optical signals by way of a first three-wave mixing process. The QCM transfers the quantum state to a second pair of optical signals from the first pair by way of a four-wave mixing process. The QCM transfers the quantum state from the second pair of optical signals to a second mechanical signal by way of a second three-wave mixing process. The QCM transfers the quantum state from the second mechanical signal to a final quantum signal by mechanical transduction.

Abstract: A hybrid quantum system performs high-fidelity quantum state transduction between a superconducting (SC) microwave qubit and the ground state spin system of a solid-state artificial atom. This transduction is mediated via an acoustic bus connected by piezoelectric transducers to the SC microwave qubit. For SC circuit qubits and diamond silicon vacancy centers in an optimized phononic cavity, the system can achieve quantum state transduction with fidelity exceeding 99% at a MHz-scale bandwidth. By combining the complementary strengths of SC circuit quantum computing and artificial atoms, the hybrid quantum system provides high-fidelity qubit gates with long-lived quantum memory, high-fidelity measurement, large qubit number, reconfigurable qubit connectivity, and high-fidelity state and gate teleportation through optical quantum networks.

Abstract: A focusing interdigital transducer (IDT) and corresponding single- and dual-port piezoelectric devices are disclosed. The focusing interdigital transducer, which generates Lamé acoustic waves, permits operation at significantly higher frequencies than those possible with traditional IDTs. The focusing IDT employs multiple arced fingers formed both above and below the piezoelectric layer to improve coupling efficiency by coupling through both the e31 and e33 piezoelectric coefficients to the piezoelectric layer. By optimizing both anchor design and location, acoustic wave losses are minimized, thereby improving the device's quality factor Q. Through proper bus design and selection of the number of IDT fingers, a device's impedance can be tuned for a given application. The focusing IDTs may be used in single-port filter devices and dual-port transformer devices. The single- and dual-port devices may operate at a single frequency, at two frequencies, or over a band of frequencies.

Abstract: An amplifying radiofrequency device includes a piezoelectric film and a semiconductor amplifier layer. The piezoelectric film is conformed as an acoustic waveguide. The piezoelectric film has a principal acoustic propagation direction parallel to the principal conduction direction of the amplifier layer. Interdigitated transducers are positioned on the piezoelectric film to respectively launch an acoustic wave in response to an input RF signal, and transduce the acoustic wave back to an output RF signal. There is a distance of less than the acoustic wavelength between the semiconductor amplifier layer and the piezoelectric film. The piezoelectric film has a thickness of less than the acoustic wavelength. According to a method for making such a device, a stack of III-V layers is epitaxially grown on a III-V substrate, wherein the stack comprises a first etch stop layer, a second etch stop layer, an amplifier layer, and a contact layer. The stack is bonded to a lithium niobate film.

Abstract: An electro-acoustic device includes a plurality of suspended, piezoelectric, acoustically waveguiding membranes supported in a common plane. An input transducer coupled to one of the waveguiding membranes converts input electrical signals to traveling-wave acoustic signals. An output transducer coupled to one of the waveguiding membranes converts acoustic signals to electrical signals. At least two of the waveguiding membrane have parallel straight sections that are longer than a guided acoustic wavelength and that are mutually separated by an air gap having a width less than the guided acoustic wavelength.

Abstract: A micromechanical resonator is disclosed. The resonator includes a resonant micromechanical element. A film of annealable material deposited on a facial surface of the element. In one instance, the resonance of the element can be adjusting by using a feedback loop to control annealing of the deposited film.

Abstract: A radio frequency (RF) receiver comprises a passive impedance transforming voltage amplifier and a resonant, latching micromechanical switch having a deflectable bridge, an RF actuation electrode receivingly connected to the amplifier, and a DC bias electrode positioned to latch the switch in a closed position by electrostatic attraction when energized by a suitable voltage. The bridge is configured with a mechanical mode of vibration that periodically urges the switch toward the closed position.

Abstract: The present application relates to vertically integrated assemblies including a MEMS-based optomechanical architecture. In some embodiments, the assembly includes a MEMS/optoelectronic module, an emitter module, and a detector module, where these modules are vertically integrated. Methods of fabricating such assemblies are also described herein.