High Coherence Quantum Phononic Circuits
Abstract
Efficient utilization of long-lived, high-frequency phonons could open the door to powerful new quantum sensors, scalable solid-state quantum memories, and high fidelity quantum transduction. For example, information storage at second timescales could be achieved with further mastery of dissipation and decoherence in quantum phononic materials and devices at cryogenic temperatures. Mass sensors with unrivaled precision can be created by harnessing such extraordinary phonon coherence within new device geometries. Efficient microwave-to-optical conversion and high-fidelity optical readout of phonons become possible by applying new strategies to shape and enhance phonon-mediated interactions. However, to utilize the potential offered by the nascent field of quantum phononics, we must fully exploit phononic materials and device physics as we explore new hardware-efficient strategies for mechanical devices in the quantum regime. Our interdisciplinary team will explore new materials, devices, and hybrid quantum circuits to manipulate phononic states and to control their dissipation and dephasing with the objective of exploiting long-lived phonons for quantum memories, sensors, and low loss delay lines. New microwave and optical spectroscopic tools will also be developed to gain fundamental understanding of phonon dissipation at different energy scales and pinpoint the sources of phonon dephasing associated with materials, surfaces, mode profiles, phonon density of states, and the impact of linear and nonlinear coupling to other circuit elements. Materials of strong piezoelectricity are central to this MURI program as they provide a platform shared by all team members for achieving strong linear coupling of phonons to quantum microwave circuits as well photonic circuits for quantum phonon controls. They also introduce nonlinearities and undesired phonon losses that must be thoroughly investigated and controlled. As the team optimize materials known to have strong pieoelectricity, new ferroelectric materials of even stronger piezoelectric strength such as transition metal doped III-nitride will be grown and evaluated throughout this program. New heterostructures with distributed acoustic impedance or controlled nitrogen isotopes will be introduced for tailoring the phonon spectra and electron-phonon interactions. By iterating materials, metrology and devices among the team members, we aim to identify quantum phononic structures with extended coherence readily integratable with superconducting qubits and photonic circuitry. With long-lived phonons and strong electro-mechanical coupling, we will realize universal quantum control of phononic modes and multimode quantum memories through robust gate operation and error correction schemes. We will introduce ancillary superconducting qubits including transmons and fluxonium to mediate the control of various phonon modes, including bulk acoustic modes, surface acoustic modes, and nanomechanical resonator arrays. Faster phonon gates will be also developed by harnessing the Kerr nonlinearity of superconductors. Building on these advances, robust and efficient quantum phonon control and error correction schemes will be developed over multimode phononic devices. Our overarching goal is to establish scalable phononic circuits as building blocks for quantum state processing and quantum sensing with encoded phononic states.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 06, 2024
- Source ID
- FA95502310338
Entities
People
- Thomas Rakich
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- Yale University