In this work, Lamb Wave Resonators (LWRs) based on 2 μm thin Y-cut LiNbO3 films have been fabricated using integrated fabrication process that defines IDTs (Inter Digital Transducers) on top surface and a partial Si cavity for a sacrificial layer on the bottom surface. We discuss the etch quality and its effects on the device's performance. For the first time, we present an optimized high-quality etched MEMS (Micro-electromechanical Systems) Resonator with smooth and vertical sidewalls on this material system, reporting the maximum Q-factor of 2500 at 846 MHz frequency. We observed that the resonator system has a Q-factor of 480 over the same frequency range when the etched surface has significant roughness and non-verticality. Q values of the device are greatly diminished by the presence of surface roughness and non-verticality of the etched edges. This truly highlights how important it is to have a high-quality etch profile for a piezoelectric material system like this so that the designed resonators can perform at their best.
Electric fields in a surface acoustic wave in a piezoelectric substrate can pattern charge in an adjacent graphene film via the acousto-electric effect and thus reconfigure the optical transmission in an unpatterned graphene metasurface
The performance of electronic systems for radio-frequency (RF) spectrum analysis is critical for agile radar and communications systems, ISR (intelligence, surveillance, and reconnaissance) operations in challenging electromagnetic (EM) environments, and EM-environment situational awareness. While considerable progress has been made in size, weight, and power (SWaP) and performance metrics in conventional RF technology platforms, fundamental limits make continued improvements increasingly difficult. Alternatively, we propose employing cascaded transduction processes in a chip-scale nano-optomechanical system (NOMS) to achieve a spectral sensor with exceptional signal-linearity, high dynamic range, narrow spectral resolution and ultra-fast sweep times. By leveraging the optimal capabilities of photons and phonons, the system we pursue in this work has performance metrics scalable well beyond the fundamental limitations inherent to all electronic systems. In our device architecture, information processing is performed on wide-bandwidth RF-modulated optical signals by photon-mediated phononic transduction of the modulation to the acoustical-domain for narrow-band filtering, and then back to the optical-domain by phonon-mediated phase modulation (the reverse process). Here, we rely on photonics to efficiently distribute signals for parallel processing, and on phononics for effective and flexible RF-frequency manipulation. This technology is used to create RF-filters that are insensitive to the optical wavelength, with wide center frequency bandwidth selectivity (1-100GHz), ultra-narrow filter bandwidth (1-100MHz), and high dynamic range (70dB), which we will present. Additionally, using this filter as a building block, we will discuss current results and progress toward demonstrating a multichannel-filter with a bandwidth of < 10MHz per channel, while minimizing cumulative optical/acoustic/optical transduced insertion-loss to ideally < 10dB. These proposed metric represent significant improvements over RF-platforms.
We present progress towards the development of novel hybrid photonic-phononic oscillator technologies in both nanoscale silicon photonics and in fiber optic systems. These systems utilize traveling-wave photon-phonon couplings involving both stimulated Brillouin scattering processes (SBS). We explore numerous geometries that have enabled large forward-SBS processes in nanoscale silicon waveguides for the first time, and examine new approaches to achieving integrated Brillouin based signal processing.
Optical stochastic cooling (OSC) holds significant promise for cooling of charged particle beams to enhance
the luminosity of high energy colliders. This paper describes the conceptual design and requirements for an
interferometer to be built for an OSC demonstration experiment with stored electrons at the MIT-Bates South
Hall Ring. The paper will present an overview of the optical and charged particle beamlines, the intensity
detection system and the phase stabilizing feedback loop.