Perspectives on high-frequency nanomechanics, nanoacoustics, and nanophononics

Abstract

Nanomechanics, nanoacoustics, and nanophononics refer to the engineering of acoustic phonons and elastic waves at the nanoscale and their interactions with other excitations, such as magnons, electrons, and photons. This engineering enables the manipulation and control of solid-state properties that depend on the relative positions of atoms in a lattice. The access to advanced nanofabrication and novel characterization techniques enabled a fast development of the fields over the last decade. The applications of nanophononics include thermal management, ultrafast data processing, simulation, sensing, and the development of quantum technologies. In this review, we cover some of the milestones and breakthroughs and identify promising pathways of these emerging fields.

Coherent Acoustic Vibrational Spectrum of Single and Coupled Nanoresonators

“…Notably, previous summaries of nanoresonators at relatively lower vibrational frequencies have revealed a consistent trend: structures with higher vibrational frequencies tend to exhibit smaller quality factors. 2,68 This trend underscores the inverse relationship between the acoustic frequency and the ability of nanoresonators to sustain highquality vibrations. However, a notable advantage of highfrequency mechanical resonators is their potential to achieve the quantum ground state at relatively higher temperatures, characterized by T < hf/k B .…”

“…The investigation of vibrational lifetimes in nanoresonators is a dynamic and active research area. Numerous studies have focused on enhancing vibrational lifetimes to identify optimal candidates that exhibit extended lifetimes, especially in the field of optomechanics. , The pursuit of longer vibrational lifetimes is a key aspect of ongoing efforts to optimize the performance and reliability of nanoresonators. Furthermore, the vibrational damping provides detailed information about how the nanoresonator interact with their environment, which enables nanoresonators as superior nanoprobes. , …”

“…Confinement of acoustic phonons through phononic resonances in nanoresonators generates many interesting acoustic phenomena. Recent advancements in acoustic phonon engineering have enabled precise control and manipulation of the phonon dynamics in nanoscale structures, driving significant progress in nanoacoustics . Nanoacoustics offers insights into the impact of particle size, geometry, crystallinity, and surface conditions on the elastic properties of nanoscale objects. − …”

“…Recent advancements in acoustic phonon engineering have enabled precise control and manipulation of the phonon dynamics in nanoscale structures, driving significant progress in nanoacoustics. 2 Nanoacoustics offers insights into the impact of particle size, geometry, crystallinity, and surface conditions on the elastic properties of nanoscale objects. 3−5 Acoustic vibrations are ubiquitous in objects ranging from biological entities to inorganic nanoparticles (Figure 1a).…”

Enhanced efficiency of coherent acoustic phonon generation and detection using elliptical micropillars

“…Our study contributes to advancing the development of an efficient platform for exciting and detecting acoustic phonons. 19…”