Related papers: Engineering nanoscale hypersonic phonon transport
Graphene grain boundaries are known to affect phonon transport and thermal conductivity, suggesting that they may be used to engineer the phononic properties of graphene. Here, the effect of two buckled grain boundaries on long-wavelength…
Understanding the effect of vibrations in optically active nano systems is crucial for successfully implementing applications in molecular-based electro-optical devices, quantum information communications, single photon sources, and…
Phonon modes at microwave frequencies can be cooled to their quantum ground state using conventional cryogenic refrigeration, providing a convenient way to study and manipulate quantum states at the single phonon level. Phonons are of…
Controlling long-lived mechanical oscillators in the quantum regime holds promises for quantum information processing. Here, we present an electromechanical system capable of operating in the GHz-frequency band in a silicon-on-insulator…
Heat transport by acoustic phonons in 2D materials is fundamentally different from that in 3D crystals because the out-of-plane phonons propagate in a unique way that strongly depends on tension and bending rigidity. Since in-plane and…
At micro- to nano-scales, classical size effects in heat conduction play an important role in suppressing the thermal transport process. Such effects occur when the characteristic lengths become commensurate to the mean free paths (MFPs) of…
We optomechanically measure the vibrations of a nanomechanical system made of a graphene membrane suspended on a silicon nitride nanoresonator. When probing the thermal noise of the coupled nanomechanical device, we observe a significant…
Optical measurements of a nanoscale silicon optomechanical crystal cavity with a mechanical resonance frequency of 3.6GHz are performed at sub-kelvin temperatures. We infer optical-absorption-induced heating and damping of the mechanical…
Acoustic devices play an important role in classical information processing. The slower speed and lower losses of mechanical waves enable compact and efficient elements for delaying, filtering, and storing of electric signals at radio and…
The study of thermal transport in low-dimensional materials has attracted a lot of attention recently after discovery of high thermal conductivity of graphene. Here we study numerically phonon transport in low-dimensional carbon structures…
We investigate the vibrational, optical, and electronic properties of insulating YbN thin films using Raman spectroscopy, Fourier-transform infrared spectroscopy, and electrical transport measurements, supported by density functional…
Advancing electromechanical resonators towards terahertz frequencies opens vast bandwidths for phononic signal processing. In quantum phononics, mechanical resonators at these frequencies can remain in their quantum ground state even at…
The features of phonon spectra and their effect on the vibrational heat capacity of linear chains of inert gas atoms adsorbed onto a substrate, which is the surface of nanotubes bound to a nanobundle. The influence of the substrate results…
We study the effect of confinement on the phonon properties of ultra-narrow silicon nanowires of side sizes of 1-10nm . We use the modified valence force field method to compute the phononic dispersion, and extract the density of states,…
High-harmonic generation in solids has emerged as a powerful probe of ultrafast electron dynamics and lattice motion, and recent theoretical work has suggested that thermally driven lattice fluctuations can act as an effective source of…
Nonequilibrium phonon transport driven by nanoscale hotspot heating in silicon device layers governs heat dissipation in advanced microelectronics and underscores the need for a better microscopic understanding of such processes. Yet the…
This thesis studies the interaction between near-infrared light and gigahertz sound in nanoscale silicon waveguides. Chapter 2 introduces photon-phonon coupling and its theoretical description, describing basic mechanisms and developing a…
In real-time quantum feedback protocols, the record of a continuous measurement is used to stabilize a desired quantum state. Recent years have seen highly successful applications in a variety of well-isolated micro-systems, including…
Thermal phonons are a major source of decoherence in quantum mechanical systems. Operating in the quantum ground state is therefore often an experimental prerequisite. Additionally to passive cooling in a cryogenic environment, active laser…
It appears feasible with nanostructures to perform calorimetry at the level of individual thermal phonons. Here I outline an approach employing monocrystalline mesoscopic insulators, which can now be patterned from semiconductor…