相关论文: Symmetry Hierarchy and Thermalization Frustration …
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…
We consider losses in monolayer graphene nanoresonator connected with Joule dissipation (heating) caused by valley currents stipulated by synthetic electric fields . These synthetic electric fields arise in graphene membrane due to periodic…
Thermalization in nonlinear systems is a central concept in statistical mechanics and has been extensively studied theoretically since the seminal work of Fermi, Pasta and Ulam (FPU). Using molecular dynamics and continuum modeling of a…
High-stress silicon nitride nanostrings are a promising system for sensing applications because of their ultra-high mechanical quality factors (Qs). By performing thermomechanical calibration across multiple vibrational modes, we are able…
Different damping mechanisms in graphene nanoresonators are studied: charges in the substrate, ohmic losses in the substrate and the graphene sheet, breaking and healing of surface bonds (Velcro effect), two level systems, attachment…
When two solids at different temperatures are separated by a vacuum gap they relax toward their equilibrium state by exchanging heat either by radiation, phonon or electron tunneling, depending on their separation distance and on the nature…
Conversion of electric current into heat involves microscopic processes that operate on nanometer length-scales and release minute amounts of power. While central to our understanding of the electrical properties of materials, individual…
Energy-efficient switching of nanoscale magnets requires the application of a time-varying magnetic field characterized by microwave frequency. At finite temperatures, even weak thermal fluctuations create perturbations in the magnetization…
We theoretically analyse the dynamics of a suspended graphene membrane which is in tunnel contact with grounded metallic electrodes and subjected to ac-electrostatic potential induced by a gate electrode. It is shown that for such system…
New losses mechanism in monolayer graphene nanoresonators caused by dissipative intravalley currents stipulated by the synthetic electric fields is considered. These fields are generated by time-dependent gauge fields arising in graphene…
Surface tension of small grains and droplets makes them stable only at a much lower temperature than in bulk. This makes spontaneous nucleation unfavorable in many cases. Kinetic approaches are delicate in that one can easily generate…
Thermal rectification in thickness asymmetric graphene nanoribbons connecting single-layer with multi-layer graphene is investigated by using classical nonequilibrium molecular dynamics. It is reported that the graphene nanoribbons with…
We examine an intrinsic graphene connected to the phonon thermostat at temperature T under irradiation of thermal photons with temperature T_r, other than T. The distribution of nonequilibrium electron-hole pairs was obtained for the cases…
We discuss the non-radiative heat transfer in non-equilibrium double layer graphene system. We show that at the neutrality point the heat exchange is dominated by the inter-layer plasmon modes and derive analytic expressions for the heat…
The abrupt loss of mechanical stability of two-dimensional graphene-type crystals at a certain transition temperature is described. At this temperature, the graphene state with practically zero-speed bending sound and developed bending…
The damping rates of high quality factor nanomechanical resonators are well beyond intrinsic limits. Here, we explore the underlying microscopic loss mechanisms by investigating the temperature-dependent damping of the fundamental and third…
Current understanding of thermal rectification asserts that the rectification ratio (R), which measures the relative heat flux between two ends of a nanostructure, is determined by its geometric asymmetry. The higher the asymmetry, the…
In self-assembling systems, geometric frustration leads to complex states characterized by internal gradients of shape misfit. Frustrated assemblies have drawn recent interest due to the unique possibility that their thermodynamics can…
The small mass and high coherence of nanomechanical resonators render them the ultimate force probe, with applications ranging from biosensing and magnetic resonance force microscopy, to quantum optomechanics. A notorious challenge in these…
Self-heating is a severe problem for high-power microelectronic devices. Graphene and few-layer graphene have attracted tremendous attention for heat removal thanks to their extraordinarily high in-plane thermal conductivity. However, this…