Related papers: Reduction of Self-heating effect in LDMOS devices
Self-heating effects can significantly degrade the performance in nanoscale devices. We investigate self-heating effects in such devices based on two-dimensional materials using ab-initio techniques. A new algorithm was developed to allow…
Recent studies reveal that four-phonon scattering is generally important in determining thermal conductivities of solids. However, these studies have been focused on materials where thermal conductivity $\kappa$ is dominated by acoustic…
It has been proposed for a long time now that the reduction of the thermal conductivity by reducing the phonon mean free path is one of the best way to improve the current performance of thermoelectrics. By measuring the thermal conductance…
The mechanisms causing the reduction in lattice thermal conductivity in highly P- and B-doped Si are looked into in detail. Scattering rates of phonons by point defects, as well as by electrons, are calculated from first principles. Lattice…
The cooling of two-dimensional electrons in silicon-metal-oxide semiconductor field effect transistors is studied experimentally. Cooling to the lattice is found to be more effective than expected from the bulk electron-phonon coupling in…
Through advanced quantum mechanical simulations combining electron and phonon transport from first-principles self-heating effects are investigated in n-type transistors with a single-layer MoS2, WS2, and black phosphorus as channel…
This work presents a self-heating study of a 40-nm bulk-CMOS technology in the ambient temperature range from 300 K down to 4.2 K. A custom test chip was designed and fabricated for measuring both the temperature rise in the MOSFET channel…
The thermal conductivity of a freestanding single-crystal silicon membrane may be reduced significantly by attaching nanoscale pillars on one or both surfaces. Atomic resonances of the nanopillars locally and intrinsically couple with the…
We compute the transient dynamics of phonons in contact with high energy "hot" charge carriers in 12 polar and non-polar semiconductors, using a first-principles Boltzmann transport framework. For most materials, we find that the decay in…
The impact of lattice type, period, porosity and thickness of two-dimensional silicon phononic crystals on the reduction of thermal conductance by coherent modification of phonon dispersion is investigated using the theory of elasticity and…
The lattice thermal conductivity ($\kappa$) of two ceramic materials, cerium dioxide (CeO$_2$) and magnesium oxide (MgO), is computed up to 1500 K using first principles and the phonon Boltzmann Transport Equation (PBTE) and compared to…
We present a machine-learning interatomic potential (MLIP) framework, which substantially accelerates the prediction of lattice thermal conductivity for both particle-like and wave-like thermal transport, including three-phonon and…
We show that the anomalous decrease in the thermal conductivity of cuprates below 300 mK, as has been observed recently in several cuprate materials including Pr$_{2-x}$Ce$_x$CuO$_{7-\delta}$ in the field-induced normal state, is due to the…
The thermal conductivity of several diamond-like materials is calculated from a kinetic-collective model. From this approach, a thermal conductivity expression is obtained that includes a transition from a kinetic (free) to a collective…
Isotope effects on heat conduction and convection have been known for decades. However, whether thermal radiation can be isotopically engineered remains an open question. Here, we predict over 3-orders-of-magnitude variation of radiative…
Thermal transport in single layer molybdenum disulfide (MoS2) is critical to advancing its applications. In this paper, we use molecular dynamics (MD) simulations with first-principles force constants to study the isotope effect on the…
Declining the lattice thermal conductivity in graphene is essential for its thermoelectric applications. In high electron density systems, scatterings of phonons by electrons are no less than the phonon scatterings by other phonons. With…
In semiconductors almost all heat is conducted by phonons (lattice vibrations), which is limited by their quasi-particle lifetimes. Phonon-phonon interactions represent scattering mechanisms that produce thermal resistance. In…
Electron heating in an ultracold neutral plasma is modeled using classical molecular dynamics simulations in the presence of an externally applied magnetic field. A sufficiently strong magnetic field is found to reduce disorder induced…
Effects of resonant acoustic phonon scattering on magnetoresistivity are examined in two-dimensional electron systems at low temperatures by using a balance-equation magnetotransport scheme direct controlled by the current. The…