Related papers: Strong phase correlation between diffusons governs…
Normal mode decomposition of atomic vibrations has been used to provide microscopic under-standing of thermal transport in amorphous solids for decades. In normal mode methods, it is naturally assumed that atoms vibrate around their…
Thermal atomic vibrations in amorphous solids can be distinguished by whether they propagate as elastic waves or do not propagate due to lack of atomic periodicity. In a-Si, prior works concluded that non-propagating waves are the dominant…
While there are several methods, e.g., anharmonic lattice dynamics and normal mode decomposition, to compute the modal lattice vibrational information in perfect crystals, the modal information of vibrations, e.g., vibrational relaxation…
The thermal properties of amorphous materials have attracted significant attention due to their technological importance in electronic devices. Additionally, the disorder-induced breakdown of the phonon gas model makes vibrational transport…
Thermal conductivity is an important property for almost all applications involving heat transfer, ranging from energy and microelectronics to food processing and textiles. The theory and modeling of crystalline materials is in some sense a…
Thermal transport properties of amorphous carbon has attracted increasing attention due to its extreme thermal properties: It has been reported to have among the highest thermal conductivity for bulk amorphous solids up to $\sim$ 37…
Amorphous silica (a-SiO$_2$) is a foundational disordered material for which the thermal transport properties are important for various applications. To accurately model the interatomic interactions in classical molecular dynamics (MD)…
Heat transfer at the interface between two materials is becoming increasingly important as the size of electronic devices shrinks. Most studies concentrate on the interfacial thermal conductance between either crystalline-crystalline or…
Thermal transport in solids changes its nature from phonon propagation that suffers from perturbative scattering to thermally activated hops between localized vibrational modes as the level of disorder increases. Models have been proposed…
Using direct atomic simulations, the vibration scattering time scales are characterized, and then the nature and the quantitative weight of thermal excitations are investigated in an example system Li2S from its amorphous solid state to its…
Hydrogenated amorphous silicon (a-Si:H) has garnered considerable attention in the semiconductor industry, particularly for its use in solar cells and passivation layers for high performance silicon solar cells, owing to its exceptional…
Proper consideration of anharmonicity is important for the calculation of the thermal conductivity. However, how the anharmonicity influences the thermal conduction in amorphous materials is still an open question. In this work, we uncover…
Traditional theories of interfacial heat transfer by atomic vibrations, also known as phonons, do not explain how vibrational mode interactions contribute to interface conductance. Traditional methods also use the concept of phonons as…
The effect on the vibrational and thermal properties of gradually interconnected nanoinclusions embedded in an amorphous silicon matrix is studied using MD simulations. The nanoinclusion arrangement ranges from an aligned sphere array to an…
Amorphous alumina is employed ubiquitously as a high-dielectric-constant material in electronics, and its thermal-transport properties are of key relevance for heat management in electronic chips and devices. Experiments show that the…
Numerical studies of amorphous silicon show that the lowest 4% of vibrational modes are plane-wave like ("propagons") and the highest 3% of modes are localized ("locons"). The rest are neither plane-wave like nor localized. We call them…
This paper studies thermal transport in nanoporous silicon with a significant specific surface area. First, the equilibrium molecular dynamics approach was used to obtain the dependence of thermal conductivity on a specific surface area.…
Amorphous materials are also distinguished from crystals by their thermal properties. The structural disorder seems to be responsible both for a significant increase in heat capacity compared to crystals of the same composition, but also…
Interfaces play an essential role in phonon-mediated heat conduction in solids, impacting applications ranging from thermoelectric waste heat recovery to heat dissipation in electronics. From the microscopic perspective, interfacial phonon…
Understanding the transport mechanism of electronic excitations in conjugated polymers is key to advancing organic optoelectronic applications, such as solar cells, OLEDs and flexible electronics. While crystalline polymers can be studied…