2:30 PM - NM08.03.07
Late News: Linearized Peierls Boltzmann Transport Solution of Heat Accumulation at Interfaces
Abhishek Pathak1,Avinash Pawnday2,Aditya Roy2,Amjad Aref1,Gary Dargush1,Dipanshu Bansal2
University at Buffalo, The State University of New York1,Indian Institute of Technology Bombay2
Interfaces impede phonon transmission and cause heat accumulation. This heat accumulation degrades the performance of nanoscale transistors and microprocessor chips used in our everyday life. Hence effective thermal management strategies are desirable to control the heat carriers both at an atomic scale and at the device level. Several phenomenological elastic phonon transmission models, such as the acoustic mismatch model, diffuse mismatch model, atomistic Green's function, are proposed to spectrally resolve the phonon conductance across the interface1. More recently, the conductance is shown to have a significant (~50%) contribution from inelastic phonon transmission assisted by interfacial modes2. Moreover, within both elastic and inelastic phonon transmission, phonons can retain or lose their coherency3. Simulation of these elastic and inelastic models at the device level is necessary to design effective thermal management strategies.
To this end, we have developed a variance-reduced Monte Carlo solver for linearized Peierls Boltzmann transport equation in three-dimensions4. Using phonon dispersions and lifetime from inelastic scattering experiments, ab-initio simulations, or empirical models, we simulate domains ranging from a few nanometers to hundreds of microns. Simulations are performed on both periodic and non-periodic geometries. Since phonons scatter differently from physical domain boundaries, interface, impurity, and other phonons, we simulate boundary scattering, three-phonon processes, two-phonon processes, and impurity scattering independently. A frequency-dependent transmission probability and interface roughness (specularity) capture the size-effects and device-level conditions. Grain-boundary scattering models and interface transmission models are incorporated separately. Our interface modeling strategy is not limited to elastic energy transport and allows us to include inelastic transport across the interface by energy exchange between high- and low-frequency modes. We compare our interface conductance results in quasi-ballistic and diffusive regimes measured using near-IR pump EUV/X-ray probe experiments5,6,7. The spectrally-resolved contribution to temperature and flux at the interface provides critical insights into the heat accumulation. We are presently simulating interfacial conductance in layered materials to compare with available near-IR pump and X-ray probe experiments8. We anticipate our code will further find applications in evaluating the nano-structuring and nano-patterning efficiency to thermal conduction properties of mesoscale devices.
1. Monachon, C., Weber, L., & Dames, C. (2016), Annual Review of Materials Research, 46, 433–463.
2. Feng, T., Zhong, Y., Shi, J., & Ruan, X. (2019). Physical Review B, 99(4), 045301.
3. Ravichandran, N. K., & Minnich, A. J. (2014). Physical Review B, 89(20), 205432.
4. MCBTE-v0.1. Nov. 2020. https://github.com/abhipath90/MCBTE
5. Siemens, M. E., Li, Q., Yang, R., Nelson, K. A., Anderson, E. H., Murnane, M. M., & Kapteyn, H. C. (2010). Nature Materials, 9(1), 26–30.
6. Hoogeboom-Pot, K. M., Hernandez-Charpak, J. N., Gu, X., Frazer, T. D., Anderson, E. H., Chao, W., Falcone, R. W., Yang, R., Murnane, M. M., Kapteyn, H. C., & Nardi, D. (2015). Proceedings of the National Academy of Sciences of the United States of America, 112(16), 4846–4851.
7. Frazer, T. D., D., Knobloch, J. L., Hoogeboom-Pot, K. M., Nardi, D., Chao, W., Falcone, R. W., Murnane, M. M., Kapteyn, H. C., & Hernandez-Charpak, J. N. (2019). Physical Review Applied, 11(2), 1.
8. Nyby, C., Sood, A., Zalden, P., Gabourie, A.J., Muscher, P., Rhodes, D., Mannebach, E., Corbett, J., Mehta, A., Pop, E. and Heinz, T.F., (2020). Advanced Functional Materials, 30(34), p.2002282.