Efficient thermal management is critical to device performance and reliability for energy conversion,nanoelectronics, and the development of quantum technologies. The commonly-used diffusive modelof heat transport bre...Efficient thermal management is critical to device performance and reliability for energy conversion,nanoelectronics, and the development of quantum technologies. The commonly-used diffusive modelof heat transport breaks down for confined nanoscale geometries, and advanced theories beyonddiffusion are based on disparate assumptions that lead to conflicting predictions. Here, we outline andcontrast the two predominant formulations of the Boltzmann equation for heat transport insemiconductors, namely, the ballistic and hydrodynamic models. We examine these methods in lightof experiments and atomistic calculations of heat fluxes and temperature profiles in phononic systemswith nanometer-sized features. Weargue that reconciling the hydrodynamic and ballistic formulationsis an outstanding necessity to develop a unifying theory of confinement effects on phonon flow, whichwill ultimately lead to optimal strategies for thermal management in nanodevices.展开更多
基金support from the STROBE National Science Foundation Science & Technology Center, Grant No. DMR-1548924A.B. acknowledges support from the Spanish Ministerio de Ciencia, Innovación y Universidades, Grant No. PID2021-122322NB-I00 and TED2021-129612B-C22 (MCIU/AEI/10.13039/501100011033/FEDER UE)+2 种基金the AGAUR - Generalitat de Catalunya, Grant No. 2021-SGR-00644This work utilized the Alpine high performance computing resource at the University of Colorado Boulder. Alpine is jointly funded by the University of Colorado Boulder, the University of Colorado Anschutz, and Colorado State UniversityT.K.S. and I.D. acknowledge primarily support from the Center for Nanoscale Science under Grants No. DMR-1420620 and No. DMR-2011839 [NSF-funded Materials Research Science and Engineering Centers (MRSEC)].
文摘Efficient thermal management is critical to device performance and reliability for energy conversion,nanoelectronics, and the development of quantum technologies. The commonly-used diffusive modelof heat transport breaks down for confined nanoscale geometries, and advanced theories beyonddiffusion are based on disparate assumptions that lead to conflicting predictions. Here, we outline andcontrast the two predominant formulations of the Boltzmann equation for heat transport insemiconductors, namely, the ballistic and hydrodynamic models. We examine these methods in lightof experiments and atomistic calculations of heat fluxes and temperature profiles in phononic systemswith nanometer-sized features. Weargue that reconciling the hydrodynamic and ballistic formulationsis an outstanding necessity to develop a unifying theory of confinement effects on phonon flow, whichwill ultimately lead to optimal strategies for thermal management in nanodevices.
