题目：Anomalous phonon/heattransport in low dimensional micro/nano systems
报告人：Baowen Li Departmentof Mechanical Engineering, University of Colorado
地点： 教十二―201
时间： 5月28日，周二，15:00-16:00
Abstract：
Whensystem dimension and size go down, many interesting phenomena can happen. Bothexperimental and numerical works in recent years have shown that phonon/heattransport in low (quasi 1D and 2D) dimensional micro systems and nanostructures like nanotube, nanowire, polymer chain, graphene, and other 2Dmaterials show anomalous behavior:
(a)heat conduction due to phonons does not follow the Fourier law;
(b)heat transports may break down the reciprocal principle, namely heat flowsasymmetrically.
(c)negative differential thermal resistance will arise, namely the larger thetemperature drops, the smaller the heat current.
Issues(b) and (c) can be used to build up useful phononic thermal devices like thermaldiode and thermal transistor, which lay the foundation of a new emerging field� phononics.
Inthis talk, I will discuss the underlying physical mechanism of these anomalousheat/phonon transport. In particular, I will discuss how the anomalous thermaltransport - a macroscopic phenomenon � is connected with the anomalous energydiffusion - a microscopic process.
References:
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X. K Gu, et al, Rev.Mod. Phys 90 (4), 041002 (2018)
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X-F Xu et al, NatComm 10, 1038 (2014).
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S Liu et al, PhysRev. Lett 112, 040601 (2014).
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N-B Li et al, Rev ModPhys 84 (3), 1045 (2012).
Bio about the speaker:
Dr. Li received B. S fromNanjing University, M. Sci from Institute of Acoustics, the Chinese Academy ofScience, and Ph. D from Oldenburg University, Germany in 1985, 1989 and 1992,respectively. He joined National University of Singapore (NUS) as assistantprofessor in 2000, and become full professor in 2007 and worked there until2014. He has been 2014/2015 Russell Severance Springer Professor at Departmentof Mechanical Engineering, UC Berkeley. In August 2015, he joined Department Mechanical Engineering, Universityof Colorado Boulder as the Rennie Family Endowed Professor.
He is one of the pioneers inan emerging field � Phononics. He has authored and co-authored over 330 papersincluding 2 in Rev. Mod. Phys and 30 in Phys Rev. Lett. Delivered more than 220plenary, keynote, invited/seminar talks. He is APS fellow (2013), and recipientof numerous awards including 2005 National Science Award, Singapore, and 2005OCPA’s (International Organization of Chinese Physicists and Astronomers) AsiaAchievement Award and 2014/2015 Springer Professorship at University ofCalifornia, Berkeley. 2017 Brillouin Medal from International PhononicsSociety. He is selected member of Academy of Europaea since 2017.
His currently researchactivities include but not limited to: fundamental theory and measuringtechniques of phonon/heat transport, phononic thermal devices, thermalmetamaterials, topological and quantum phononics, quantum sensors, and complexnetworks etc.
欢迎老师和同学参加！
