EECS500 Fall 2017 Department Colloquium

Xian Zhang
Thermal Transport in Novel 2D Materials
SUNY - Buffalo
White 411
11:30 AM - 12:30 PM
December 7, 2017

Following the interest in graphene since its first isolation by mechanical exfoliation 1 decade ago, the broader family of two-dimensional (2D) materials has become the subject of extensive attention thanks to their unique properties and atomically thin structure. In particular, the TMDC materials have shown unique optical and electrical properties, such as band structure transitions, semiconducting transport behavior, and strong photoluminescence, which are distinct from those of graphene and other carbon allotropes. TMDC materials are also intriguing for optical, electrical and thermal applications, especially in few-layer forms. This talk will present the recent progress made towards understanding thermal transport in 2D materials both experimentally and theoretically. Then the talk will focus on the speaker’s systematic experimental results using the state-of-the-art optothermal Raman technique which enables comparisons of experimental results between different layer numbers, different materials, and also different material conditions (suspended vs supported), and the thermal transport phenomena in h-BN encapsulated nano-structure. In the present effort and process of achieving high-quality 2D FETs, low thermal conductance between 2D materials and substrate is regarded as one of the major limitations. Utilizing the refined optothermal Raman technique, interfacial thermal conductance in MoS2 and h-BN, as well as lateral thermal conductivity in BN/MoS2/BN interface are studied. It has been found that the fully BN encapsulated structure offers a great heat dissipation for MoS2. This work not only opens new opportunities for studying thermal transport mechanism in 2D heterostructure devices, but sheds light on engineering high-performance 2D FETs with low energy dissipation, providing important parameters for understanding heat dissipation in electronic devices.


Dr. Xian (Annie) Zhang received her B.S. in Mechanical Engineering from Shanghai Jiao Tong University, and her M.S. and Ph.D. in Mechanical Engineering from Columbia University. She is currently an assistant professor at SUNY - Buffalo. Her work has been published in leading scientific journals such as Nature, and presented in top international conferences. Dr. Zhang’s research interest includes energy transport in nano-materials, nano-fabrication, and bio-applications of mechanical nano-devices.