Anomalous thermoelectricity in strained Bi2Te3 films.
Bi2Te3-based alloys have been intensively used for thermoelectric coolers and generators due to their high Seebeck coefficient S. So far, efforts to improve the S have been made mostly on changing the structures and components. Herein, we demonstrate an anomalous thermoelectricity in strained Bi2Te3 films, i.e., the value of S is obviously changed after reversing the direction of temperature gradient. Further theoretical and experimental analysis shows that it originates from the coupling of thermoelectric and flexoelectric effects caused by a stress gradient. Our finding provides a new avenue to adjust the S of Bi2Te3-based thermoelectric materials through flexoelectric polarization.
National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.|University of Chinese Academy of Science, Beijing 100049, China.
Yucong
Y
Liu
National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.|Changzhou Institute of Optoelectronic Technology, Changzhou 213164, China.
Jiadong
J
Chen
National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
Huiyong
H
Deng
National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.
Gujin
G
Hu
Department of Physics, University of Missouri-Kansas City, Missouri 64110, USA.
Daming
D
Zhu
National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China.|Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou 213164, China.
Ning
N
Dai