Anomalous thermoelectricity in strained Bi2Te3 films

作者：Liu, Yucong; Chen, Jiadong; Deng, Huiyong^*; Hu, Gujin; Zhu, Daming; Dai, Ning^*

来源：Scientific Reports, 2016, 6(1): 32661.

DOI：10.1038/srep32661

• BISMUTH TELLURIDE
• ELECTRICAL-RESISTIVITY
• PIEZOELECTRICITY
• POWER
• PERFORMANCE
• GROWTH

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.

• 出版日期2016-9-7
• 单位中国科学院上海技术物理研究所; 中国科学院大学