Programme

P.31 -- Poster, VCTP-49

Date: Wednesday, 31 July 2024

Time: 08:30 - 10:00

Thermoelectric and magnetic properties of bismuth telluride with a Gd point defect

Tran Van Quang (1), and Miyoung Kim (2)

(1) Faculty of Electronics and Telecommunications, VNU University of Engineering and Technology, Hanoi 100000, Viet Nam; (2) Department of Applied Physics, Sookmyung Women’s University, Seoul 04310, Republic of Korea

Rare earth-doped Bi2Te3 reveals many exotic magnetic properties promising for functional-material applications such as thermoelectricity and spintronics. In this work, we carried out first-principles electronic structure calculation within the density functional theory to examine the magnetic and thermoelectric properties of the bismuth telluride with a Gd point defect. The newly formed compound Gd1/3Bi5/3Te3, composed of a Te-Gd-Te-Bi-Te layer sandwiched between two quintuple layers, is ferromagnetic with a magnetic moment of 7.0 µB. This value originates from the f-states of Gd inside the layer. The Te-Gd-Te-Bi-Te layer leads to the semimetallic behavior of the compound. The feature enhances the bipolar conduction effect, reducing the power factor. Optimizing the carrier concentration and keeping temperatures low are methods to improve the thermoelectric performance of Gd1/3Bi5/3Te3

Presenter: Tran Van Quang