Electronic and Structural Changes in Plastically Deformed Tellurides

PbTe and related tellurides are known for their exceptional thermoelectric properties, and have recently garnered interest for their complex local structure, quantum paraelectricity, and superconductivity. Despite PbTe’s simple rocksalt structure, X-ray and neutron scattering data provide evidence for local asymmetry and fluctuating local dipoles [1] which is not fully understood. Alloyed tellurides also exhibit intriguing behaviors, such as low carrier density superconductivity and topological band structure [2]. These results motivate the exploration of tuning structural and electronic properties of tellurides to bring about complex functionalities. A promising approach is plastic deformation, which has been proven to significantly alter the structural and electronic properties of the similar quantum paraelectric SrTiO3 by enhancing ferroelectric and superconducting fluctuations post-deformation [3]. Here, we examine the effects of room- and low-temperature plastic deformation in tellurides using diffuse X-ray scattering and charge transport measurements. Remarkably, we find that PbTe is highly ductile at room temperature and retains this ductility at temperatures as low as 1.5 K.

[1] K.A. Holm et al., Phys. Rev. B 102, 024112 (2020)

[2] R. Zhong et al., Crystals 7, 55 (2017)

[3] S. Hameed, D. Pelc et al., Nat. Mat. 21, 54 (2022)