Nitrides Seminar - Dr. Sai Mu (postdoc)

2/7/2022 12:00PM ESB 1001 and via Zoom

First-principles studies of novel nitrides: ScN, YN and LaN

Sai Mu, Postdoctoral Researcher, Van de Walle's Group

In-person at ESB 1001 or 

Join Zoom Meeting

Meeting ID: 846 7258 1534
Passcode: 983449


Sai Mu, Andrew Rowberg, Haochen Wang, Nicholas Adamski, Chris G. Van de Walle

Materials Department, University of California, Santa Barbara, California, USA

Conventional nitride semiconductors, such as GaN, AlN, InN and their alloys, are key materials for LED, lasers, power electronics and high-electron-mobility transistors. Interest in other novel nitrides, such as ScN, LaN, YN, has recently surged due to their unique functionalities, adding them to the technologically important III-nitride compounds. We use first principles calculations to understand the unique functionalities of ScN, LaN, YN and to reveal the underlying physics behind them. Rocksalt ScN has attracted great attention for its excellent electronic properties and its ability to enhance both ferroelectricity and piezoelectricity of AlN through alloying. In the first part, I will address the electronic properties of ScN and the role of electron-phonon interaction in electron transport [1]. I will also discuss the enhanced ferroelectricity and piezoelectricity of ScAlN random solid solution alloys [2] and the induced giant polarization discontinuity at the interface of ScN/GaN heterojunctions [3]. In the next part, I will discuss the phase stability of novel YN and LaN, and their potential applications as ferroelectrics

[4]. The results provide in-depth understanding of the unique properties of novel nitrides and highlight their potential applications in electronic and ferroelectric devices.

[1] S. Mu, A. Rowberg, J. Leveillee, F. Giustino, C. G Van de Walle, Phys. Rev. B, 104, 075118 (2021).

[2] H. Wang, N. Adamski, S. Mu, C. G. Van de Walle, J. Appl. Phys, 130, 104101 (2021). [Editor’s pick]

[3] N. L. Adamski, C. E. Dreyer, C. G. Van de Walle, Appl. Phys. Lett. 115, 232103 (2019).

[4] A.J.E. Rowberg, S. Mu, M. W. Swift, C. G. Van de Walle, Phys. Rev. Mater. 5, 094602 (2021).