Growth of CuMnAs by molecular beam epitaxy: Control over structure and properties

Antiferromagnetic materials have recently attracted significant attention in connection with the discovery of a way to electrically manipulate their magnetic ordering [1]. Especially magnetic reorientation of tetragonal CuMnAs layers by electrical current has potential for future industrial applications of antiferromagnetic memories [2]. We will present a detailed strategy for growth of CuMnAs by molecular beam epitaxy, while focusing on crystallinity of the grown thin films. These typically contain different densities of specific structural defects, which likely influence their electrical and magnetic properties. This, together with ageing in ambient conditions and siginificant surface roughness complicates practical implementations of CuMnAs thin films. We will show how careful tuning of the growth conditions improves the structural properties of the material and how growth parameters are reflected in conductivity, Hall coefficient and effectivity of Néel vector manipulation.

[1] T. Jungwirth, X. Marti, P. Wadley, and J. Wunderlich, Nat. Nanotech. 11, 231-241 (2016)
[2] P. Wadley, B. Howells, J. Zelezný, et al., Science 351, 587-590 (2016)