X-ray method to study temperature-dependent stripe domains in MnAs/GaAs(001)

TL;DR

This paper introduces an X-ray scattering method to analyze temperature-dependent stripe domains in MnAs/GaAs(001) films, revealing the long-range ordered stripe structure during phase coexistence across a temperature range.

Contribution

It presents a novel X-ray based technique to study surface morphology and stripe domain arrangements during phase transitions in MnAs films.

Findings

Stripe period remains constant during phase coexistence.

Long-range ordered stripe structure observed during transition.

Method confirms previous results with other techniques.

Abstract

MnAs films grown on GaAs (001) exhibit a progressive transition between hexagonal (ferromagnetic) and orthorhombic (paramagnetic) phases at wide temperature range instead of abrupt transition during the first-order phase transition. The coexistence of two phases is favored by the anisotropic strain arising from the constraint on the MnAs films imposed by the substrate. This phase coexistence occurs in ordered arrangement alternating periodic terrace steps. We present here a method to study the surface morphology throughout this transition by means of specular and diffuse scattering of soft x-rays, tuning the photon energy at the Mn 2p resonance. The results show the long-range arrangement of the periodic stripe-like structure during the phase coexistence and its period remains constant, in agreement with previous results using other techniques.