High-pressure growth and characterization of bulk MnAs single crystals

TL;DR

This study reports the high-pressure growth of bulk MnAs single crystals, their structural and magnetic characterization, and discusses potential for future research on related materials.

Contribution

First successful growth of large MnAs single crystals using high-pressure techniques, enabling further exploration of its properties and analogues.

Findings

Crystals exhibit a hexagonal structure confirmed by X-ray diffraction.

Magnetization measurements show a first-order transition at 318.5 K.

Crystals have a plate-like morphology with dimensions up to 3 x 2 x 0.5 mm.

Abstract

Bulk single crystals of manganese arsenide (MnAs) were grown from melt at 1 GPa and 1100 {\deg}C by using a cubic-anvil, high-pressure, and high-temperature technique. The as-grown black colored crystals extracted from solidified lump exhibit a plate-like morphology, with flat surfaces and maximum dimensions up to ~ 3 x 2 x 0.5 mm3. The hexagonal crystal structure at room temperature was confirmed by X-ray diffraction [B81, space group P63/mmc, No 194, Z = 2, a = 3.7173(4) {\AA}, b = 3.7173(4) {\AA}, c = 5.7054(8) {\AA}, and V = 68.277(16) {\AA}3]. Temperature-dependent magnetization measurements reveal the occurrence of a first-order ferro- to paramagnetic transition at Tc = 318.5 K accompanied by a hysteresis of ~ 9 K. The successful growth of relatively large crystals reported here might be extended to various substituted analogues of MnAs, thus opening new possibilities for further exploration of this interesting system.