Self-selecting vapor growth of transition metal halide single crystals

TL;DR

This paper reviews a vapor growth technique called self-selecting vapor transport for producing large, high-quality transition metal halide single crystals, which are essential for studying quantum phenomena.

Contribution

It demonstrates the effectiveness of the self-selecting vapor transport method for growing sizable transition metal halide single crystals, including modifications to improve efficiency.

Findings

Successfully grew large single crystals of RuCl₃, CrCl₃, Ru₁₋ₓCrₓCl₃, and CrBr₃.

Modified the technique by cooling the ampoule to expedite crystal formation.

Showed the potential of this method for quantum material research.

Abstract

Transition metal halides can host a large variety of novel phenomena, such as magnetism in the monolayer limit, quantum spin liquid and spiral spin liquid states, and topological magnons and phonons. Sizeable high quality single crystals are necessary for investigations of magnetic and lattice excitations by, for example, inelastic neutron scattering. In this paper, we review a less well-known vapor transport technique, self-selecting vapor growth, and report our growths of transition metal halides using this technique. We report the growth and characterizations of sizable single crystals of RuCl$_3$, CrCl$_3$, Ru$_{1-x}$Cr$_x$Cl$_3$, and CrBr$_3$. In order to expedite the conversion of starting powder to single crystals, we modified the technique by cooling the growth ampoule through an appropriate temperature range. Our work shows that the self-selecting vapor transport technique can provide large single crystals of transition metal halides, demonstrating its potential for providing high quality single crystals of quantum materials.