Single crystal growth by the traveling solvent technique: A review

TL;DR

This review explains the traveling solvent technique for crystal growth, highlighting its principles, experimental variables, and advantages over traditional methods, including successful optical heating applications for specific crystals.

Contribution

It provides a systematic overview of the traveling solvent technique, detailing experimental controls and comparing it with other methods, with new reports on optical heating for certain crystals.

Findings

Successful crystal growth of Tl5Te3, Cd3As2, and FeSc2S4 using optical heating.

Guidelines for controlling growth variables to optimize crystal quality.

Comparison showing advantages over conventional stationary flux methods.

Abstract

A description is given of the traveling solvent technique, which has been used for the crystal growth of both congruently and incongruently melting materials of many classes of intermetallic, chalcogenide, semiconductor and oxide materials. The use of a solvent, growth at lower temperatures and the zoning process, that are inherent ingredients of the method, can help to grow large, high structural quality, high purity crystals. In order to optimize this process, careful control of the various growth variables is imperative; however, this can be difficult to achieve due to the large number of independent experimental parameters that can be grouped under the broad headings growth conditions, characteristics of the material being grown, and experimental configuration, setup and design.This review attempts to describe the principles behind the traveling solvent technique and the various experimental variables. Guidelines are detailed to provide the information necessary to allow closer control of the crystal growth process through a systematic approach. Comparison is made between the traveling solvent technique and other crystal growth methods, in particular the more conventional stationary flux method. The use of optical heating is described in detail and successful traveling solvent growth by optical heating is reported for the first time for crystals of $Tl_5Te_3$, $Cd_3As_2$, and $FeSc_2S_4$ (using Te, Cd and FeS fluxes, respectively).