Finding the Right Solution
NaAs has been discovered to be an effective solvent for RFeAsO (R = rare earth) superconducting compounds and enables the growth of sizeable high quality single crystals by the solution method at ambient pressure. Solution growth is a versatile, rapid technique for growth of single crystals. Much like preparing rock candy, the technique relies on having the right solution that dissolves and then precipitates the compound of interest. Use of NaAs makes it possible to prepare RFeAsO crystals in a conventional laboratory setting and does not require specialized techniques, such as high pressure cells. Single crystals are critical to unravel the intrinsic and anisotropic physical properties of RFeAsO superconductors. Despite extensive efforts over the past year and a half, the largest RFeAsO single crystals are still in submillimeter size and too small for studies, such as neutron scattering. However, with this newly discovered technique, this is no longer the case. Large single crystals grown from NaAs solvent enable studies using a variety of techniques and comparisons with other superconductors. This growth protocol serves to make RFeAsO crystals available worldwide, leading to an explosion in experimental work and a more complete understanding of iron pnictide superconductors.
- J.-Q. Yan, S. Nandi, J. L. Zarestky, W. Tian, A. Kreyssig, B. Jensen, A. Kracher, K. W. Dennis, R. J. McQueeney, A. I. Goldman, R. W. McCallum, and T. A. Lograsso. "Flux growth at ambient pressure of millimeter-sized single crystals of LaFeAsO, LaFeAsO1-xFx, and LaFe1-xCoxAsO" Applied Physics Letters 95, 222504 (2009)
Contact: Jiaqiang Yan, firstname.lastname@example.org