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TbFe2Ge2 Crystal
Tetragonal Plate

Grown by dissolving the starting elements in Sn flux at ~1200°C, then slowly cooling down to 500-800°C. This material has a tetragonal structure and crystals grow as thin plates with very smooth surfaces. Iron is non-magnetic in the RFe2Ge2 series and most rare earths order antiferromagnetically, showing extreme magnetic anisotropy.

LuFe6Ge6 Crystal
Hexagonal Plates

Grown by dissolving the starting elements in Sn flux at ~1200°C, then slowly cooling down to 500-800°C. This material has a hexagonal structure and crystals grow as thick hexagonal plates with very smooth surfaces. The iron sublattice is known to order antiferromagnetically at ~150°C, but the rare earth sublattices in the RFe6Ge6 series are not affected by this ordering and behave independently.

Ho-Mg-Zn Quasicrystal
Icosahedral Morphology

Grown by using the self-flux method (excess Mg), and slowly cooling from 700°C to 480°C, the R-Mg-Zn family is the first rare-earth containing quasicrystal structure, which allows the study of localized magnetic moments in a quasiperiodic environment.

Al-Ni-Co Quasicrystal
Decagonal Bar Morphology

The flux growth technique appears to be a powerful and versatile tool to prepare most of the known quasicrystal systems. The single-grain samples resulting from such growths are large, very well-ordered, strain-free, and show no evidence of secondary phases.

FeSi Single Crystal
Polyhedral Morphology

Grown by dissolving arc-melted FeSi pieces in Sb or Sn flux at ~1200°C, then slowly cooling down to ~700°C. This material has a simple cubic structure and crystals grow as polyhedra or long bars. FeSi is a narrow-gap semiconductor, with a high density of states above and below the Fermi surface.

FeSi Single Crystal
Long Bar Morphology

Grown by dissolving arc-melted FeSi pieces in Sb or Sn flux at ~1200°C, then slowly cooling down to ~700°C. Small thermal gradients in the flux growth environment sometimes favors faster growths in a given crystallographic direction - [111] in the case of FeSi.

ZrNiSn Single Crystal
Polyhedral Morphology

Grown by using the self-flux method (excess Sn), this half-Heusler compound, whose structure can be respresented as 4 interpenetrating cubic fcc sublattices, is part of a series of narrow-gap semiconductors with potential low and intermediate temperature thermoelectric applications.

GdCo2Ge2 Crystal
Tetragonal Lattice

Grown by dissolving rare earth pieces in arc-melted CoGe flux at ~1250°C, then slowly cooling down to ~1100°C. This material has a tetragonal structure and crystals grow as tetragonal plates. Most members of the RCo2Ge2 series are antiferromagnetic with moderately high Neél temperatures and strong magnetic anisotropy.

CrSiTe3 Single Crystal
Hexagonal layered plates.

Grown by using the self-flux method (excess Te), and slowly cooling from 900°C to 500°C. It is an insulating ferromagnet. It has layered structure with a week van der Waals bonding between layers. Thus, it is easily exfoliating even with tape.

CrGeTe3 Single Crystal
Hexagonal layered plates.

Grown by using the self-flux method (excess Te), and slowly cooling from 900°C to 500°C. It is an insulating ferromagnet. It has layered structure with a week van der Waals bonding between layers. Thus, it is easily exfoliating even with tape.

WTe2 Single Crystal
Layered Morphology

Grown by using the self-flux method (excess Te), and slowly cooling from 1000°C to 460°C. It is type II Weyl semimetal, and it shows extremely large magnetoresistance at low temperatures.

CaKFe4As4 Crystal
Tetragonal Lattice

This large crystal of superconducting CaKFe4As4 were grown from an Fe-As rich solution between 1050°C and 930°C. This stoichiometric member of the Fe-based superconductors has a Tc of 35 K and forms a dashing hat President Lincoln.

 
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Last Update: January 22, 2011 by S.L.Bud'ko