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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.

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