Electronic transport in lightly doped CoSb{sub 3}
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
We report resistivity, Hall coefficient, and Seebeck coefficient measurements on a very lightly doped (1/{ital R}{sub {ital H}}{ital e}=7.0{times}10{sup 16} holes/cm{sup 3}) single crystal of CoSb{sub 3}. The low-temperature resistivity is semiconducting, with a gap {ital E}{sub {ital g}}=580 K ({approx}50 meV). At high temperatures another energy scale is apparent, with a characteristic energy {ital E}{sub {ital g}}=3650 K ({approx}0.31 eV). The presence of two energies is consistent with a recent band-structure calculation performed by Singh and Pickett. The Hall coefficient is large and positive, as expected for a lightly doped {ital p}-type semiconductor. Below 200 K, the Hall mobility {ital R}{sub {ital H}}{sigma} varies as {ital T}{sup 3/2}, indicating that ionized impurity scattering is the dominant scattering mechanism. The Hall mobility peaks at 250 K at a value of 1940 cm{sup 2} V{sup {minus}1} sec{sup {minus}1}. The Seebeck coefficient is small at low temperature, and increases smoothly until it attains a value of 225 {mu}V/K at 300 K; its temperature dependence is also consistent with ionized impurity scattering. A detailed structural refinement on our crystals gives a lattice parameter of 9.035 73(3) A, with evidence for little or no site disorder.
- OSTI ID:
- 90524
- Journal Information:
- Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 7 Vol. 52; ISSN PRBMDO; ISSN 0163-1829
- Country of Publication:
- United States
- Language:
- English
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