Fermi surface of γ-tin studied by positron 2D-ACAR
Abstract
We present the electrondashposition momentum distribution measured in single crystals of γ-tin (Sn 0.8 In 0.2) by 2D angular correlation of positron annihilation radiation. The Fermi sphere and its Umklapp components up to the 3rd order are easily distinguishable. The deviation of the Fermi surface from a sphere is studied in detail, and compares nicely with theory based on Linear Muffin Tin Orbital band structure calculations. The measured Fermi momentum is estimated to be 1.63 ± 0.01 Å-1 along (1 0 0) (Γ-M), 1.60 ± 0.01 Å-1 along (1 1 0) (Γ-K), and 1.62 ± 0.01 Å-1 along (0 0 1) (Γ-A), close to the calculated values. Compared to neutron scattering results, these values are 3-5% larger. This deviation may find its origin in the different nature of these two experimental techniques.
- Publication:
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Physica B Condensed Matter
- Pub Date:
- May 1996
- DOI:
- 10.1016/0921-4526(96)00017-8
- Bibcode:
- 1996PhyB..222...31H