Fermi surface and extended van Hove singularity in the non-cuprate layered perovskite superconductor Sr{sub 2}RuO{sub 4}
- Forschungszentrum Karlsruhe (Germany); and others
With high-resolution ({approx}22 meV) angle-resolved photoemission spectroscopy, the Fermi surface of the first copper free layered-perovskite superconductor, Sr{sub 2}RuO{sub 4}, was determined. The authors observed three bands to cross the Fermi energy in qualitative agreement with LDA band structure calculations; one electron-like surface encircling the {bar {Gamma}} point in the projected Brillouin zone, and two hole-like surfaces around the {bar X} point. The most striking aspect of the measurements is the observation of an extended van Hove singularity. It is located 17 meV below the Fermi energy and extends around the {bar M} point for about 0.2 {Angstrom}{sup {minus}1} along both the {bar {Gamma}} - {bar M} - {bar {Gamma}} and the {bar X} - {bar M} - {bar X} directions. These observations demonstrate that van Hove singularities near the Fermi surface are a more generic feature of layered oxides, and call for a clarification of their exact role in oxide superconductivity.
- Sponsoring Organization:
- USDOE
- OSTI ID:
- 443704
- Report Number(s):
- CONF-960808--
- Journal Information:
- Journal of Low Temperature Physics, Journal Name: Journal of Low Temperature Physics Journal Issue: 5-6 Vol. 105; ISSN 0022-2291; ISSN JLTPAC
- Country of Publication:
- United States
- Language:
- English
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