Far-infrared reflectivity studies on the polycrystalline intermetallic compound MgB2 with a superconducting transition temperature Tc = 39 K were performed at temperatures 20 K to 300 K. We observe a significant raise of the superconductmg-to-normal state reflectivity ratio below 70 cm-1, with a maximum at about 25-30 cm-1, which gives a lower estimate of the superconducting gap of 2Δ(0)≈ 3-4 meV.
- 74.25.Gz Optical properties
- 74.70.Ad Metals; alloys and binary compounds (including A15, Laves phases, etc.)
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics