Absorption and photoinduced-absorption spectroscopy in semiconducting YBa sub 2 Cu sub 3 O sub 6+ x

Journal Article · Wed May 01 04:00:00 EDT 1991 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.43.10582· OSTI ID:5689628

Leng, J M; Ginder, J M ^[1]; Farneth, W E; Shah, S I ^[2]; Epstein, A J ^[3]

---

1. Department of Physics, The Ohio State University, Columbus, Ohio 43210-1106 (USA)
2. E. I. du Pont de Nemours and Co., Inc., Central Research and Development Department, Experimental Station, Wilmington, Delaware 19880-0356 (USA)
3. Department of Physics and Department of Chemistry, The Ohio State University, Columbus, Ohio 43210-1106 (USA)

Semiconducting YBa{sub 2}Cu{sub 3}O{sub 6+{ital x}} thin films with {ital x}=0.0 and 0.3 have been studied extensively via direct-absorption (0.2--5.5 eV) and photoinduced-absorption (0.5--3.3 eV) techniques. Optical absorptions at {similar to}0.5, {similar to}1.7, {similar to}3.0, {similar to}4.3, and {similar to}4.8 eV were observed in direct-absorption studies for {ital x}=0.0. With addition of oxygen to form the {ital x}=0.3 composition, these absorptions evolved to {similar to}0.5, {similar to}1.7, {similar to}3.0, {similar to}4.3, and {similar to}5.2 eV. The photoinduced-absorption spectra showed several common features: Two broad photoinduced-absorption bands peaked at 1.1 and 1.4 eV and two strong photoinduced-bleaching peaks at 1.9 and 2.6 eV. The photoinduced-absorption peaks are assigned to optical transitions from O {ital p} bands to a photoinduced charged-defect state. This self-localized positively charged defect state may be direct evidence of the presence of an oxygen 2{ital p} hole {ital polaronic} state in semiconducting YBa{sub 2}Cu{sub 3}O{sub 6+{ital x}} upon photoexcitation. Within this model, the double peaks of photoinduced absorption reflect the excitation spectrum of the Zhang-Rice singlet predicted by Chen and Schuettler for the strong-coupling-limit {ital t}-{ital J} model. Possible alternative origins of the photoinduced-absorption peaks are pointed out. A photoinduced absorption peaked at 0.13 eV and varying with oxygen content is suggested to be associated with excitation within the CuO chains in the preceding paper (Ye {ital et} {ital al}.).

• OSTI ID: 5689628
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 43:13; ISSN PRBMD; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ABSORPTION SPECTRA
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
FILMS
HIGH-TC SUPERCONDUCTORS
MATERIALS
OPTICAL PROPERTIES
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SEMICONDUCTOR MATERIALS
SPECTRA
SUPERCONDUCTORS
THIN FILMS
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES