Published July 1, 1991 | Version v1
Journal article

Anomalous shifts of oxygen-mode frequencies in La2-xSrxCuO4, YBa2Cu3O7-δ and Tl2Ba2Ca1-xGdxCu2O8

  • 1. J. Stefan Institute, Jamova 39, Ljubljana, (Yugoslavia)
  • 2. Institute for Polymers and Organic Solids, University of California, Santa Barbara, Santa Barbara, California 93106 (USA)
  • 3. E. I. Du Pont de Nemours, Central Research and Development, Experimental Station, P.O. Box 80328, Wilmington, Delaware 19880-0328 (USA)

Description

Comparison of photoinduced local modes (PILM's) of insulating YBa2Cu3O6.3 and Tl2Ba2Ca1-xGdxCu2O8 with Raman spectra of their metallic counterparts suggests that carrier injection anomalously increases the frequencies of phonons involving z-axis apex-oxygen motion in both the dilute (insulator) and concentrated (metallic) limit. In La2CuO4, we observe PILM's whose frequencies suggest a correspondence with the ''ghost modes'' observed in neutron scattering [Rietschel et al., Physica C 162--164, 1705 (1989)]. These data, together with Raman data on apex-oxygen anharmonicity, enable us to discuss the vibronic mode couplings involved in polaron formation in the three materials

Additional details

Publishing Information

Journal Title
Physical Review, B: Condensed Matter
Journal Volume
44
Journal Issue
1
Series
Phys. Rev., B: Condens. Matter.
Journal Page Range
237-241
ISSN
0163-1829
CODEN
PRBMD