Evolution of Magnetic and Superconducting Fluctuations with Doping of High- T c Superconductors
Abstract
Electronic Raman scattering from high- and low-energy excitations was studied as a function of temperature, extent of hole doping, and energy of the incident photons in Bi 2 Sr 2 CaCu 2 O 8±δ superconductors. For underdoped superconductors, short-range antiferromagnetic (AF) correlations were found to persist with hole doping, and doped single holes were found to be incoherent in the AF environment. Above the superconducting (SC) transition temperature T c , the system exhibited a sharp Raman resonance of B 1 g symmetry and energy of 75 millielectron-volts and a pseudogap for electron-hole excitations below 75 millielectron-volts, a manifestation of a partially coherent state forming from doped incoherent quasi particles. The occupancy of the coherent state increases with cooling until phase ordering at T c produces a global SC state.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 21, 1997
- Source ID
- 10.1126/science.278.5342.1427
Entities
People
- C. Kendziora
- G. Blumberg
- K. Kadowaki
- M. V. Klein
- Moonsoo Kang
Organizations
- United States Naval Research Laboratory
- University of Illinois Urbana–Champaign
- University of Tsukuba