Two-magnon Raman scattering in cuprate superconductors: Evolution of magnetic fluctuations with doping
G. Blumberg, R. Liu, M. V. Klein, W. C. Lee, D. M. Ginsberg, C. Gu, B. W. Veal, B. Dabrowski
DOI 10.1103/PhysRevB.49.13295 · Physical Review B
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Abstract
We report observation and resonance Raman studies of spin-pair excitations in YBa2Cu3O6+x (0.37<x<0.7) and YBa2Cu4O8 superconductors. These excitations at energy ∼3J (2700±150 cm−1), similar to two-magnon excitations in insulators, are evidence that antiferromagnetic fluctuations with spatial extent of at least three lattice constants are not overdamped in the underdoped superconductors. With optimal hole dopings, where Tc>80 K, the two-magnon peak can no longer be seen above the flat Raman continuum. Photoluminescence and the origin of the broad-spectrum Raman continuum are also discussed.
Source-reported materials — not catalogue approval
| Formula | Reported Tc (K) | Pressure (GPa) | Type |
|---|---|---|---|
| YBa2Cu3O6+x Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 13 | Pressure not reported | unknown |
| YBa2Cu3O6+x Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 70 | Pressure not reported | unknown |
| YBa2Cu3O6+x Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 92 | Pressure not reported | unknown |
| YBa2Cu3O6+x Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 60 | Pressure not reported | unknown |
| YBa2Cu3O6+x Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 90 | Pressure not reported | unknown |
| YBa2Cu4O8 Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula. | 80 | Pressure not reported | unknown |