Year: 2005
Type: article
Abstract: We calculate the Raman response contribution due to soft collective modes, finding a strong dependence on the photon polarizations and on the characteristic wave vectors of the modes. We compare our results with recent Raman spectroscopy experiments in underdoped cuprates, ${\mathrm{La}}_{2\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{CuO}}_{4}$ and $({\mathrm{Y}}_{1.97}{\mathrm{Ca}}_{0.3}){\mathrm{Ba}}_{2}{\mathrm{CuO}}_{6.05}$, where anomalous low-energy peaks are observed, which soften upon lowering the temperature. We show that the specific dependence on doping and on photon polarizations of these peaks can naturally arise from charge collective excitations at finite wavelength.
Source: Physical Review Letters
Authors: S. Caprara, C. Di Castro, M. Grilli, D. Suppa
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2037211891