Optical properties of severely overdoped La<sub>1.75</sub>Sr<sub>0.25</sub>CuO<sub>4</sub>
ORAL
Abstract
The temperature dependence of the optical properties of the severely overdoped cuprate La1.75Sr0.25CuO4 have been determined above and below the critical temperature Tc ~16 K over a wide frequency range for light polarized in the a-b plane. The real part of the optical conductivity can be reproduced reasonably well at low frequency using a simple Drude model, yielding an estimate for the plasma frequency wpD ~ 9300 cm-1. Below Tc the superconducting plasma frequency wps ~ 2700 cm-1 is determined from the Ferrell-Glover-Tinkham sum rule, indicating that less than 8% of the free carriers collapse into the superconducting condensate, in agreement with a recent study [1]. However, there is unusual structure below ~0.1 eV that suggests that the free-carrier scattering rate is strongly renormalized with frequency. In addition, the nature of the magnetic susceptibility through the superconducting transition suggests that this compound may not be homogeneous.
[1] I. Bozovic et al., Nature 536, 309 (2016).
[1] I. Bozovic et al., Nature 536, 309 (2016).
*Supported by DOE-BES under DE-SC0012704.
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Presenters
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Christopher Homes
- Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory