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arXiv · 0901.0689

Spin Dynamics in Cuprates: Optical Conductivity of HgBa2CuO4

J. Yang·J. Hwang·E. Schachinger·J. P. Carbotte·R. P. S. M. Lobo·D. Colson·A. Forget·T. Timusk
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Abstract

The electron-boson spectral density function I^2ChiOmega responsible for carrier scattering of the high temperature superconductor HgBa2CuO4 (Tc = 90 K) is calculated from new data on the optical scattering rate. A maximum entropy technique is used. Published data on HgBa2Ca2Cu3O8 (Tc = 130 K) are also inverted and these new results are put in the context of other known cases. All spectra (with two notable exceptions) show a peak at an energy (Omega_r) proportional to the superconducting transition temperature Omega_r ~= 6.3 kB.Tc. This charge channel relationship follows closely the magnetic resonance seen by polarized neutron scattering, Omega_r^{neutron} ~= 5.4 kB.Tc. The amplitudes of both peaks decrease strongly with increasing temperature. In some cases, the peak at Omega_r is weak and the spectrum can have additional maxima and a background extending up to several hundred meV.

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J. Yang, J. Hwang, E. Schachinger, J. P. Carbotte, R. P. S. M. Lobo, D. Colson, A. Forget, T. Timusk. 2009-01-06. Spin Dynamics in Cuprates: Optical Conductivity of HgBa2CuO4. https://doi.org/10.1103/physrevlett.102.027003

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