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تسجيل مستخدم جديدInfrared signatures of charge stripes in La(2-x)Sr(x)CuO(4)
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The in-plane optical conductivity of seven La(2-x)Sr(x)CuO(4) single crystals with x between 0 and 0.15 has been studied from 30 to 295 K. All doped samples exhibit strong peaks in the far-infrared, which closely resemble those observed in Cu-O ladders with one-dimensional charge-ordering. The behavior with doping and temperature of the peak energy, width, and intensity allows us to conclude that we are observing charge stripes dynamics in La(2-x)Sr(x)CuO(4) on the fast time scale of infrared spectroscopy.
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We investigate the hole and lattice dynamics in a prototypical high temperature superconducting system La{2-x}Sr{x}CuO{4} using infrared spectroscopy. By exploring the anisotropy in the electronic response of CuO2 planes we show that our results supp
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rillouin zone demonstrates that the magnetic scattering at intermediate energies, $20 lesssim omega lesssim 100$ meV, progressively decreases with over-doping. This strongly suggests that the magnetism is not related to Fermi surface nesting, but rather is associated with a decreasing volume fraction of (probably fluctuating) antiferromagnetic bubbles.
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{rm c}$ from 38K at ambient pressure to 51.6K at 8GPa. We find that the variation of $T_{rm c}$ scales as a function of $rho_c$, and that the c-axis pressure coefficient is much stronger than the ab-axis one. These imply that $T_{rm c}$ depends primarily on the interlayer, rather than the in-plane, lattice parameter.
By using new and previous measurements of the $ab$-plane conductivity $sigma_1^{ab} (omega,T)$ of La$_{2-x}$Sr$_x$CuO$_{4}$ (LSCO) it is shown that the spectral weight $W = int_0^Omega {sigma_1^{ab} (omega,T) domega}$ obeys the same law $W = W_0 - B(
Omega) T^2$ which holds for a conventional metal like gold, for $Omega$s below the plasma frequency. However $B(Omega)$, which measures the thermal response of the charge system, in LSCO exhibits a peculiar behavior which points towards correlation effects. In terms of hopping models, $B(Omega)$ is directly related to an energy scale $t_T$, smaller by one order of magnitude than the full bandwidth $t_0 sim W_0$.
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