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Momentum dependent relaxation rate and pseudogap in doped magnetic insulators

M. M. Zemljic·P. Prelovsek
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Abstract

The spectral functions and corresponding self energies are calculated within the planar t-t'-J model as relevant to hole-doped cuprates using the exact diagonalization method at finite temperatures, combined with the averaging over twisted boundary conditions. Results show truncated Fermi surface at low doping and t'<0 in the antinodal region while the self energy reveals weakly k- and doping dependent anomalous relaxation rate |Σ''(k,ω)|~ a+b|ω| for ω<0, consistent with recent ARPES results, and a pseudogap-generating component of Lorentzian form. The latter is well pronounced at low doping and strongly depends on k and t'.

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M. M. Zemljic, P. Prelovsek. 2006-08-14. Momentum dependent relaxation rate and pseudogap in doped magnetic insulators. https://doi.org/10.1103/physrevb.75.104514

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