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Transport Properties of Doped t-J Ladders

Hirokazu Tsunetsugu·Masatoshi Imada
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Abstract

Conductivity and Hall coefficient for various types of t-J ladders are calculated as a function of temperature and frequency by numerical diagonalization. A crossover from an incoherent to a coherent charge dynamics is found at a temperature T_{coh}. There exists another crossover at T_{PG} below which a pseudogap opens in the optical spectra, induced by the opening of a spin gap. In the absence of the spin gap, T_{coh} and the coherent weight are suppressed especially with increasing dimensionality. On the contrary, T_{coh} is strongly enhanced by the pseudogap formation below T_{PG}, where the coherent Drude weight decreases with increasing dimensionality. The Hall coefficient shows a strong crossover at T_{PG} below which it has large amplitude for small doping concentration.

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Hirokazu Tsunetsugu, Masatoshi Imada. 1997-05-27. Transport Properties of Doped t-J Ladders. https://doi.org/10.1143/jpsj.66.1876

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