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Dynamic Exponent of t-J and t-J-W Model

Hirokazu Tsunetsugu·Masatoshi Imada
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Abstract

Drude weight of optical conductivity is calculated at zero temperature by exact diagonalization for the two-dimensional t-J model with the two-particle term, $W$. For the ordinary t-J model with $W$=0, the scaling of the Drude weight $D \propto δ^2$ for small doping concentration $δ$ is obtained, which indicates anomalous dynamic exponent $z$=4 of the Mott transition. When $W$ is switched on, the dynamic exponent recovers its conventional value $z$=2. This corresponds to an incoherent-to-coherent transition associated with the switching of the two-particle transfer.

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Hirokazu Tsunetsugu, Masatoshi Imada. 1998-05-01. Dynamic Exponent of t-J and t-J-W Model. https://doi.org/10.1143/jpsj.67.1864

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