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Ground-state phase diagram of the one-dimensional dimerized t-J model at quarter filling

S. Nishimoto·Y. Ohta
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Abstract

The ground state of the one-dimensional dimerized $t$$-$$J$ model at quarter filling is studied by a Lanczos exact-diagonalization technique on small clusters. We calculate the charge gap, spin gap, binding energy, Tomonaga-Luttinger-liquid parameter, Drude weight, anomalous flux quantization, etc. We thereby show that the two types of dimerization, i.e., a dimerization of hopping integral and a dimerization of exchange interaction play a mutually competing role in controlling the ground state of the system and this leads to the emergence of various phases including the Mott insulating, Tomonaga-Luttinger-liquid, and Luther-Emery-liquid phases. The ground-state phase diagram of the model is given on the parameter space of the dimerizations.

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S. Nishimoto, Y. Ohta. 1998-05-22. Ground-state phase diagram of the one-dimensional dimerized t-J model at quarter filling. https://doi.org/10.1103/physrevb.59.4738

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