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On the metal-insulator transition in the two-chain model of correlated fermions

H. J. Schulz
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Abstract

The doping-induced metal-insulator transition in two-chain systems of correlated fermions is studied using a solvable limit of the t-J model and the fact that various strong- and weak-coupling limits of the two-chain model are in the same phase, i.e. have the same low-energy properties. It is shown that the Luttinger-liquid parameter K_ρtakes the universal value unity as the insulating state (half-filling) is approached, implying dominant d-type superconducting fluctuations, independently of the interaction strength. The crossover to insulating behavior of correlations as the transition is approached is discussed.

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H. J. Schulz. 1998-07-24. On the metal-insulator transition in the two-chain model of correlated fermions. https://doi.org/10.1103/physrevb.59.r2471

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