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Structural and insulator-metal quantum phase transitions on a lattice

E. V. Tsiper·A. L. Efros
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Abstract

We consider 2D gas of spinless fermions with the Coulomb and the short range interactions on a square lattice at T=0. Using exact diagonalization technique we study finite clusters up to 16 particles at filling factors $ν=1/2$ and 1/6. By increasing the hopping amplitude we obtain the low-energy spectrum of the system in a wide range from the classical Wigner crystal to almost free gas of fermions. The most efforts are made to study the mechanism of the structural and insulator-metal transitions. We show that both transitions are determined by the energy band of the defect with the lowest energy in the Wigner crystal.

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E. V. Tsiper, A. L. Efros. 1997-08-20. Structural and insulator-metal quantum phase transitions on a lattice. https://doi.org/10.1103/physrevb.57.6949

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