Electronic Phase Transitions

Karl W. Böer

Ph. Brune, A. P. Kampf

Igor N. Karnaukhov, Ilya Eremin

We propose a strongly correlated (1+1)D electron model with particle–hole asymmetry which is exactly solvable by means of the nested Bethe ansatz. The particle–hole asymmetry in this many-body system causes a metal–insulator transition with a phase separation. Here, we give a detailed analysis of the zero-temperature phase diagram of the model and demonstrate how this unusual behavior of the metal–insulator transition with phase separation arises. In particular, we show that a homogeneous phase of itinerant electrons and a mixed phase of itinerant electrons and localized electron pairs (for which two different species reside in spatially separated regions) define the ground state of a fermion chain. We also find that the metal–insulator phase transition induces phase transition on the surface with simultaneous generation of the interphase boundary.

James G. Glimm, Arthur M. Jaffe

James G. Glimm, Arthur Jaffe

Abhijit C. Mehta, Cyrus J. Umrigar, Julia S. Meyer +1 more

We study the quantum phase transition of interacting electrons in quantum wires from a one-dimensional (1D) linear configuration to a quasi-1D zigzag arrangement using quantum Monte Carlo methods. As the density increases from its lowest values, first, the electrons form a linear Wigner crystal, then, the symmetry about the axis of the wire is broken as the electrons order in a quasi-1D zigzag phase, and, finally, the electrons form a disordered liquidlike phase. We show that the linear to zigzag phase transition is not destroyed by the strong quantum fluctuations present in narrow wires; it has characteristics which are qualitatively different from the classical transition.