Universal Order Parameters and Quantum Phase Transitions: A Finite-Size Approach
Universal Order Parameters and Quantum Phase Transitions: A Finite-Size Approach
We propose a method to construct universal order parameters for quantum phase transitions in many-body lattice systems. The method exploits the H-orthogonality of a few near-degenerate lowest states of the Hamiltonian describing a given finite-size system, which makes it possible to perform finite-size scaling and take full advantage of currently …