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An equations-of-motion approach to quantum mechanics: application to a model phase transition

S. Y. Ho·G. Rosensteel·D. J. Rowe
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Abstract

We present a generalized equations-of-motion method that efficiently calculates energy spectra and matrix elements for algebraic models. The method is applied to a 5-dimensional quartic oscillator that exhibits a quantum phase transition between vibrational and rotational phases. For certain parameters, 10 by 10 matrices give better results than obtained by diagonalising 1000 by 1000 matrices.

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S. Y. Ho, G. Rosensteel, D. J. Rowe. 2006-11-07. An equations-of-motion approach to quantum mechanics: application to a model phase transition. https://doi.org/10.1103/physrevlett.98.080401

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