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arXiv · 1208.0173

Unitary quantum phase operators for bosons and fermions: A model study on quantum phases of interacting particles in a symmetric double-well potential

Biswajit Das·Bitan Ghosal·Subhasish Dutta Gupta·Bimalendu Deb
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Abstract

We introduce unitary quantum phase operators for material particles. We carry out a model study on quantum phases of interacting bosons in a symmetric double-well potential in terms of unitary and commonly-used non-unitary phase operators and compare the results for different number of bosons. We find that the results for unitary quantum phase operators are significantly different from those for non-unitary ones especially in the case of low number of bosons. We introduce unitary operators corresponding to the quantum phase-difference between two single-particle states of fermions. As an application of fermionic phase operators, we study a simple model of a pair of interacting two-component fermions in a symmetric double-well potential. We also investigate quantum phase and number fluctuations to ascertain number-phase uncertainty in terms of unitary phase operators.

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Biswajit Das, Bitan Ghosal, Subhasish Dutta Gupta, Bimalendu Deb. 2013-01-13. Unitary quantum phase operators for bosons and fermions: A model study on quantum phases of interacting particles in a symmetric double-well potential. https://doi.org/10.1088/0953-4075%2F46%2F3%2F035501

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