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arXiv · 2011.10145

Non-linear ladder operators and coherent states for the 2:1 oscillator

James Moran·Véronique Hussin·Ian Marquette
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Abstract

The 2:1 two-dimensional anisotropic quantum harmonic oscillator is considered and new sets of states are defined by means of normal-ordering non-linear operators through the use of non-commutative binomial theorems as well as solving recurrence relations. The states generated are good candidates for the natural generalisation of the $\mathfrak{su}(2)$ coherent states of the two-dimensional isotropic oscillator. The two-dimensional non-linear generalised ladder operators lead to several chains of states which are connected in a non trivial way. The uncertainty relations of the defining chain of states are calculated and it is found that they admit a resolution of the identity and the spatial distribution of the wavefunction produces Lissajous figures in correspondence with the classical 2:1 oscillator.

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James Moran, Véronique Hussin, Ian Marquette. 2021-06-22. Non-linear ladder operators and coherent states for the 2:1 oscillator. https://doi.org/10.1088/1751-8121%2Fac0200

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