Recursively minimally-deformed oscillators

Abstract

A recursive deformation of the boson commutation relation is introduced. Each step consists of a minimal deformation of a commutator $[a,\ad]=f_k(\cdots;\no)$ into $[a,\ad]_{q_{k+1}}=f_k(\cdots;\no)$, where $\cdots$ stands for the set of deformation parameters that $f_k$ depends on, followed by a transformation into the commutator $[a,\ad]=f_{k+1}(\cdots,\, q_{k+1};\no)$ to which the deformed commutator is equivalent within the Fock space. Starting from the harmonic oscillator commutation relation $[a,\ad]=1$ we obtain the Arik-Coon and the Macfarlane-Biedenharn oscillators at the first and second steps, respectively, followed by a sequence of multiparameter generalizations. Several other types of deformed commutation relations related to the treatment of integrable models and to parastatistics are also obtained. The ``generic'' form consists of a linear combination of exponentials of the number operator, and the various recursive families can be classified according to the number of free linear parameters involved, that depends on the form of the initial commutator.