Squeezed states for Frenkel-like two-fermion composite bosons

Abstract

We investigate squeezed states of composite bosons (cobosons) formed by pairs of spin-$1/2$ fermions, with emphasis on Frenkel-like cobosons. While squeezing for standard bosonic modes is well established, its extension to cobosons requires accounting for Pauli blocking and the resulting non-canonical commutation algebra. Building on earlier constructions of coboson coherent states, we define squeezed cobosons as eigenstates of a Bogoliubov transformed coboson operator and derive explicit expressions for the associated quadrature variances. We show that the underlying fermionic structure leads to state-dependent modifications of the Heisenberg--Robertson uncertainty bound, which may fall below the canonical bosonic limit without implying any violation of uncertainty principles. Numerical results based on finite-dimensional matrix representations illustrate how these effects constrain the attainable squeezing. Our framework is relevant to composite boson systems such as tightly bound electron-hole pairs and provides a physically transparent setting to probe compositeness through observable quadrature fluctuations.

8 pages, 3 figures Small changes to the text and new references included

References in corpus (4)

• Spin squeezing in an ensemble of quadrupolar nuclei NMR system
• Microscopic derivation of Frenkel excitons in second quantization
• A fresh view on Frenkel excitons: Electron-hole pair exchange and many-body formalism
• Effect of Pauli blocking on coherent states of composite bosons