"Photonic" cat states from strongly interacting matter waves

Abstract

We consider ultracold quantum gases of scalar bosons, residing in a coupling strength--density regime in which they constitute a twofold fragmented condensate trapped in a single well. It is shown that the corresponding quantum states are, in the appropriate Fock space basis, identical to the photon cat states familiar in quantum optics, which correspond to superpositions of coherent states of the light field with a phase difference of $\pi$. In marked distinction to photon cat states, the very existence of matter wave cat states however crucially depends on the many-body correlations of the constituent particles. We consequently establish that the quadratures of the effective "photons," expressing the highly nonclassical nature of the macroscopic matter wave superposition state, can be experimentally accessed by measuring the density-density correlations of the interacting quantum gas.

12 pages including the supplement, 1+3 figures; Schrödinger removed from the title at the request of PRL editors

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Cited by in corpus (23)

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• NOON state of Bose atoms in the double-well potential via an excited state quantum phase transition
• Variance of an anisotropic Bose-Einstein condensate
• Fragmentation and correlations in a rotating Bose-Einstein condensate undergoing breakup
• Attractive Bose-Einstein condensates in anharmonic traps: Accurate numerical treatment and the intriguing physics of the variance
• Photon pair condensation by engineered dissipation
• Protected cat states from kinetic driving of a boson gas
• Fast generation of Cat states in Kerr nonlinear resonators via optimal adiabatic control
• Stabilizing arrays of photonic cat states via spontaneous symmetry breaking
• Possibility to probe negative values of a Wigner function in scattering of a coherent superposition of electronic wave packets by atoms
• Progress towards quantum-enhanced interferometry with harmonically trapped quantum matter-wave bright solitons
• Macroscopic superpositions as quantum ground states
• Accelerated creation of NOON states with ultracold atoms via counterdiabatic driving
• Uncertainty product of an out-of-equilibrium Bose-Einstein condensate
• Unfolding multi-particle quantum correlations hidden in decoherence
• Fragmentation of identical and distinguishable bosons' pairs and natural geminals of a trapped bosonic mixture
• Multimode NOON-state generation with ultracold atoms via geodesic counterdiabatic driving
• Classical analogy of a cat state using vortex light
• A no-go result on observing quantum superpositions
• Tweezer interferometry with NOON states