Probing Spin Correlations in a Bose-Einstein Condensate Near the Single-Atom Level
An Qu, Bertrand Evrard, Jean Dalibard, Fabrice Gerbier
Abstract
Using parametric conversion induced by a Shapiro-type resonance, we produce and characterize a two-mode squeezed vacuum state in a sodium spin 1 Bose-Einstein condensate. Spin-changing collisions generate correlated pairs of atoms in the m=±1 Zeeman states out of a condensate with initially all atoms in m=0. A novel fluorescence imaging technique with sensitivity ΔN∼1.6 atom enables us to demonstrate the role of quantum fluctuations in the initial dynamics and to characterize the full distribution of the final state. Assuming that all atoms share the same spatial wave function, we infer a squeezing parameter of 15.3 dB.
Topics & Concepts
PhysicsBose–Einstein condensateZeeman effectAtomic physicsSpin (aerodynamics)Atom (system on chip)Spin statesCondensed matter physicsQuantum mechanicsMagnetic fieldComputer scienceThermodynamicsEmbedded systemQuantum Information and CryptographyCold Atom Physics and Bose-Einstein CondensatesQuantum optics and atomic interactions