Quantum limited measurements of atomic scattering properties

Abstract

We propose a method to perform precision measurements of the interaction parameters in systems of N ultra-cold spin 1/2 atoms. The spectroscopy is realized by first creating a coherent spin superposition of the two relevant internal states of each atom and then letting the atoms evolve under a squeezing Hamiltonian. The non-linear nature of the Hamiltonian decreases the fundamental limit imposed by the Heisenberg uncertainty principle to N^(-2), a factor of N smaller than the fundamental limit achievable with non-interacting atoms. We study the effect of decoherence and show that even with decoherence, entangled states can outperform the signal to noise limit of non-entangled states. We present two possible experimental implementations of the method using Bose-Einstein spinor condensates and fermionic atoms loaded in optical lattices and discuss their advantages and disadvantages.

7 pages, 5 figures. References added

References in corpus (5)

• Generalized Limits for Single-Parameter Quantum Estimation
• Coherent collisional spin dynamics in optical lattices
• Enhancement of variation of fundamental constants in ultracold atom and molecule systems near Feshbach resonances
• Spontaneous dissociation of long-range Feshbach molecules
• Resonance reactions and enhancement of weak interactions in collisions of cold molecules

Cited by in corpus (10)

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• Spin squeezing in a generalized one-axis twisting model
• A nonlinear Ramsey interferometer operating beyond the Heisenberg limit
• Nonlinear quantum metrology using coupled nanomechanical resonators
• Spatially inhomogeneous phase evolution of a two-component Bose-Einstein condensate
• Parameter Estimation with Mixed-State Quantum Computation
• Magnetometry via a double-pass continuous quantum measurement of atomic spin
• Preparation of Decoherence Free Cluster States with Optical Superlattices
• Parameter Estimation, Model Reduction and Quantum Filtering
• Amplified Quantum Dynamics and Enhanced Parameter Sensitivity via Coherent Feedback in Collective Atomic Spin Systems