Quantum-limited velocity readout and quantum feedback cooling of a trapped ion via electromagnetically induced transparency

Journal Article · Sat Oct 15 04:00:00 EDT 2005 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.72.043823· OSTI ID:20718815

Rabl, P; Steixner, V; Zoller, P ^[1]

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1. Institute for Theoretical Physics, University of Innsbruck, and Institute for Quantum Optics and Quantum Information of the Austrian Academy of Science, 6020 Innsbruck (Austria)

We discuss continuous observation of the momentum of a single atom by employing the high velocity sensitivity of the index of refraction in a driven {lambda}-system based on electromagnetically induced transparency. In the ideal limit of unit collection efficiency this provides a quantum-limited measurement with minimal backaction on the atomic motion. A feedback loop, which drives the atom with a force proportional to measured signal, provides a cooling mechanism for the atomic motion. We derive the master equation which describes the feedback cooling and show that in the Lamb-Dicke limit the steady state energies are close to the ground state, limited only by the photon collection efficiency. Outside of the Lamb-Dicke regime the predicted temperatures are well below the Doppler limit.

• OSTI ID: 20718815
• Journal Information: Physical Review. A, Journal Name: Physical Review. A Journal Issue: 4 Vol. 72; ISSN 1050-2947; ISSN PLRAAN
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ATOMS
COOLING
FEEDBACK
GROUND STATES
IONS
OPACITY
PHOTONS
QUANTUM MECHANICS
RADIATION PRESSURE
REFRACTIVE INDEX
SENSITIVITY
TRAPPING
VELOCITY