Spin squeezing via quantum feedback
Abstract
We propose a quantum feedback scheme for producing deterministically reproducible spin squeezing. The results of a continuous nondemolition atom number measurement are fed back to control the quantum state of the sample. For large samples and strong cavity coupling, the squeezing parameter minimum scales inversely with atom number, approaching the Heisenberg limit. Furthermore, ceasing the measurement and feedback when this minimum has been reached will leave the sample in the maximally squeezed spin state.
- Publication:
-
Physical Review A
- Pub Date:
- June 2002
- DOI:
- 10.1103/PhysRevA.65.061801
- arXiv:
- arXiv:quant-ph/0202028
- Bibcode:
- 2002PhRvA..65f1801T
- Keywords:
-
- 42.50.Dv;
- 32.80.-t;
- 42.50.Lc;
- 42.50.Ct;
- Nonclassical states of the electromagnetic field including entangled photon states;
- quantum state engineering and measurements;
- Photon interactions with atoms;
- Quantum fluctuations quantum noise and quantum jumps;
- Quantum description of interaction of light and matter;
- related experiments;
- Quantum Physics;
- Condensed Matter
- E-Print:
- 4 pages, 3 figures, revtex4