Groß C. Spin Squeezing and Non-linear Atom Interferometry with Bose-Einstein Condensates

Springer, 2012. — 123 p. — (Springer Theses). — ISBN 978-3-642-25636-3.Interferometry, the most precise measurement technique known today, exploits the wave-like nature of the atoms or photons in the interferometer. As expected from the laws of quantum mechanics, the granular, particle-like features of the individually independent atoms or photons are responsible for the precision limit, the shot noise limit. However this “classical” bound is not fundamental and it is the aim of quantum metrology to overcome it by employing entanglement among the particles. This work reports on the realization of spin-squeezed states suitable for atom interferometry. Spin squeezing was generated on the basis of motional and spin degrees of freedom, whereby the latter allowed the implementation of a full interferometer with quantum-enhanced precision.Spin Squeezing, Entanglement and Quantum Metrology
Squeezing Two Mean Field Modes of a Bose–Einstein Condensate
Non-linear Interferometry Beyond the Standard Quantum Limit
Outlook
Appendix A. Precision Absorption Imaging of Ultracold Atoms
Appendix B. Particle Loss and Number Squeezing
Appendix C. Active Stabilization of Magnetic Fields Below the Milligauss Level