 NSFPAR ID:
 10431100
 Date Published:
 Journal Name:
 Nature
 Volume:
 610
 Issue:
 7932
 ISSN:
 00280836
 Page Range / eLocation ID:
 472 to 477
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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The creation and manipulation of quantum entanglement is central to improving precision measurements. A principal method of generating entanglement for use in atom interferometry is the process of spin squeezing whereupon the states become more sensitive to SU(2) rotations. One possibility to generate this entanglement is provided by oneaxis twisting (OAT), where a manyparticle entangled state of one degree of freedom is generated by a nonlinear Hamiltonian. We introduce a novel method which goes beyond OAT to create squeezing and entanglement across two distinct degrees of freedom. We present our work in the specific physical context of a system consisting of collective atomic energy levels and discrete collective momentum states, but also consider other possible realizations. Our system uses a nonlinear Hamiltonian to generate dynamics in SU(4), thereby creating the opportunity for dynamics not possible in typical SU(2) oneaxis twisting. This leads to three axes undergoing twisting due to the two degrees of freedom and their entanglement, with the resulting potential for a more rich context of quantum entanglement. The states prepared in this system are potentially more versatile for use in multiparameter or auxiliary measurement schemes than those prepared by standard spin squeezing.more » « less

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In a conventional atomic interferometer employing
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