TY - JOUR
T1 - Self-heterodyne detection of the in situ phase of an atomic superconducting quantum interference device
AU - Mathew, R.
AU - Kumar, A.
AU - Eckel, S.
AU - Jendrzejewski, F.
AU - Campbell, G. K.
AU - Edwards, Mark
AU - Tiesinga, E.
N1 - Publisher Copyright:
© 2015 American Physical Society. ©2015 American Physical Society. us.
PY - 2015/9/3
Y1 - 2015/9/3
N2 - We present theoretical and experimental analysis of an interferometric measurement of the in situ phase drop across and current flow through a rotating barrier in a toroidal Bose-Einstein condensate (BEC). This experiment is the atomic analog of the rf-superconducting quantum interference device (SQUID). The phase drop is extracted from a spiral-shaped density profile created by the spatial interference of the expanding toroidal BEC and a reference BEC after release from all trapping potentials. We characterize the interferometer when it contains a single particle, which is initially in a coherent superposition of a torus and reference state, as well as when it contains a many-body state in the mean-field approximation. The single-particle picture is sufficient to explain the origin of the spirals, to relate the phase-drop across the barrier to the geometry of a spiral, and to bound the expansion times for which the in situ phase can be accurately determined. Mean-field estimates and numerical simulations show that the interatomic interactions shorten the expansion time scales compared to the single-particle case. Finally, we compare the mean-field simulations with our experimental data and confirm that the interferometer indeed accurately measures the in situ phase drop.
AB - We present theoretical and experimental analysis of an interferometric measurement of the in situ phase drop across and current flow through a rotating barrier in a toroidal Bose-Einstein condensate (BEC). This experiment is the atomic analog of the rf-superconducting quantum interference device (SQUID). The phase drop is extracted from a spiral-shaped density profile created by the spatial interference of the expanding toroidal BEC and a reference BEC after release from all trapping potentials. We characterize the interferometer when it contains a single particle, which is initially in a coherent superposition of a torus and reference state, as well as when it contains a many-body state in the mean-field approximation. The single-particle picture is sufficient to explain the origin of the spirals, to relate the phase-drop across the barrier to the geometry of a spiral, and to bound the expansion times for which the in situ phase can be accurately determined. Mean-field estimates and numerical simulations show that the interatomic interactions shorten the expansion time scales compared to the single-particle case. Finally, we compare the mean-field simulations with our experimental data and confirm that the interferometer indeed accurately measures the in situ phase drop.
UR - http://www.scopus.com/inward/record.url?scp=84941913381&partnerID=8YFLogxK
U2 - 10.1103/PhysRevA.92.033602
DO - 10.1103/PhysRevA.92.033602
M3 - Article
AN - SCOPUS:84941913381
SN - 1050-2947
VL - 92
JO - Physical Review A - Atomic, Molecular, and Optical Physics
JF - Physical Review A - Atomic, Molecular, and Optical Physics
IS - 3
M1 - 033602
ER -