Josephson Junction Arrays with Bose-Einstein Condensates

We report on the direct observation of an oscillating atomic current in a one-dimensional array of Josephson junctions realized with an atomic Bose-Einstein condensate. The array is created by a laser standing wave, with the condensates trapped in the valleys of the periodic potential and weakly coupled by the interwell barriers. The coherence of multiple tunneling between adjacent wells is continuously probed by atomic interference. The square of the small-amplitude oscillation frequency is proportional to the microscopic tunneling rate of each condensate through the barriers and provides a direct measurement of the Josephson critical current as a function of the intermediate barrier heights. Our superfluid array may allow investigation of phenomena so far inaccessible to superconducting Josephson junctions and lays a bridge between the condensate dynamics and the physics of discrete nonlinear media.

[1]  M. Kasevich,et al.  Macroscopic quantum interference from atomic tunnel arrays , 1998, Science.

[2]  Wolfgang Ketterle,et al.  Bose–Einstein condensation of atomic gases , 2002, Nature.

[3]  Angel Sánchez,et al.  Collective Coordinates and Length-Scale Competition in Spatially Inhomogeneous Soliton-Bearing Equations , 1998, SIAM Rev..

[4]  A. Smerzi,et al.  Quantum Coherent Atomic Tunneling between Two Trapped Bose-Einstein Condensates , 1997, cond-mat/9706221.

[5]  R. Lutwak,et al.  Coherent Splitting of Bose-Einstein Condensed Atoms With Optically Induced Bragg Diffraction , 1999 .

[6]  J. W. Chamberlain Theory of planetary atmospheres , 1978 .

[7]  Alwyn C. Scott,et al.  Nonlinear Science: Emergence and Dynamics of Coherent Structures , 1999 .

[8]  J. G Doyle,et al.  The sun in time , 1993 .

[9]  Avenel,et al.  Josephson effect and quantum phase slippage in superfluids. , 1988, Physical review letters.

[10]  F Minardi,et al.  Superfluid and dissipative dynamics of a Bose-Einstein condensate in a periodic optical potential. , 2001, Physical review letters.

[11]  F. Dalfovo,et al.  Theory of Bose-Einstein condensation in trapped gases , 1998, cond-mat/9806038.

[12]  M. Kasevich,et al.  Squeezed States in a Bose-Einstein Condensate , 2001, Science.

[13]  W. Zurek The Environment, Decoherence and the Transition from Quantum to Classical , 1991 .

[14]  A. Leggett,et al.  Bose-Einstein condensation in the alkali gases: Some fundamental concepts , 2001 .

[15]  I. O. Kulik,et al.  Quantum mesoscopic phenomena and mesoscopic devices in microelectronics , 2000 .

[16]  M. I. Budyko,et al.  History of the Earth's atmosphere , 1987 .

[17]  Hans-Peter Schertl,et al.  Geochim. cosmochim. acta , 1989 .

[18]  H. Gove,et al.  NEUTRON THRESHOLD MEASUREMENTS USING THE CHALK RIVER TANDEM VAN DE GRAAFF ACCELERATOR , 1958 .

[19]  I. F. Quercia Physics and applications of the Josephson effect , 1984 .

[20]  S. Backhaus,et al.  Quantum oscillations between two weakly coupled reservoirs of superfluid 3He , 1997, Nature.

[21]  Y. Makhlin,et al.  Quantum-state engineering with Josephson-junction devices , 2000, cond-mat/0011269.

[22]  S. L. Barreto,et al.  Influence of dietary Vitamin E level on egg production of broiler breeders, and on the growth and immune response of progeny in comparison with the progeny from eggs injected with Vitamin E , 1998 .

[23]  A Smerzi,et al.  Discrete solitons and breathers with dilute Bose-Einstein condensates. , 2001, Physical review letters.