P-21, Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Phys Rev Lett. 2013 Nov 15;111(20):205301. doi: 10.1103/PhysRevLett.111.205301. Epub 2013 Nov 11.
We report the creation of a pair of Josephson junctions on a toroidal dilute gas Bose-Einstein condensate (BEC), a configuration that is the cold atom analog of the well-known dc superconducting quantum interference device (SQUID). We observe Josephson effects, measure the critical current of the junctions, and find dynamic behavior that is in good agreement with the simple Josephson equations for a tunnel junction with the ideal sinusoidal current-phase relation expected for the parameters of the experiment. The junctions and toroidal trap are created with the painted potential, a time-averaged optical dipole potential technique which will allow scaling to more complex BEC circuit geometries than the single atom-SQUID case reported here. Since rotation plays the same role in the atom SQUID as magnetic field does in the dc SQUID magnetometer, the device has potential as a compact rotation sensor.
我们报告了在环形稀释玻色-爱因斯坦凝聚体（BEC）上创建一对约瑟夫森结，这种配置是众所周知的直流超导量子干涉装置（SQUID）的冷原子模拟。我们观察到约瑟夫森效应，测量了结的临界电流，并发现了与具有理想正弦电流-相位关系的隧道结的简单约瑟夫森方程非常吻合的动态行为，该关系是实验参数所预期的。结和环形陷阱是使用涂漆势创建的，这是一种时间平均的光学偶极力技术，它将允许扩展到比这里报道的单个原子-SQUID 情况更复杂的 BEC 电路几何形状。由于旋转在原子 SQUID 中起着与磁场在直流 SQUID 磁力计中相同的作用，因此该设备有可能成为一种紧凑的旋转传感器。
