Joffe-Pritchard traps

While the atomic trap based on the evanescent light wave uses a combination of laser field, static magnetic field and gravitational force the Joffe-Pritchard trap only... 

Fig. 9.24 (a) The two magnetic fields of a Joffe-Pritchard trap, (b) field lines of the total field... 

The phase transition to EEC manifests itself by the sudden increase of the atomic density (Fig. 9.32), which can be monitored by measuring the absorption of an expanded probe laser beam (Fig. 9.33). As example of EEC in a magnetic trap Eig. 9.34 shows the spatial confinement of the atomic cloud in a Z-shaped Joffe-Pritchard micro-trap (see Sect. 9.1.8b), where a homogeneous magnetic field in y-direction is superimposed to the field produced by the current through the wire. The volume of the atomic cloud is an ellipsoid with rotational symmetry around the z-axis. 

Ketterle W, Davis K B, Joffe M A, Martin A and Pritchard D 1993 High densities of cold atoms in a dark spontaneous-force optical trap Phys.Rev.Lett. 70 2253-6... 

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