Atom confinement cooling

To achieve both laser cooling and entan ement, we need to provide a coupling between intonal and motional quantum states. This can be achieved with the application of inhomogeneous (classical) electromagnetic fields. For example, consider an atom confined in a 1-D harmonic potential. The atom s dipole moment is assumed to couple to an electric field (x,t) through the Hamiltonian... 

Therefore, tire dissipative force tenn cools tire collection of atoms as well as combining witli tire displacement tenn to confine tliem. The damping time constant z = is typically tens of microseconds. It is important to bear in... 

Single atomic ions confined in radio frequency traps and cooled by laser beams (Figure 7.4a) formed the basis for the first proposal of a CNOT quantum gate with an explicit physical system [14]. The first experimental realization of a CNOT quantum gate was in fact demonstrated on a system inspired by this scheme [37]. In this proposal, two internal electronic states of alkaline-earth or transition metal ions (e.g. Ba2+ or Yb3+) define the qubit basis. These states have excellent coherence properties, with T2 and T2 in the range of seconds [15]. Each qubit can be... 

Low-light fluorescence image of 1 million trapped rubidium atoms cooled to micro Kelvin temperatures. The gaseous atoms are confined at the intersection of three focused, off-resonant laser beams, and the image was taken by briefly illuminating the atoms with resonant laser light. (Andor Technology)... 

Atoms in an optical trap (Doppler cooling Wineland, et al., 1978 optical molasses Chu, et al., 1986 magneto-optic trap Steane and Foot, 1991 Helmerson, et al., 1992) are confined and cooled to translational temperatures on the order of << 1 mK. Ultracold collisions between such trapped atoms permit the recording of bound<—free spectra with resolution limited only by the translational temperature (1 mK, which corresponds to a frequency resolution of 7 x 10-4 cm-1) (Julienne and Mies, 1989 Lett, et al., 1995 Burnett, et al., 2002). This makes spectroscopically accessible the extremely long-range regions of potential energy curves (R >10A 5Re) and otherwise only indirectly observable weakly bound or repulsive electronic states. 

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