STARK SHIFT OF A SINGLE BARIUM ION AND POTENTIAL APPLICATION TO ZERO-POINT CONFINEMENT IN A RT TRAP

Recently we have observed the Stark shift in an optical transition of a single trapped Ba+ ion. To enhance the shift in the 6S1/2-5D5/2 cloc k transition, the ion is displaced from the saddle point of the trappi ng potential. The Stark shift constants, sigma(s), for the three pairs of Zeeman components are found to be the following: 6.1(7), 7.5(8), a nd 11.7(12) mHz/(V/cm)2 for \M(S)\=1/2 to M(D)\=1/2, 3/2, and 5/2 tran sitions, respectively. A scheme is also proposed to use the Stark shif t to identify the zero-point confinement state of a single trapped Ba ion.