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 clock transition, the ion is displaced from the saddle point of the trapping 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), and 11.7(12) mHz/(V/cm)2 for \M(S)\=1/2 to M(D)\=1/2, 3/2, and 5/2 transitions, respectively. A scheme is also proposed to use the Stark shift to identify the zero-point confinement state of a single trapped Ba+ ion.