Robust state preparation of a single trapped ion by adiabatic passage

Abstract

We report adiabatic passage experiments with a single trapped ion. By applying a frequency-chirped laser pulse with a Gaussian amplitude envelope, we reach a transfer efficiency of 0.99(1) on an optical transition from the electronic ground state S_1/2 to the metastable state D_5/2. This transfer method is shown to be insensitive to the accurate setting of laser parameters, and therefore is suitable as a robust tool for ion-based quantum computing.

Acknowledgments

We acknowledge support by the European Commission (QGates). ChW and ThH acknowledge financial support from Science Foundation Ireland under grant number 03/IN3/I397 and the Deutsche Forschungsgemeinschaft. TK acknowledges financial support by the FWF. FS-K acknowledges financial support by the Landesstiftung Baden-Württemberg.

Notes

†Due to the double-pass configuration, the modulation of laser frequency and phase is twice the applied rf-modulation. The gaussian chirped laser field waveform is revealed from the rf-waveform by the independently measured AOM transfer function.

‡Marconi Inc., Signal gen. 2019A.

§Brimrose Inc.,TEF-270-100.

Chiped laser pulses have been applied for cooling a sample of neutral Cs atoms trapped in the potentials formed by a Nd : YAG laser standing wave field. The chirp of the laser frequency allowed one in that application to overcome the inhomogeneous broadening of the red sideband transition frequency as a result of the slightly different trap frequencies of the Nd : YAG laser dipole potentials over the whole sample. This technique allowed one to prepare neutral atoms in the ground state of vibration, see 31.