Measurement of a weak transition moment using two-pathway coherent control

We present a technique based upon two-pathway coherent control for the measurement of a weak transition moment. In our approach, we use two coherent optical beams, one the second harmonic of the other, to drive a transition by means of three distinct optical interactions. The interference between these interactions allows a determination of one moment relative to another. In this work, we demonstrate the approach by applying it to an experimental determination of the magnetic dipole moment for the 6s0.222222em0ex²S1/2→7s0.222222em0ex²S1/2 transition in atomic cesium. Our results are in excellent agreement with previous single-beam measurements. We also discuss prospects for extending this measurement technique to a new determination of the weak-force induced parity-nonconserving moment on this same transition.