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arXiv · 0801.4796

Control of Four-Level Quantum Coherence via Discrete Spectral Shaping of an Optical Frequency Comb

Matthew C. Stowe·Avi Pe'er·Jun Ye
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Abstract

We present an experiment demonstrating high-resolution coherent control of a four-level atomic system in a closed (diamond) type configuration. A femtosecond frequency comb is used to establish phase coherence between a pair of two-photon transitions in cold Rb atoms. By controlling the spectral phase of the frequency comb we demonstrate the optical phase sensitive response of the diamond system. The high-resolution state selectivity of the comb is used to demonstrate the importance of the signs of dipole moment matrix elements in this type of closed-loop excitation. Finally, the pulse shape is optimized resulting in a 256% increase in the two-photon transition rate by forcing constructive interference between the mode pairs detuned from an intermediate resonance.

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Matthew C. Stowe, Avi Pe'er, Jun Ye. 2008-01-30. Control of Four-Level Quantum Coherence via Discrete Spectral Shaping of an Optical Frequency Comb. https://doi.org/10.1103/physrevlett.100.203001

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