Holger MuellerUC Berkeley In quantum metrology and quantum information processing, a nonclassical state must undergo a quantum process before unwanted interactions with the environment lead to decoherence. In atom interferometry, the nonclassical state is a coherent spatial superposition of partial wave packets and the process might be, e.g., accumulation of sufficient phase shift to allow detection of extremely weak interactions, such as the gravitational field of a small proof mass. The coherence in atomic fountains is limited by the available free-fall time in Earth’s gravitational field. This can be overcome by suspending the wave packets in an optical lattice, which has so far reached up to 20 s of coherence,…
Holger Mueller has been advancing the physics of matter waves to probe nature at the utmost sensitivity. Examples are atom interferometry to measure gravity and the fine structure constant, phase-contrast electron microscopy, and optical recording of biological signals. He is a member of the Berkeley Physics Department, of Berkeley’s quantitative biology center QB3 as well as a faculty scientist at Lawrence Berkeley National Laboratory LBNL.