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arXiv · 1707.02630

Auto-Balanced Ramsey Spectroscopy

Abstract

We devise a perturbation-immune version of Ramsey's method of separated oscillatory fields. Spectroscopy of an atomic clock transition without compromising the clock's accuracy is accomplished by actively balancing the spectroscopic responses from phase-congruent Ramsey probe cycles of unequal durations. Our simple and universal approach eliminates a wide variety of interrogation-induced line shifts often encountered in high precision spectroscopy, among them, in particular, light shifts, phase chirps, and transient Zeeman shifts. We experimentally demonstrate auto-balanced Ramsey spectroscopy on the light shift prone $^{171}$Yb$^{+}$ electric octupole optical clock transition and show that interrogation defects are not turned into clock errors. This opens up frequency accuracy perspectives below the $10^{-18}$ level for the Yb$^{+}$ system and for other types of optical clocks.

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Christian Sanner, Nils Huntemann, Richard Lange, Christian Tamm, Ekkehard Peik. 2017-07-09. Auto-Balanced Ramsey Spectroscopy. https://doi.org/10.1103/physrevlett.120.053602

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