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arXiv · 1511.07277

Atomic Quadrupole Moment Measurement Using Dynamic Decoupling

Ravid Shaniv·Nitzan Akerman·Roee Ozeri
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Abstract

We present a method that uses dynamic decoupling of a multi-level quantum probe to distinguish small frequency shifts that depend on $m^2_{j}$, where $m^2_{j}$ is the angular momentum of level $\left|j\right\rangle$ along the quantization axis, from large noisy shifts that are linear in $m_{j}$, such as those due to magnetic field noise. Using this method we measured the electric quadrupole moment of the $4D_{\frac{5}{2}}$ level in $^{88}Sr^{+}$ to be $2.973^{+0.026}_{-0.033}\, ea_{0}^{2}$. Our measurement improves the uncertainty of this value by an order of magnitude and thus helps mitigate an important systematic uncertainty in $^{88}Sr^{+}$ based optical atomic clocks and verifies complicated many-body quantum calculations.

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Ravid Shaniv, Nitzan Akerman, Roee Ozeri. 2015-11-23. Atomic Quadrupole Moment Measurement Using Dynamic Decoupling. https://doi.org/10.1103/physrevlett.116.140801

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