Atomic Quadrupole Moment Measurement Using Dynamic Decoupling.

Area of Science:

• Quantum physics
• Atomic spectroscopy
• Quantum metrology

Background:

• Distinguishing small frequency shifts from large noisy shifts is crucial for precise measurements.
• Magnetic field noise and angular momentum-dependent shifts complicate quantum measurements.
• Accurate measurements of atomic properties are vital for advancing atomic clocks.

Purpose of the Study:

• To develop a method for distinguishing frequency shifts dependent on m_j^2 from linear m_j shifts.
• To measure the electric-quadrupole moment of the 4D_{5/2} level in ^{88}Sr^{+} with improved uncertainty.
• To mitigate systematic uncertainties in ^{88}Sr^{+} optical atomic clocks.

Main Methods:

• Utilizing dynamic decoupling of a multilevel quantum probe.
• Applying the technique to resolve frequency shifts related to m_j^2 and m_j.
• Measuring the electric-quadrupole moment of the 4D_{5/2} level in ^{88}Sr^{+}.

Main Results:

• Successfully distinguished small m_j^2-dependent frequency shifts from large m_j-dependent noisy shifts.
• Measured the electric-quadrupole moment of the 4D_{5/2} level in ^{88}Sr^{+} to be 2.973_{-0.033}^{+0.026}ea_{0}^{2}.
• Improved the uncertainty of this measurement by an order of magnitude.

Conclusions:

• The developed method effectively mitigates systematic uncertainties in ^{88}Sr^{+} optical atomic clocks.
• The precise measurement verifies complex many-body quantum calculations.
• This advancement contributes to the development of more accurate atomic clock technologies.