Measurement of Hyperfine Structure and the Zemach Radius in ^{6}Li^{+} Using Optical Ramsey Technique.

Area of Science:

• Atomic Physics
• Quantum Electrodynamics (QED)
• Nuclear Physics

Background:

• Accurate atomic spectroscopy is crucial for testing fundamental theories.
• Previous measurements of hyperfine splittings in Li+ had significant uncertainties.
• Discrepancies existed between experimental and theoretical values for nuclear properties.

Purpose of the Study:

• To achieve high-precision measurements of the 2^{3}S_{1}-2^{3}P_{J} transitions in ^{6}Li^{+} ions.
• To refine the hyperfine splittings of the 2^{3}S_{1} and 2^{3}P_{J} states.
• To determine an improved value for the Zemach radius of the ^{6}Li nucleus.

Main Methods:

• Utilized the optical Ramsey technique for high-precision spectroscopy.
• Measured hyperfine splittings of specific atomic states in ^{6}Li^{+} ions.
• Combined experimental data with quantum electrodynamic (QED) calculations.

Main Results:

• Achieved the most precise values for hyperfine splittings of the 2^{3}S_{1} and 2^{3}P_{J} states in ^{6}Li^{+}, with uncertainties as low as 10 kHz.
• Reduced experimental uncertainties by factors of 5 and 50 for the 2^{3}S_{1} and 2^{3}P_{J} states, respectively.
• Determined an improved Zemach radius of the ^{6}Li nucleus to be 2.44(2) fm, showing disagreement with simpler nuclear models.

Conclusions:

• The high-precision measurements validate advanced QED calculations.
• The determined Zemach radius challenges existing nuclear models, highlighting the need for more sophisticated nuclear physics input.
• Further investigation into nuclear structure is required for a definitive ^{6}Li Zemach radius.