Rydberg electromagnetically induced transparency based laser lock to Zeeman sublevels with 0.6 GHz scanning range.

Area of Science:

• Atomic, Molecular, and Optical Physics
• Quantum Optics
• Laser Spectroscopy

Background:

• Rydberg atoms are highly sensitive to external fields, making precise laser control crucial.
• Electromagnetically induced transparency (EIT) provides a narrow spectral feature for laser locking.
• Zeeman effects split atomic energy levels in response to magnetic fields, influencing spectral features.

Purpose of the Study:

• To present a novel technique for frequency locking a laser to specific transitions in 87Rubidium.
• To achieve continuous laser frequency tuning over a 0.6 GHz range using an applied magnetic field.
• To improve laser frequency stability and reduce polarization-dependent shifts for applications in Rydberg atom research.

Main Methods:

• Utilizing the 5P3/2 intermediate and 32D5/2 Rydberg states in 87Rb.
• Employing electromagnetically induced transparency (EIT) with a 480 nm pump laser.
• Locking the laser frequency to Zeeman-split EIT peaks in the presence of an external magnetic field.

Main Results:

• Achieved continuous frequency tuning of 0.6 GHz by varying the magnetic field.
• Demonstrated short-term frequency stability of 0.15 MHz and long-term stability within 0.5 MHz.
• Reduced polarization-dependent frequency shift variation from 1.6 MHz to 0.6 MHz by locking to Zeeman sublevels.

Conclusions:

• The proposed laser frequency locking technique offers stable and tunable operation for Rydberg atom experiments.
• This method significantly reduces unwanted frequency shifts caused by laser polarization variations.
• The technique is valuable for research requiring precise and continuously tunable laser sources interacting with Rydberg states.