Bose-Einstein Condensate Comagnetometer

Area of Science:

• Atomic physics
• Quantum optics
• Condensed matter physics

Background:

• Comagnetometers are crucial for precision measurements.
• Spinor Bose-Einstein condensates (BECs) offer unique quantum properties for sensing.
• Previous methods faced limitations in sensitivity and coherence time.

Purpose of the Study:

• To develop a high-sensitivity comagnetometer using a rubidium-87 BEC.
• To leverage the opposing gyromagnetic ratios of hyperfine states for enhanced common-mode rejection.
• To extend the coherence time of the magnetometer for longer measurement durations.

Main Methods:

• Utilizing the f=1 and f=2 ground state hyperfine manifolds of a ^{87}Rb spinor BEC as colocated magnetometers.
• Employing nondestructive Faraday rotation probing to independently measure transverse magnetizations and azimuth angles.
• Implementing spin-dependent interactions to suppress hyperfine-relaxing collisions in the f=2 manifold.

Main Results:

• Demonstrated a common-mode rejection of 44.0(8) dB, consistent with theoretical predictions.
• Extended the magnetometer coherence time to approximately 1 second.
• Successfully utilized spin-dependent interactions to inhibit hyperfine-relaxing collisions.

Conclusions:

• The developed ^{87}Rb BEC comagnetometer offers a promising platform for high-sensitivity measurements.
• The technique shows potential for searches for new physics, precision collision studies, and quantum spin dynamics.
• Extended coherence times significantly enhance the capabilities for precision measurements.