Breaking the energy-symmetry blockade in magneto-optical rotation

Abstract

The magneto-optical polarization rotation effect has prolific applications in various research areas spanning the scientific spectrum including space and interstellar research, nano-technology and material science, biomedical imaging, and sub-atomic particle research. In nonlinear magneto-optical rotation (NMOR), the intensity of a linearly-polarized probe field affects the rotation of its own polarization plane while propagating in a magnetized medium. However, typical NMOR signals of conventional single-beam $\Lambda -$scheme atomic magnetometers are peculiarly small, requiring sophisticated magnetic shielding under complex operational conditions. Here, we show the presence of an energy-symmetry blockade that undermines the NMOR effect in conventional single-beam $\Lambda -$scheme atomic magnetometers. We further demonstrate, both experimentally and theoretically, an inelastic wave-mixing technique that breaks this NMOR blockade, resulting in more than five orders of magnitude ($>$300,000-fold) NMOR optical signal power spectral density enhancement never before seen with conventional single-beam $\Lambda -$scheme atomic magnetometers. This new technique, demonstrated with substantially reduced light intensities, may lead to many applications, especially in the field of bio-magnetism and high-resolution low-field magnetic imaging.

References in corpus (8)

• Optical Magnetometry
• Resonant nonlinear magneto-optical effects in atoms
• Polarized alkali vapor with minute-long transverse spin-relaxation time
• Enhancement of Magneto-Optic Effects via Large Atomic Coherence
• Suppression of Spin-Exchange Relaxation Using Pulsed Parametric Resonance
• Nonlinear Magneto-Optical Rotation of Elliptically Polarized Light
• Spin Relaxation Resonances Due to the Spin-Axis Interaction in Dense Rubidium and Cesium Vapor
• Optical control of Faraday rotation in hot Rb vapor