We theoretically investigate magneto-optical rotation (MOR) of a linearly polarized probe field in the four-level N-type cold atoms. By applying a static magnetic field and a weak coupling field, it is shown that the birefringence enhancement is induced in the system. Moreover, we show that the static magnetic field has a major role in switching the dichroism to enhanced birefringence in the system. We also obtain a large intensity for the output field with nearly perpendicular MOR angle by 88 degrees with subnatural width. It is demonstrated that Doppler broadening has a destructive effect on the MOR of the polarization direction of the probe field. The results of our study can be used for selecting narrow band of wavelengths and polarization converter for efficient switching of TM/TE polarization modes in optical communication, the depolarization backscattering lidar, polarization spectroscopy and precision measurements.We theoretically investigate magneto-optical rotation (MOR) of a linearly polarized probe field in the four-level N-type cold atoms. By applying a static magnetic field and a weak coupling field, it is shown that the birefringence enhancement is induced in the system. Moreover, we show that the static magnetic field has a major role in switching the dichroism to enhanced birefringence in the system. We also obtain a large intensity for the output field with nearly perpendicular MOR angle by 88 degrees with subnatural width. It is demonstrated that Doppler broadening has a destructive effect on the MOR of the polarization direction of the probe field. The results of our study can be used for selecting narrow band of wavelengths and polarization converter for efficient switching of TM/TE polarization modes in optical communication, the depolarization backscattering lidar, polarization spectroscopy and precision measurements.

Scientific ReportsApr 19, 201969 citations

Twists in nonlinear magneto-optic rotation with cold atoms

Paul D. Kunz, David H. Meyer, Fredrik K. Fatemi

We observe a narrow secondary dispersive feature nested within conventional nonlinear magneto-optical rotation (NMOR) signals obtained with a laser-cooled rubidium vapor. A similar feature has been previously named a "twist" by Budker et. al., in the context of warm vapor optical magnetometry [Phys. Rev. A. 81, 5788-5791 (1998)], and was ascribed to simultaneous optical pumping through multiple nearby hyperfine levels. In this work the twist is observed in a cold atom vapor, where the hyperfine levels are individually addressable, and thus is due to a different mechanism. We experimentally and numerically characterize this twist in terms of magnetic field strength, polarization, and optical intensity and find good agreement between our data and numerical models. We find that the twist width is proportional to the magnetic field in the transverse direction, and therefore two independent directions of the magnetic field can be measured simultaneously. This technique is useful as a simple and rapid in-situ method for nulling background magnetic fields.We observe a narrow secondary dispersive feature nested within conventional nonlinear magneto-optical rotation (NMOR) signals obtained with a laser-cooled rubidium vapor. A similar feature has been previously named a "twist" by Budker et. al., in the context of warm vapor optical magnetometry [Phys. Rev. A. 81, 5788-5791 (1998)], and was ascribed to simultaneous optical pumping through multiple nearby hyperfine levels. In this work the twist is observed in a cold atom vapor, where the hyperfine levels are individually addressable, and thus is due to a different mechanism. We experimentally and numerically characterize this twist in terms of magnetic field strength, polarization, and optical intensity and find good agreement between our data and numerical models. We find that the twist width is proportional to the magnetic field in the transverse direction, and therefore two independent directions of the magnetic field can be measured simultaneously. This technique is useful as a simple and rapid in-situ method for nulling background magnetic fields.

Optics ExpressJun 30, 20172 citations

Controlling Magneto-Optical Rotation via Atomic Coherences

Anil K. Patnaik, G. S. Agarwal

arXiv:quant-ph/9911034Springer eBooksJan 1, 20003 citations

Observation of magneto-optical rotation effects in cold $^{87}$ Rb atoms in an integrating sphereObservation of magneto-optical rotation effects in cold $^{87}$Rb atoms in an integrating sphere

Jinyin Wan, Yanling Meng, Ling Xiao +5 more

We present a modified scheme for detection of the magneto-optical rotation (MOR) effect, where a linearly polarized laser field is interacting with cold $^{87}$ Rb atoms in an integrating sphere. The rotation angle of the probe beam's polarization plane is detected in the experiment. The results indicate that the biased magnetic field, the probe light intensity and detuning, and the cold atoms' temperature are key parameters for the MOR effect. This scheme may improve the contrast of the rotation signal and provide an useful approach for high contrast cold atom clocks and magnetometers.We present a modified scheme for detection of the magneto-optical rotation (MOR) effect, where a linearly polarized laser field is interacting with cold $^{87}$Rb atoms in an integrating sphere. The rotation angle of the probe beam's polarization plane is detected in the experiment. The results indicate that the biased magnetic field, the probe light intensity and detuning, and the cold atoms' temperature are key parameters for the MOR effect. This scheme may improve the contrast of the rotation signal and provide an useful approach for high contrast cold atom clocks and magnetometers.

arXiv:1410.1990Oct 8, 20140 citations

Magneto-optical rotation in an atomic vapour

F. Schuller, M.J.D. Macpherson, Derek N. Stacey

Optics CommunicationsMay 1, 198929 citations

Observation of magneto-optical rotation effects in cold

^{87}

Rb atoms in an integrating sphere

We present a modified scheme for detection of the magneto-optical rotation (MOR) effect, where a linearly polarized laser field is interacting with cold

^{87}

Rb atoms in an integrating sphere. The rotation angle of the probe beam's polarization plane is detected in the experiment. The results indicate that the biased magnetic field, the probe light intensity and detuning, and the cold atoms' temperature are key parameters for the MOR effect. This scheme may improve the contrast of the rotation signal and provide an useful approach for high contrast cold atom clocks and magnetometers.