Observation of rubidium two photon excitation spectra in magnetic field

We precisely investigate the Zeeman and Paschen-Back effects of the hyperfine structure during the rubidium $5{\phantom{\rule{0.16em}{0ex}}}^{2}{S}_{1/2}\ensuremath{\rightarrow}5{\phantom{\rule{0.16em}{0ex}}}^{2}{D}_{5/2}$ two-photon transition. Owing to the high sensitivity of the $D$ state of atoms to a magnetic field, the splittings of the spectra of the $D$ state are sufficiently large in a weak magnetic field of $<10$ G. We experimentally observe how in the hyperfine coupling in the $5{\phantom{\rule{0.16em}{0ex}}}^{2}{D}_{5/2}$ state is disrupted even in weak magnetic fields around 10 G and the energy levels are arranged according to their total angular momentum $J$ and nuclear spin $I$ . The transient of the spectra known as the Paschen-Back effect is observed even in a weak magnetic field with an order of magnitude of several tens of gauss. The results of theoretical calculations for energy shifts and transition intensities under a magnetic field are in quantitative agreement with the experimental results.We precisely investigate the Zeeman and Paschen-Back effects of the hyperfine structure during the rubidium $5{\phantom{\rule{0.16em}{0ex}}}^{2}{S}_{1/2}\ensuremath{\rightarrow}5{\phantom{\rule{0.16em}{0ex}}}^{2}{D}_{5/2}$ two-photon transition. Owing to the high sensitivity of the $D$ state of atoms to a magnetic field, the splittings of the spectra of the $D$ state are sufficiently large in a weak magnetic field of $<10$ G. We experimentally observe how in the hyperfine coupling in the $5{\phantom{\rule{0.16em}{0ex}}}^{2}{D}_{5/2}$ state is disrupted even in weak magnetic fields around 10 G and the energy levels are arranged according to their total angular momentum $J$ and nuclear spin $I$. The transient of the spectra known as the Paschen-Back effect is observed even in a weak magnetic field with an order of magnitude of several tens of gauss. The results of theoretical calculations for energy shifts and transition intensities under a magnetic field are in quantitative agreement with the experimental results.

Physical Review AMay 28, 20194 citations

Synchronous coherent population trapping and its magnetic spectral response in rubidium vapor

G. S. Pati, Renu Tripathi, Raghwinder Singh Grewal +2 more

This paper reports experimental investigations of the spectral response of synchronous coherent population trapping (CPT) for magnetometry applications. Synchronous CPT is demonstrated using resonant two-photon excitation with a modulated bichromatic laser field in the $^{87}\mathrm{Rb} {D}_{1}$ manifold. Spectra containing multiple magnetic resonances are produced due to two-photon excitations created by various frequency components of the modulated beam. Theoretical modeling based on the atomic density-matrix equations is used to simulate the spectral response of synchronous CPT. Our results show potential advantages of synchronous CPT over synchronous optical pumping for magnetic field measurement. Magnetic resonance signals produced by synchronous CPT can be used in eliminating the dead-zone problem and also in determining the magnetic field direction.This paper reports experimental investigations of the spectral response of synchronous coherent population trapping (CPT) for magnetometry applications. Synchronous CPT is demonstrated using resonant two-photon excitation with a modulated bichromatic laser field in the $^{87}\mathrm{Rb} {D}_{1}$ manifold. Spectra containing multiple magnetic resonances are produced due to two-photon excitations created by various frequency components of the modulated beam. Theoretical modeling based on the atomic density-matrix equations is used to simulate the spectral response of synchronous CPT. Our results show potential advantages of synchronous CPT over synchronous optical pumping for magnetic field measurement. Magnetic resonance signals produced by synchronous CPT can be used in eliminating the dead-zone problem and also in determining the magnetic field direction.

Physical Review ASep 24, 202113 citations

Anomalous two-photon spectral features in warm rubidium vapor

Christopher Perrella, P. S. Light, Thomas J. Milburn +3 more

We report observation of anomalous fluorescence spectral features in the environs of a two-photon transition in a rubidium vapor when excited with two different wavelength lasers that are both counterpropagating through the vapor. These features are characterized by an unusual trade-off between the detunings of the driving fields. Three different hypothetical processes are presented to explain the observed spectra: a simultaneous three-atom and four-photon collision, a four-photon excitation involving a light field produced via amplified spontaneous emission, and population pumping perturbing the expected steady-state spectra. Numerical modeling of each hypothetical process is presented, supporting the population pumping process as the most plausible mechanism.We report observation of anomalous fluorescence spectral features in the environs of a two-photon transition in a rubidium vapor when excited with two different wavelength lasers that are both counterpropagating through the vapor. These features are characterized by an unusual trade-off between the detunings of the driving fields. Three different hypothetical processes are presented to explain the observed spectra: a simultaneous three-atom and four-photon collision, a four-photon excitation involving a light field produced via amplified spontaneous emission, and population pumping perturbing the expected steady-state spectra. Numerical modeling of each hypothetical process is presented, supporting the population pumping process as the most plausible mechanism.

Physical Review ASep 1, 20160 citations

D

state of atoms to a magnetic field, the splittings of the spectra of the

D

state are sufficiently large in a weak magnetic field of

<10

G. We experimentally observe how in the hyperfine coupling in the

5{\phantom{\rule{0.16em}{0ex}}}^{2}{D}_{5/2}

state is disrupted even in weak magnetic fields around 10 G and the energy levels are arranged according to their total angular momentum

J

and nuclear spin

I

. The transient of the spectra known as the Paschen-Back effect is observed even in a weak magnetic field with an order of magnitude of several tens of gauss. The results of theoretical calculations for energy shifts and transition intensities under a magnetic field are in quantitative agreement with the experimental results.

^{87}\mathrm{Rb} {D}_{1}

manifold. Spectra containing multiple magnetic resonances are produced due to two-photon excitations created by various frequency components of the modulated beam. Theoretical modeling based on the atomic density-matrix equations is used to simulate the spectral response of synchronous CPT. Our results show potential advantages of synchronous CPT over synchronous optical pumping for magnetic field measurement. Magnetic resonance signals produced by synchronous CPT can be used in eliminating the dead-zone problem and also in determining the magnetic field direction.