There has been much interest in the influence of the laser noise on the atomic system. So far theoretical works have been performed on calculation of the mean values and the variance of the fluctuated atomic populations, and verified through observation of the fluctuating resonance fluorescence from the atomic vapors. Yabuzaki et al. have observed the excess intensity noise of the resonant light from a diode laser propagated through alkali atomic vapor. They have measured the intensity power spectrum of the light when the laser was tuned near the D2 line of Cs and observed all corresponding hyperfine-splitting resonances in the excited state and Zeeman splitting resonances within a hyperfine level of the ground state. Walser et al. have theoretically studied the intensity fluctuation of laser light propagated through a weakly absorbing medium. The calculated power spectrum of a phase-diffusing field has been found qualitative agreement with the experimental results by Yabuzaki et al. on hyperfine-splitting resonances. Recently, Mitsui has reported a new type of noise spectroscopy with a highly stabilized diode laser. He has investigated the spontaneous noise appeared in optical detection of magnetic resonance of Rb atoms. In this note we report the first observation of hyperfine spectra in the ground state of K and K appearing as the intensity fluctuation at hyperfine splittings of 462MHz and 254MHz of circularly polarized light from a diode laser transmitted through a sample cell. We have also observed the Zeeman hyperfine spectra of K in a static magnetic field. We show that the spectra are strongly dependent of the direction of the static magnetic field. Their splittings as functions of the strength of static magnetic field are compared with the Breit–Rabi formula. The experimental apparatus is quite simple as shown in Fig. 1. The diode laser used was an ordinary Fabry–Perot type with output power of 5mW, operating near the D1 line (769.9 nm) of K atoms. The output of the laser was circularly polarized and applied to a cell containing K vapor at a temperature 90 C, corresponding atomic density to be about 1:15 10 cm 3. The transmitted light was detected by an avalanche photo-diode having frequency response up to 1GHz. The output of the photo-diode was applied to a rf frequency analyzer to obtain the power spectrum of the fluctuation of the transmitted light intensity. A static magnetic field is provided by two pairs of Helmholtz coils mutually perpendicular and about 90 cm in diameter. The strength of the magnetic field is calibrated by using magnetic resonance signals of optically pumped Rb atoms. Figure 2 shows the frequency spectrum of the intensity fluctuation of transmitted light observed when the laser was tuned to the transition from the state F 1⁄4 1 in the ground state to the state F0 1⁄4 1 in the excited state by adjusting the driving current of the laser diode. Sharp resonance signals can be seen at the hyperfine splittings of K and K, 462 and 254MHz, respectively, on the background of broad noise spectrum. When a weak static magnetic field H0 is applied to the K vapor, the hyperfine spectra of K splits into several lines (the effective gyro-magnetic ratio of K is known to be 1⁄4 2 700 kHz/G). Figures 3(a) and 3(b) show the observed Zeeman hyperfine spectra of K forThere has been much interest in the influence of the laser noise on the atomic system. So far theoretical works have been performed on calculation of the mean values and the variance of the fluctuated atomic populations, and verified through observation of the fluctuating resonance fluorescence from the atomic vapors. Yabuzaki et al. have observed the excess intensity noise of the resonant light from a diode laser propagated through alkali atomic vapor. They have measured the intensity power spectrum of the light when the laser was tuned near the D2 line of Cs and observed all corresponding hyperfine-splitting resonances in the excited state and Zeeman splitting resonances within a hyperfine level of the ground state. Walser et al. have theoretically studied the intensity fluctuation of laser light propagated through a weakly absorbing medium. The calculated power spectrum of a phase-diffusing field has been found qualitative agreement with the experimental results by Yabuzaki et al. on hyperfine-splitting resonances. Recently, Mitsui has reported a new type of noise spectroscopy with a highly stabilized diode laser. He has investigated the spontaneous noise appeared in optical detection of magnetic resonance of Rb atoms. In this note we report the first observation of hyperfine spectra in the ground state of K and K appearing as the intensity fluctuation at hyperfine splittings of 462MHz and 254MHz of circularly polarized light from a diode laser transmitted through a sample cell. We have also observed the Zeeman hyperfine spectra of K in a static magnetic field. We show that the spectra are strongly dependent of the direction of the static magnetic field. Their splittings as functions of the strength of static magnetic field are compared with the Breit–Rabi formula. The experimental apparatus is quite simple as shown in Fig. 1. The diode laser used was an ordinary Fabry–Perot type with output power of 5mW, operating near the D1 line (769.9 nm) of K atoms. The output of the laser was circularly polarized and applied to a cell containing K vapor at a temperature 90 C, corresponding atomic density to be about 1:15 10 cm 3. The transmitted light was detected by an avalanche photo-diode having frequency response up to 1GHz. The output of the photo-diode was applied to a rf frequency analyzer to obtain the power spectrum of the fluctuation of the transmitted light intensity. A static magnetic field is provided by two pairs of Helmholtz coils mutually perpendicular and about 90 cm in diameter. The strength of the magnetic field is calibrated by using magnetic resonance signals of optically pumped Rb atoms. Figure 2 shows the frequency spectrum of the intensity fluctuation of transmitted light observed when the laser was tuned to the transition from the state F 1⁄4 1 in the ground state to the state F0 1⁄4 1 in the excited state by adjusting the driving current of the laser diode. Sharp resonance signals can be seen at the hyperfine splittings of K and K, 462 and 254MHz, respectively, on the background of broad noise spectrum. When a weak static magnetic field H0 is applied to the K vapor, the hyperfine spectra of K splits into several lines (the effective gyro-magnetic ratio of K is known to be 1⁄4 2 700 kHz/G). Figures 3(a) and 3(b) show the observed Zeeman hyperfine spectra of K for

Journal of the Physical Society of JapanApr 15, 20034 citations

Hyperfine interaction in the presence of a strong nonmonochromatic laser field

ARTUR K. EKERT, Wojciech Gawlik

Physics Letters AApr 1, 19874 citations

All-Optical Magnetometer Based on Resonant Excitation of Rubidium Atoms by Frequency Modulated Diode Laser Light

S. Cartaleva, Todor S. Karaulanov, Nikolay Petrov +6 more

Magnetic field and its gradient measurements based on coherent population trapping resonances at the D1 line of 87 Rb are performed by means of coupling two ground-state Zeeman sublevels belonging to different hyperfine levels to a common excited state.Two coherent laser fields with frequency difference of 6.8 GHz are used.They are produced by direct current modulation of a diode laser.The resonance splitting and broadening caused by the applied magnetic field is measured by scanning the laser modulation frequency around the ground-state hyperfine frequency.Magnetic field and its gradient measurements based on coherent population trapping resonances at the D1 line of 87 Rb are performed by means of coupling two ground-state Zeeman sublevels belonging to different hyperfine levels to a common excited state.Two coherent laser fields with frequency difference of 6.8 GHz are used.They are produced by direct current modulation of a diode laser.The resonance splitting and broadening caused by the applied magnetic field is measured by scanning the laser modulation frequency around the ground-state hyperfine frequency.

Acta Physica Polonica ANov 1, 20072 citations

Hyperfine spectroscopy of highly-excited atomic states based on atomic coherence

Shaozheng Jin, Yongqing Li, Min Xiao

Optics CommunicationsAug 1, 199528 citations

Hyperfine splitting of the 3 2 Sstate of Li7 measured using Stark spectroscopy of Rydberg states

G. D. Stevens, Chun-ho Iu, Sandra Williams +2 more

Precision measurements of Rydberg Stark levels of $^{7}\mathrm{Li}$ atoms are used to determine the 3 $^{2}$ S hyperfine separation, \ensuremath{\Delta} ${\mathit{E}}_{\mathit{h}\mathit{f}}$ (3 $^{2}$ S). Three diode lasers at \ensuremath{\lambda}=671 nm, 813 nm, and 633 nm excite $^{7}\mathrm{Li}$ atoms to n=15 sublevels in the presence of an electric field. Photoionization resonances at fields below the saddle point are used in conjunction with matrix diagonalization calculations to determine the binding energy of levels excited from each 3 $^{2}$ S hyperfine sublevel. The difference between the two fitted binding energies excited from 3 $^{2}$ S (F=1) and 3 $^{2}$ S (F=2) yields 189.36(43) MHz for \ensuremath{\Delta} ${\mathit{E}}_{\mathit{h}\mathit{f}}$ (3 $^{2}$ S ${;}^{7}$ Li).Precision measurements of Rydberg Stark levels of $^{7}\mathrm{Li}$ atoms are used to determine the 3 $^{2}$S hyperfine separation, \ensuremath{\Delta}${\mathit{E}}_{\mathit{h}\mathit{f}}$(3 $^{2}$S). Three diode lasers at \ensuremath{\lambda}=671 nm, 813 nm, and 633 nm excite $^{7}\mathrm{Li}$ atoms to n=15 sublevels in the presence of an electric field. Photoionization resonances at fields below the saddle point are used in conjunction with matrix diagonalization calculations to determine the binding energy of levels excited from each 3 $^{2}$S hyperfine sublevel. The difference between the two fitted binding energies excited from 3 $^{2}$S (F=1) and 3 $^{2}$S (F=2) yields 189.36(43) MHz for \ensuremath{\Delta}${\mathit{E}}_{\mathit{h}\mathit{f}}$(3 $^{2}$S${;}^{7}$Li).

Physical Review AApr 1, 199516 citations

Simple atomic systems in resonant laser fields

Mikhail L. Ter-Mikhaelyan

Uspekhi Fizicheskih NaukJan 1, 19978 citations

Precision measurements of Rydberg Stark levels of

^{7}\mathrm{Li}

atoms are used to determine the 3

^{2}

S hyperfine separation, \ensuremath{\Delta}

{\mathit{E}}_{\mathit{h}\mathit{f}}

^{2}

S). Three diode lasers at \ensuremath{\lambda}=671 nm, 813 nm, and 633 nm excite

^{7}\mathrm{Li}

atoms to n=15 sublevels in the presence of an electric field. Photoionization resonances at fields below the saddle point are used in conjunction with matrix diagonalization calculations to determine the binding energy of levels excited from each 3

^{2}

S hyperfine sublevel. The difference between the two fitted binding energies excited from 3

^{2}

S (F=1) and 3

^{2}

S (F=2) yields 189.36(43) MHz for \ensuremath{\Delta}

{\mathit{E}}_{\mathit{h}\mathit{f}}

^{2}

{;}^{7}

Li).