Abstract It is common for senior physics students at many universities to perform optical pumping experiments using a rubidium cell in an integrated apparatus. Such experiments provide an encounter with atomic structure in the context of a standard technique of modern atomic physics. Typically, students investigate radiofrequency resonances between Zeeman levels and measure hyperfine splitting. Despite its pivotal role in aligning the apparatus the so-called zero-field resonance is usually not investigated in such experiments. However it is instructive to look more closely at this phenomenon. We show that it is a consequence of a residual transverse magnetic field that is the result of the inability to align precisely the optical axis of the apparatus in the local N – S direction. The measured width and depth of the resonance-like minimum in transmission is found to be consistent with a very small relaxation rate for the rubidium atoms. In an appendix we show further that the measurements compare well with theory for the Hanle effect in the ground state for an arbitrary magnetic field direction relative to the optical axis of the experiment.Abstract It is common for senior physics students at many universities to perform optical pumping experiments using a rubidium cell in an integrated apparatus. Such experiments provide an encounter with atomic structure in the context of a standard technique of modern atomic physics. Typically, students investigate radiofrequency resonances between Zeeman levels and measure hyperfine splitting. Despite its pivotal role in aligning the apparatus the so-called zero-field resonance is usually not investigated in such experiments. However it is instructive to look more closely at this phenomenon. We show that it is a consequence of a residual transverse magnetic field that is the result of the inability to align precisely the optical axis of the apparatus in the local N – S direction. The measured width and depth of the resonance-like minimum in transmission is found to be consistent with a very small relaxation rate for the rubidium atoms. In an appendix we show further that the measurements compare well with theory for the Hanle effect in the ground state for an arbitrary magnetic field direction relative to the optical axis of the experiment.

European Journal of PhysicsJul 10, 20200 citations

Multiphoton resonance in rubidium vapor under hyperfine optical pumping

V. N. Gutsaki, V. É. Dindarov, V. S. Zholnerov +2 more

Optics and SpectroscopyJan 1, 19860 citations

Coherent population dynamics in rubidium atoms excited by resonant 0π pulses

Ticijana Ban, Damir Aumiler, Silvije Vdović +3 more

We investigate the time dynamics of a four-level rubidium atomic system excited by a train of $0\ensuremath{\pi}$ pulses. Resonant $0\ensuremath{\pi}$ pulse shaping is achieved by propagation of weak femtosecond pulses through rubidium vapor and characterized using frequency-resolved optical gating and within the linear dispersion theory. The excitation of the Rb atoms by $0\ensuremath{\pi}$ pulse train is studied experimentally by modified direct frequency comb spectroscopy and theoretically within the density-matrix approach. We show that accumulation of populations and coherences, as typical pulse train excitation effects, strongly depend on the strength of the resonant $0\ensuremath{\pi}$ pulse shaping. Stronger pulse shaping reduces the coherent accumulation effects, eventually leading to the disappearance of the velocity selective optical pumping observed in the frequency domain.We investigate the time dynamics of a four-level rubidium atomic system excited by a train of $0\ensuremath{\pi}$ pulses. Resonant $0\ensuremath{\pi}$ pulse shaping is achieved by propagation of weak femtosecond pulses through rubidium vapor and characterized using frequency-resolved optical gating and within the linear dispersion theory. The excitation of the Rb atoms by $0\ensuremath{\pi}$ pulse train is studied experimentally by modified direct frequency comb spectroscopy and theoretically within the density-matrix approach. We show that accumulation of populations and coherences, as typical pulse train excitation effects, strongly depend on the strength of the resonant $0\ensuremath{\pi}$ pulse shaping. Stronger pulse shaping reduces the coherent accumulation effects, eventually leading to the disappearance of the velocity selective optical pumping observed in the frequency domain.

Physical Review AAug 28, 20099 citations

Nonlinear four-wave mixing using electromagnetically induced transparency in rubidium atoms

Yongqing Li, Min Xiao

Quantum Electronics and Laser Science ConferenceMay 22, 19950 citations

Thirteen pump-probe resonances of the sodium D1 line

Vincent Wong, Robert W. Boyd, Carlos R. Stroud +2 more

We present the results of a pump-probe laser spectroscopic investigation of the Doppler-broadened sodium $D1$ resonance line. We find 13 resonances in the resulting spectra. These observations are well described by the numerical predictions of a four-level atomic model of the hyperfine structure of the sodium $D1$ line. We also find that many, but not all, of these features can be understood in terms of processes originating in a two-level or three-level subset of the full four-level model. The processes we observed include forward near-degenerate four-wave mixing and saturation in a two-level system, difference-frequency crossing and nondegenerate four-wave mixing in a three-level V system, electromagnetically induced transparency and optical pumping in a three-level lambda system, cross-transition resonance in a four-level double-lambda system, and conventional optical pumping. Most of these processes lead to sub-Doppler or even subnatural linewidths. The dependence of these resonances on the pump intensity and pump detuning from atomic resonance are also studied.We present the results of a pump-probe laser spectroscopic investigation of the Doppler-broadened sodium $D1$ resonance line. We find 13 resonances in the resulting spectra. These observations are well described by the numerical predictions of a four-level atomic model of the hyperfine structure of the sodium $D1$ line. We also find that many, but not all, of these features can be understood in terms of processes originating in a two-level or three-level subset of the full four-level model. The processes we observed include forward near-degenerate four-wave mixing and saturation in a two-level system, difference-frequency crossing and nondegenerate four-wave mixing in a three-level V system, electromagnetically induced transparency and optical pumping in a three-level lambda system, cross-transition resonance in a four-level double-lambda system, and conventional optical pumping. Most of these processes lead to sub-Doppler or even subnatural linewidths. The dependence of these resonances on the pump intensity and pump detuning from atomic resonance are also studied.

Physical Review AJul 8, 200333 citations

We present the results of a pump-probe laser spectroscopic investigation of the Doppler-broadened sodium

D1

resonance line. We find 13 resonances in the resulting spectra. These observations are well described by the numerical predictions of a four-level atomic model of the hyperfine structure of the sodium

D1

line. We also find that many, but not all, of these features can be understood in terms of processes originating in a two-level or three-level subset of the full four-level model. The processes we observed include forward near-degenerate four-wave mixing and saturation in a two-level system, difference-frequency crossing and nondegenerate four-wave mixing in a three-level V system, electromagnetically induced transparency and optical pumping in a three-level lambda system, cross-transition resonance in a four-level double-lambda system, and conventional optical pumping. Most of these processes lead to sub-Doppler or even subnatural linewidths. The dependence of these resonances on the pump intensity and pump detuning from atomic resonance are also studied.