We demonstrate Ramsey spectroscopy with cold 87 Rb atoms via a two-photon Raman process. One laser beam has a cross-over resonant frequency on the 85 Rb transition and the other beam has a 6.8 GHz shifted frequency. These two laser beams fulfill the two-photon Raman resonance condition, which involves a single-photon detuning of −2.6 GHz. By implementing these two lasers on cold 87 Rb atoms, we demonstrate Ramsey spectroscopy with an interrogation time of the intermediate state by using π /2 Raman pulses. In our laser system, we can change the single-photon detuning to 1.2, 4.2 or −5.6 GHz by changing the 85 Rb transition line used as a locking signal and an injected sideband. The laser system that directly uses resonant light on isotope atoms will be described in this paper.We demonstrate Ramsey spectroscopy with cold 87 Rb atoms via a two-photon Raman process. One laser beam has a cross-over resonant frequency on the 85 Rb transition and the other beam has a 6.8 GHz shifted frequency. These two laser beams fulfill the two-photon Raman resonance condition, which involves a single-photon detuning of −2.6 GHz. By implementing these two lasers on cold 87 Rb atoms, we demonstrate Ramsey spectroscopy with an interrogation time of the intermediate state by using π /2 Raman pulses. In our laser system, we can change the single-photon detuning to 1.2, 4.2 or −5.6 GHz by changing the 85 Rb transition line used as a locking signal and an injected sideband. The laser system that directly uses resonant light on isotope atoms will be described in this paper.

Journal of the Korean Physical SocietyMar 1, 20140 citations

High-Resolution Spectroscopy in Fast Atomic Beams

R. Neugart, S. L. Kaufman, W. Klempt +3 more

Springer series in optical sciences/SPringer series in optical sciencesJan 1, 19775 citations

Speed-adjustable atomic beam of metastable helium for precision measurement

J.-J. Chen, Yu Sun, Jin-Lu Wen +1 more

A bright beam of metastable helium atoms is useful in various studies. Laser spectroscopy of helium in an atomic beam can provide a determination of the fine-structure constant and the nuclear charge radius, towards a test of quantum electrodynamics (QED). In these measurements, it is necessary to control not only the internal quantum state but also the translation motion of the helium atom. Here we present a setup producing an intense and speed-adjustable continuous beam of helium atoms. By using a combination of laser cooling, focusing, and deflection, helium atoms are prepared at the single quantum state of ${2}^{\phantom{\rule{0.16em}{0ex}}3}{S}_{1}$ ( $m=0$ ), with a very narrow distribution of the longitudinal speed ($\ensuremath{\delta}{v}_{z}<\ifmmode\pm\else\textpm\fi{}4.5$ m/s). At the same time, we obtain a flux of $1.8\ifmmode\times\else\texttimes\fi{}{10}^{13}$ (atoms/s)/sr with a fractional fluctuation below 0.02%. The atomic-beam quality was investigated by laser spectroscopy, indicating a considerable improvement over those used in previous helium precision-spectroscopy measurements.A bright beam of metastable helium atoms is useful in various studies. Laser spectroscopy of helium in an atomic beam can provide a determination of the fine-structure constant and the nuclear charge radius, towards a test of quantum electrodynamics (QED). In these measurements, it is necessary to control not only the internal quantum state but also the translation motion of the helium atom. Here we present a setup producing an intense and speed-adjustable continuous beam of helium atoms. By using a combination of laser cooling, focusing, and deflection, helium atoms are prepared at the single quantum state of ${2}^{\phantom{\rule{0.16em}{0ex}}3}{S}_{1}$ ($m=0$), with a very narrow distribution of the longitudinal speed ($\ensuremath{\delta}{v}_{z}<\ifmmode\pm\else\textpm\fi{}4.5$ m/s). At the same time, we obtain a flux of $1.8\ifmmode\times\else\texttimes\fi{}{10}^{13}$ (atoms/s)/sr with a fractional fluctuation below 0.02%. The atomic-beam quality was investigated by laser spectroscopy, indicating a considerable improvement over those used in previous helium precision-spectroscopy measurements.

Physical Review AMay 11, 20209 citations

Photon-burst method in high-resolution laser spectroscopy

D. A. Lewis, J. F. Tonn, S. L. Kaufman +1 more

The sensitivity of high-resolution fluorescence spectroscopy has been enhanced by the detection of bursts of photons from single atoms crossing a laser beam. A tunable cw laser beam intersected a well-collimated atomic beam at right angles, and the fluorescent light was detected by an ellipsoidal collector and a photomultiplier. The passage of an atom through the beam was identified with a burst of detected photon pulses, which could be differentiated easily from the random background. For increasing burst multiplicity the spectra show improved background suppression and also significant peak narrowing. High-resolution spectra were obtained with as few as 10 atoms/sec crossing the laser beam. Statistical predictions for the case of transit-time limited signals are calculated and compared with results obtained for the Na 5890-\AA{} and Ba 5535-\AA{} transitions.The sensitivity of high-resolution fluorescence spectroscopy has been enhanced by the detection of bursts of photons from single atoms crossing a laser beam. A tunable cw laser beam intersected a well-collimated atomic beam at right angles, and the fluorescent light was detected by an ellipsoidal collector and a photomultiplier. The passage of an atom through the beam was identified with a burst of detected photon pulses, which could be differentiated easily from the random background. For increasing burst multiplicity the spectra show improved background suppression and also significant peak narrowing. High-resolution spectra were obtained with as few as 10 atoms/sec crossing the laser beam. Statistical predictions for the case of transit-time limited signals are calculated and compared with results obtained for the Na 5890-\AA{} and Ba 5535-\AA{} transitions.

Physical Review AApr 1, 197924 citations

The Spectroscopy of Highly Excited Atoms

Daniel Kleppner

Springer eBooksJan 1, 19798 citations

{2}^{\phantom{\rule{0.16em}{0ex}}3}{S}_{1}

(

m=0

), with a very narrow distribution of the longitudinal speed ($\ensuremath{\delta}{v}_{z}<\ifmmode\pm\else\textpm\fi{}4.5$ m/s). At the same time, we obtain a flux of $1.8\ifmmode\times\else\texttimes\fi{}{10}^{13}$ (atoms/s)/sr with a fractional fluctuation below 0.02%. The atomic-beam quality was investigated by laser spectroscopy, indicating a considerable improvement over those used in previous helium precision-spectroscopy measurements.