Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

In situ Doppler-free spectroscopy with pulsed optical fields

Yuxin Wang, Zhiyue Zheng, Qiuxin Zhang, Yonglang Lai, Zongqi Ge, Tianyi Wang, Liangyu Ding, Vasilii N. Smirnov, Ilya A. Semerikov, Shuaining Zhang, Wei Zhang, Xiang Zhang

Published Aug 12, 2025• 0 citations
Publisher

Abstract

We propose a novel pulsed optical method based on saturated absorption spectroscopy, where the pump beam is periodically switched on and off using pulse amplitude modulation. This periodic alternation enables time-division multiplexing of the same probe beam into both probe and reference signals, achieving differential Doppler-free spectroscopy with a deterministic zero background. This method effectively mitigates Doppler broadening and common-mode optical noise by addressing disturbances such as nonuniform background absorption and environmental noise, thereby offering enhanced accuracy and robustness. Using this technique, we measured the transition frequency of ${\mathrm{Yb}}^{+}$ isotopes in the $^{2}S_{1/2}\ensuremath{\rightarrow}^{2}P_{1/2}$ transition. By employing an error signal derived from the dispersive signal of $^{174}\mathrm{Yb}^{+}$, we achieved efficient stabilization of a 369.5-nm ultraviolet diode laser, demonstrating a frequency stability of $3\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}$ (26 kHz) over a 1500-s averaging period and a locking point standard deviation of 850 kHz sustained over 10 days. Furthermore, we report the first in situ observation of Doppler-free Zeeman sublevel spectra in a hot ion system, highlighting the precision of this method and its potential application in measuring magnetic field gradients.

DOI
10.1103/w8tl-stvh

Related papers

Frequency stabilization of a 369 nm diode laser by nonlinear spectroscopy of Ytterbium ions in a discharge

Michael W. Lee, Marie Claire Jarratt, Christian D. Marciniak +1 more

We demonstrate stabilization of an ultraviolet diode laser via Doppler-free spectroscopy of Ytterbium ions in a discharge. Our technique employs polarization spectroscopy, which produces a natural dispersive lineshape whose zero-crossing is largely immune to environmental drifts, making this signal an ideal absolute frequency reference for Yb+ ion trapping experiments. We stabilize an external-cavity diode laser near 369 nm for cooling Yb+ ions, using amplitude modulated polarization spectroscopy and a commercial PID feedback system. We achieve stable, low-drift locking with a standard deviation of measured laser frequency ∼ 400 kHz over 10 minutes, limited by the instantaneous linewidth of the diode laser. These results and the simplicity of our optical setup makes our approach attractive for stabilization of laser sources in atomic physics applications.

arXiv:1402.1248•Optics Express•Mar 19, 2014•18 citations

Differential Detection of Doppler-Free Spectroscopy with Modulation Transfer

Tenghui Yang, Peter Yun

Combined with the modulation transfer method, we successfully observe a frequency discriminating signal with improved signal-to-noise ratio (SNR) in the scheme of differential detection of Doppler-free spectroscopy. In our previous counter-propagated pump-probe scheme, two orthogonal polarization components of the probe beam constrictive and destructive interact with dark state prepared by the pump beam, respectively. This led to simultaneous enhanced absorption and transmission by detecting the parallel and perpendicular polarization components of the transmitted probe beam. In this presentation, we add modulation to the pump beam, error signals are obtained by synchronous demodulating the probe beam transmission with the help of the four-wave mixing process in the light-atom interaction system. Our method not only boost the SNR of the error signal of differential detection signal compared to the traditional one, but also mitigate atomic resonance broadening and shift induced by direct modulation of the probe beam thanks to the modulation transfer spectroscopy. This new method may find applications in high-performance optical reference, high-resolution spectroscopy and so on.

Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS)•May 12, 2025•0 citations

Full differential spectroscopy for high-stability vapor cell optical frequency reference

Tenghui Yang, Peter Yun, Rodolphe Boudot +3 more

We propose and experimentally demonstrate a spectroscopic method, named full differential spectroscopy, that uses a single laser beam in retroreflected configuration to manipulate atomic dark states in a vapor cell. Conventional Doppler-free spectroscopy often suffers from limited performance due to the Doppler-broaden background. Here we show that by selectively coupling or decoupling the probe’s polarization components with the pump-induced dark state, we can simultaneously obtain both Doppler-free electromagnetically induced transparency and absorption. A differential signal, with enhanced Doppler-free amplitude and highly suppressed background and noise, is thus obtained. We systematically characterize how polarization angle and light power affect the resonance and noise properties. Using this approach, we stabilize a laser to a rubidium vapor cell, achieving a fractional frequency stability of 1.2 × 10 −13 at 1 s. These results demonstrate a simple, robust route to high-performance optical frequency references and may also benefit quantum sensing or high-resolution spectroscopy.

Communications Physics•Sep 23, 2026•0 citations

Enhanced absorption in Doppler-free spectroscopy of the Rb atom D 1 line with monochromatic light: Application to laser-frequency stabilization

Peter Yun, Rodolphe Boudot, Qiang Hao +1 more

The detection of narrow and high-amplitude optical resonances in atomic cells is of crucial importance for the development of compact and high-stability lasers or vapor-cell optical references. In this work, using monochromatic light and appropriate polarization settings for the counterpropagating pump and probe beams, we demonstrate the detection of enhanced-absorption sub-Doppler resonances on the ${D}_{1}$ line of the $\mathrm{Rb}$ atom. We report a theoretical model showing that the Zeeman coherence induced between magnetic sublevels---especially in the $F\ensuremath{\rightarrow}{F}^{\ensuremath{'}}=F\ensuremath{-}1$ systems, with $F$ and ${F}^{\ensuremath{'}}$ being the hyperfine quantum numbers of the ground and excited states, respectively---plays a key role in the observed enhanced-absorption process. The theoretically predicted behavior matches the experimental observations well. The impact of light polarization, laser intensity, magnetic field, and cell temperature on the Doppler-free resonance features is experimentally investigated. For application, two identical diode lasers are frequency-stabilized onto enhanced-absorption sub-Doppler resonances. The fractional frequency stability of the laser beatnote is measured to be $1.8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}$ at $1\phantom{\rule{0.1em}{0ex}}\mathrm{s}$ and $8.4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}$ at ${10}^{4}\phantom{\rule{0.1em}{0ex}}\mathrm{s}$. These results demonstrate the potential of this scheme for the implementation of a compact or even chip-scale optical frequency reference, which might find applications in instrumentation, navigation, and metrology.

Physical Review Applied•Mar 25, 2025•4 citations

Saturated absorption spectroscopy with a Zeeman shift

Un Yob Shim, Jong-An Kim, W. Jhe

Recently a new type of spectroscopy using Zeeman shift has been developed, which aims for a large recapture range by making a dispersive-like signal obtained from the subtraction of two different circularly polarized Doppler-broadened absorption signals in the presence of a magnetic field (order of 100 G). We would like to propose another method for stabilizing a diode laser frequency onto an atomic frequency with a small tunable range in the presence of small longitudinal magnetic field (order of Gauss). A solid state diode laser is preferred as it is a good light source. Our technique has the advantages of cancellation of frequency fluctuation over side-locking and no need for phase-sensitive detection and frequency modulation over peak-locking. A subtracted SAS signal and the blocking signal are displayed on one photodiode.

Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR)•Jan 20, 2003•0 citations

BACKGOUND-FREE SATURATION SPECTROSCOPY WITH A FREQUENCY-OFFSET PUMP

James Snyder, Rama K. Raj, D. Blöch +1 more

We report the development of a simple method for eliminating coherent background noise and fluctuations from saturation spectroscopy signals. With this technique, which utilizes a traveling-wave acousto-optic modulator to simultaneously frequency-shift and modulate the saturating beam, we have routinely observed zero background, Doppler-free saturation resonances in the $I_{2}$ at 514.5 nm. With a low-noise laser or high pump modulation frequency, we have achieved detection sensitivity approaching the fundamental quantum limit.

•Jan 1, 1980•0 citations
We propose a novel pulsed optical method based on saturated absorption spectroscopy, where the pump beam is periodically switched on and off using pulse amplitude modulation. This periodic alternation enables time-division multiplexing of the same probe beam into both probe and reference signals, achieving differential Doppler-free spectroscopy with a deterministic zero background. This method effectively mitigates Doppler broadening and common-mode optical noise by addressing disturbances such as nonuniform background absorption and environmental noise, thereby offering enhanced accuracy and robustness. Using this technique, we measured the transition frequency of Yb+{\mathrm{Yb}}^{+}Yb+ isotopes in the 2S1/2\ensuremath→2P1/2^{2}S_{1/2}\ensuremath{\rightarrow}^{2}P_{1/2}2S1/2​\ensuremath→2P1/2​ transition. By employing an error signal derived from the dispersive signal of 174Yb+^{174}\mathrm{Yb}^{+}174Yb+, we achieved efficient stabilization of a 369.5-nm ultraviolet diode laser, demonstrating a frequency stability of 3\ifmmode×\else\texttimes\fi10\ensuremath−113\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}11}3\ifmmode×\else\texttimes\fi10\ensuremath−11 (26 kHz) over a 1500-s averaging period and a locking point standard deviation of 850 kHz sustained over 10 days. Furthermore, we report the first in situ observation of Doppler-free Zeeman sublevel spectra in a hot ion system, highlighting the precision of this method and its potential application in measuring magnetic field gradients.
We demonstrate stabilization of an ultraviolet diode laser via Doppler-free spectroscopy of Ytterbium ions in a discharge. Our technique employs polarization spectroscopy, which produces a natural dispersive lineshape whose zero-crossing is largely immune to environmental drifts, making this signal an ideal absolute frequency reference for Yb+ ion trapping experiments. We stabilize an external-cavity diode laser near 369 nm for cooling Yb+ ions, using amplitude modulated polarization spectroscopy and a commercial PID feedback system. We achieve stable, low-drift locking with a standard deviation of measured laser frequency ∼ 400 kHz over 10 minutes, limited by the instantaneous linewidth of the diode laser. These results and the simplicity of our optical setup makes our approach attractive for stabilization of laser sources in atomic physics applications.
Combined with the modulation transfer method, we successfully observe a frequency discriminating signal with improved signal-to-noise ratio (SNR) in the scheme of differential detection of Doppler-free spectroscopy. In our previous counter-propagated pump-probe scheme, two orthogonal polarization components of the probe beam constrictive and destructive interact with dark state prepared by the pump beam, respectively. This led to simultaneous enhanced absorption and transmission by detecting the parallel and perpendicular polarization components of the transmitted probe beam. In this presentation, we add modulation to the pump beam, error signals are obtained by synchronous demodulating the probe beam transmission with the help of the four-wave mixing process in the light-atom interaction system. Our method not only boost the SNR of the error signal of differential detection signal compared to the traditional one, but also mitigate atomic resonance broadening and shift induced by direct modulation of the probe beam thanks to the modulation transfer spectroscopy. This new method may find applications in high-performance optical reference, high-resolution spectroscopy and so on.
We propose and experimentally demonstrate a spectroscopic method, named full differential spectroscopy, that uses a single laser beam in retroreflected configuration to manipulate atomic dark states in a vapor cell. Conventional Doppler-free spectroscopy often suffers from limited performance due to the Doppler-broaden background. Here we show that by selectively coupling or decoupling the probe’s polarization components with the pump-induced dark state, we can simultaneously obtain both Doppler-free electromagnetically induced transparency and absorption. A differential signal, with enhanced Doppler-free amplitude and highly suppressed background and noise, is thus obtained. We systematically characterize how polarization angle and light power affect the resonance and noise properties. Using this approach, we stabilize a laser to a rubidium vapor cell, achieving a fractional frequency stability of 1.2 × 10 −13 at 1 s. These results demonstrate a simple, robust route to high-performance optical frequency references and may also benefit quantum sensing or high-resolution spectroscopy.
The detection of narrow and high-amplitude optical resonances in atomic cells is of crucial importance for the development of compact and high-stability lasers or vapor-cell optical references. In this work, using monochromatic light and appropriate polarization settings for the counterpropagating pump and probe beams, we demonstrate the detection of enhanced-absorption sub-Doppler resonances on the D1{D}_{1}D1​ line of the Rb\mathrm{Rb}Rb atom. We report a theoretical model showing that the Zeeman coherence induced between magnetic sublevels---especially in the $F\ensuremath{\rightarrow}{F}^{\ensuremath{'}}=F\ensuremath{-}1$ systems, with FFF and ${F}^{\ensuremath{'}}$ being the hyperfine quantum numbers of the ground and excited states, respectively---plays a key role in the observed enhanced-absorption process. The theoretically predicted behavior matches the experimental observations well. The impact of light polarization, laser intensity, magnetic field, and cell temperature on the Doppler-free resonance features is experimentally investigated. For application, two identical diode lasers are frequency-stabilized onto enhanced-absorption sub-Doppler resonances. The fractional frequency stability of the laser beatnote is measured to be $1.8\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}$ at 1s1\phantom{\rule{0.1em}{0ex}}\mathrm{s}1s and $8.4\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}$ at 104s{10}^{4}\phantom{\rule{0.1em}{0ex}}\mathrm{s}104s. These results demonstrate the potential of this scheme for the implementation of a compact or even chip-scale optical frequency reference, which might find applications in instrumentation, navigation, and metrology.
Recently a new type of spectroscopy using Zeeman shift has been developed, which aims for a large recapture range by making a dispersive-like signal obtained from the subtraction of two different circularly polarized Doppler-broadened absorption signals in the presence of a magnetic field (order of 100 G). We would like to propose another method for stabilizing a diode laser frequency onto an atomic frequency with a small tunable range in the presence of small longitudinal magnetic field (order of Gauss). A solid state diode laser is preferred as it is a good light source. Our technique has the advantages of cancellation of frequency fluctuation over side-locking and no need for phase-sensitive detection and frequency modulation over peak-locking. A subtracted SAS signal and the blocking signal are displayed on one photodiode.
We report the development of a simple method for eliminating coherent background noise and fluctuations from saturation spectroscopy signals. With this technique, which utilizes a traveling-wave acousto-optic modulator to simultaneously frequency-shift and modulate the saturating beam, we have routinely observed zero background, Doppler-free saturation resonances in the I2I_{2}I2​ at 514.5 nm. With a low-noise laser or high pump modulation frequency, we have achieved detection sensitivity approaching the fundamental quantum limit.