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

arXiv:1502.07187 · Optics Letters

Atomic Faraday filter with equivalent noise bandwidth less than 1 GHz

Mark A. Zentile, Daniel J. Whiting, James Keaveney, Charles S. Adams, Ifan G. Hughes

Published Apr 22, 2015• 71 citations
arXivHTMLPDF

Abstract

We demonstrate an atomic bandpass optical filter with an equivalent noise bandwidth less than 1 GHz using the D1 line in a cesium vapor. We use the ElecSus computer program to find optimal experimental parameters and find that, for important quantities, the cesium D1 line clearly outperforms other alkali metals on either D-lines. The filter simultaneously achieves a peak transmission of 77%, a passband of 310 MHz, and an equivalent noise bandwidth of 0.96 GHz, for a magnetic field of 45.3 G and a temperature of 68.0°C. Experimentally, the prediction from the model is verified. The experiment and theoretical predictions show excellent agreement.

DOI
10.1364/ol.40.002000

Related papers

Investigation of the temperature and magnetic field effect on the Cesium D1 atomic line filter characteristics

Mohammad Karami, Saed Golshan Khavas, Farrokh Sarreshtedari

Atomic spectral line filter is a narrow band pass optical filter which has many applications in quantum and laser systems. By engineering the system parameters like gas temperature and intensity of magnetic field, the filter with desired characteristics could be obtained. In this work, an atomic spectral line filter for Cesium D1 line (894.6nm) is implemented and characterized. The effect of system parameters on the filter transmission and its bandwidth is investigated. It is observed that by applying a magnetic field of 390 Gauss and adjusting the gas cell temperature on 40°C, a single peak filter with maximum filter transmission and FWHM of 0.24 GHz could be obtained.

Iranian Journal of Physics Research•May 1, 2022•0 citations

Ultranarrow Faraday rotation filter at the Rb D_1 line

Joanna A. Zielińska, Federica A. Beduini, Nicolas Godbout +1 more

We present a theoretical and experimental study of the ultranarrow bandwidth Faraday anomalous dispersion optical filter operating at the rubidium D1 line (795 nm). This atomic line gives better performance than other lines for key figures of merit, e.g., simultaneously 71% transmission, 445 MHz bandwidth, and 1.2 GHz equivalent-noise bandwidth.

arXiv:1110.2362•Optics Letters•Feb 8, 2012•91 citations

Filter Performance of a Cesium Faraday Optical Filter at 852 nm

Zhang Yun-Dong, Xiaoling Jia, Bi Yong +2 more

We have investigated a cesium Faraday filter at 852nm in relatively weak and strong magnetic fields, theoretically and experimentally. With a cesium cell of 0.02m length in an axial magnetic field of 0.06T, the line-centre operation has been achieved. The calculated peak transmission reached 99% with a full width at half maximum (FWHM) bandwidth of only 3.9 GHz. The measured FWHM bandwidth of the filter is 3.29 GHz, which is in general agreement with the theoretical result.

Chinese Physics Letters•May 28, 2002•5 citations

Theoretical model for a Faraday anomalous dispersion optical filter

B. Yin, Thomas M. Shay

A model for the Faraday anomalous dispersion optical filter is presented. Our model predicts a bandwidth of 0.6 GHz and a transmission peak of 0.98 for a filter operating on the Cs (D(2)) line. The model includes hyperfine effects and is valid for arbitrary magnetic fields.

Optics Letters•Oct 15, 1991•90 citations

Ultranarrow line filtering using a Cs Faraday filter at 852 nm

J. Menders, K. Benson, Scott H. Bloom +2 more

To achieve quantum-noise-limited performance, background-limited laser receivers require narrow-band optical filters. We measured and modeled the ultranarrow-band transmission spectrum of a Cs Faraday filter at 852 nm. The transmission spectrum consisted of passbands on either side of the 6 (2)S((1/2))-6 (2)P(3/2) hyperfine doublet lines, making a total of four. The passbands may be simple peaks or highly modulated, depending on the operating parameters. We observed peaked passbands of near-unity transmission with a 0.6-GHz bandwidth and modulated bands with features as sharp as 100 MHz. Excellent agreement with our calculations at 852 nm allows us to predict confidently a 0.7-GHz transmission band for Cs at 455 nm.

Optics Letters•Jun 1, 1991•119 citations

Lithium Faraday filter: some like it hot

Maximilian Luka, Yijun Wang, Denis Uhland +1 more

Magnetically induced rotation of linearly polarized light near an atomic resonance, combined with Doppler-broadened absorption windows, enables narrowband transmission of optical frequencies. A narrowband (2.2 GHz) lithium vapor Faraday filter at about 671 nm is investigated experimentally and theoretically. The resulting Faraday filter transmittance is demonstrated using a lithium heat pipe oven under longitudinal magnetic fields ranging from 0 to 300 G. The optimized lithium Faraday filter exhibits the peak transmittance of 82% with commonly chosen optimal parameters around the 7 Li transitions center. The lithium D 1 - and D 2 -transitions are only 10 GHz apart, and temperature broadening leads to an overlap of the isotopes’ D -lines. Thus, the applied theoretical model needs to consider both transitions simultaneously. For this purpose, we extended an existing Python library (ElecSus), which now allows for the calculation of the atomic susceptibilities of lithium.

arXiv:2510.11859•Optics Letters•Dec 3, 2025•0 citations
We demonstrate an atomic bandpass optical filter with an equivalent noise bandwidth less than 1 GHz using the D1 line in a cesium vapor. We use the ElecSus computer program to find optimal experimental parameters and find that, for important quantities, the cesium D1 line clearly outperforms other alkali metals on either D-lines. The filter simultaneously achieves a peak transmission of 77%, a passband of 310 MHz, and an equivalent noise bandwidth of 0.96 GHz, for a magnetic field of 45.3 G and a temperature of 68.0°C. Experimentally, the prediction from the model is verified. The experiment and theoretical predictions show excellent agreement.
Atomic spectral line filter is a narrow band pass optical filter which has many applications in quantum and laser systems. By engineering the system parameters like gas temperature and intensity of magnetic field, the filter with desired characteristics could be obtained. In this work, an atomic spectral line filter for Cesium D1 line (894.6nm) is implemented and characterized. The effect of system parameters on the filter transmission and its bandwidth is investigated. It is observed that by applying a magnetic field of 390 Gauss and adjusting the gas cell temperature on 40°C, a single peak filter with maximum filter transmission and FWHM of 0.24 GHz could be obtained.
To achieve quantum-noise-limited performance, background-limited laser receivers require narrow-band optical filters. We measured and modeled the ultranarrow-band transmission spectrum of a Cs Faraday filter at 852 nm. The transmission spectrum consisted of passbands on either side of the 6 (2)S((1/2))-6 (2)P(3/2) hyperfine doublet lines, making a total of four. The passbands may be simple peaks or highly modulated, depending on the operating parameters. We observed peaked passbands of near-unity transmission with a 0.6-GHz bandwidth and modulated bands with features as sharp as 100 MHz. Excellent agreement with our calculations at 852 nm allows us to predict confidently a 0.7-GHz transmission band for Cs at 455 nm.
Magnetically induced rotation of linearly polarized light near an atomic resonance, combined with Doppler-broadened absorption windows, enables narrowband transmission of optical frequencies. A narrowband (2.2 GHz) lithium vapor Faraday filter at about 671 nm is investigated experimentally and theoretically. The resulting Faraday filter transmittance is demonstrated using a lithium heat pipe oven under longitudinal magnetic fields ranging from 0 to 300 G. The optimized lithium Faraday filter exhibits the peak transmittance of 82% with commonly chosen optimal parameters around the 7 Li transitions center. The lithium D 1 - and D 2 -transitions are only 10 GHz apart, and temperature broadening leads to an overlap of the isotopes’ D -lines. Thus, the applied theoretical model needs to consider both transitions simultaneously. For this purpose, we extended an existing Python library (ElecSus), which now allows for the calculation of the atomic susceptibilities of lithium.