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Related papers: Sub-Doppler Double-Resonance Spectroscopy of Metha…

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We report a direct measurement of the 0-1 R(0) vibrational transition frequency in ground-state hydrogen deuteride (HD) using infrared-ultraviolet double resonance spectroscopy in a molecular beam. Ground-state molecules are vibrationally…

Atomic Physics · Physics 2020-07-14 Arthur Fast , Samuel A. Meek

A tunable diode laser spectrometer has been employed to examine the overtone absorption lines of $^{12}$CH$_4$ in the region around 12780 cm$^{-1}$ (780 nm) at room temperature. The spectrometer sources are commercially available tunable…

Chemical Physics · Physics 2022-02-10 A. Lucchesini

Direct frequency-comb spectroscopy is used to probe the absolute frequencies of $6S_{1/2}$-$8S_{1/2}$ two-photon transitions of atomic cesium in hot vapor environment. By utilizing the coherent control method of temporally splitting the…

Atomic Physics · Physics 2018-01-15 Kyung-tae Kim , Jaewook Ahn

Dual-comb spectroscopy is emerging as one of the most appealing applications of mid-infrared frequency combs for high-resolution molecular spectroscopy, as it leverages on the unique coherence properties of frequency combs combined with the…

We propose a new Fourier-transform spectroscopy technique based on the rotational Doppler effect. The technique offers an application for optical vortex frequency combs, where each frequency component carries a unique amount of orbital…

Optics · Physics 2024-10-28 Santeri Larnimaa , Markku Vainio

Photonic analog to digital conversion offers promise to overcome the signal-to-noise ratio (SNR) and sample rate trade-off in conventional analog to digital converters (ADCs), critical for modern digital communications and signal analysis.…

Signal Processing · Electrical Eng. & Systems 2019-09-09 Callum Deakin , Zhixin Liu

Acquisition of laser frequency with high resolution under continuous and abrupt tuning conditions is important for sensing, spectroscopy and communications. Here, a single microresonator provides rapid and broad-band measurement of…

We demonstrate the use of a femtosecond frequency comb to coherently drive stimulated Raman transitions between terahertz-spaced atomic energy levels. More specifically, we address the $3d~^2D_{3/2}$ and $3d~^2D_{5/2}$ fine structure levels…

Quantum Physics · Physics 2018-06-21 Cyrille Solaro , Steffen Meyer , Karin Fisher , Michael V. DePalatis , Michael Drewsen

We describe the design, fabrication, integration and characterization of a prototype superconducting filter bank with transition edge sensor readout designed to explore millimetre-wave detection at frequencies in the range 40 to 65 GHz.…

Instrumentation and Detectors · Physics 2020-07-15 D. J. Goldie , C. N. Thomas , S. Withington , A. Orlando , R. Sudiwala , P. Hargrave , P. K. Dongre

We report precision atmospheric spectroscopy of $CO_2$ using a laser heterodyne radiometer (LHR) calibrated with an optical frequency comb. Using the comb-calibrated LHR, we record spectra of atmospheric $CO_2$ near 1572.33 nm with a…

Optics · Physics 2023-10-03 Ryan K. Cole , Connor Fredrick , Newton H. Nguyen , Scott A. Diddams

Millimetre-wave observations represent an important tool for Cosmology studies. The Line Intensity Mapping (LIM) technique has been proposed to map in three dimensions the specific intensity due to line (e.g. [CII], CO) emission, for…

Instrumentation and Methods for Astrophysics · Physics 2023-08-29 Usasi Chowdhury , Florence Levy-Bertrand , Martino Calvo , Johannes Goupy , Alessandro Monfardini

We report the first experiments on the high pressure phonon spectra of transition-metal nitrides HfN, ZrN, and NbN, obtained by Raman scattering measurements. Two pronounced bands, which are related to the acoustic part at low frequency…

The broadband, coherent nature of narrow-linewidth fiber frequency combs is exploited to measure the full complex spectrum of a molecular gas through multi-heterodyne spectroscopy. We measure the absorption and phase shift experienced by…

Optics · Physics 2009-11-13 Ian Coddington , William C. Swann , Nathan R. Newbury

Astronomical spectrographs require frequency calibration through sources like hollow-cathode lamps or absorption-gas cells. Laser frequency combs (LFCs) provide highest accuracy but are facing operational challenges. We aim to provide a…

Instrumentation and Methods for Astrophysics · Physics 2024-09-05 Ansgar Reiners , Michael Debus , Sebastian Schäfer , Eberhard Tiemann , Mathias Zechmeister

We demonstrate ultra-broadband optoelectronic mixing of frequency combs that provides phase-coherent detection of a repetition frequency up to 500 GHz, using a high-speed modified uni-traveling carrier (MUTC) photodiode. Nonlinear…

Optics · Physics 2024-10-30 Jizhao Zang , Jesse S. Morgan , Andreas Beling , Scott B. Papp

Frequency combs based on nonlinear-optical phenomena in integrated photonics are a versatile light source that can explore new applications, including frequency metrology, optical communications, and sensing. We demonstrate robust…

Two-dimensional capacitively coupled radio frequency discharge in methane is simulated by PIC-MCC method. The results were obtained in pressure range 50-300 mTorr and voltage range 40-180 V for discharge frequency 13.56 MHz. The electron…

Plasma Physics · Physics 2009-11-10 A L Alexandrov , I V Schweigert

We performed a second-order spontaneous parametric down-conversion (SPDC) experiment in a Type II phase-matched KTiOPO4 crystal pumped at 532 nm giving birth to a signal beam at 1037 nm and an idler one at 1092 nm along the x-axis of the…

Quantum Physics · Physics 2025-02-10 Julien Bertrand , Véronique Boutou , Benoît Boulanger

We report on precision spectroscopy of the 6s$^2$ $^1$S$_0\to$6s6p $^3$P$_1$ intercombination line of mercury in the deep ultraviolet, by means of a frequency-comb referenced, wavelength-modulated, saturated absorption technique. This…

We have measured the Raman spectra of polycrystalline MgB$_{2}$ from 25 {\cm} to 1200 {\cm}. When the temperature was decreased below the superconducting transition temperature $T_c$, we observed a superconductivity-induced redistribution…

Superconductivity · Physics 2016-08-31 X. K. Chen , M. J. Konstantinovic , J. C. Irwin , D. D. Lawrie , J. P. Franck