Nm For Spectroscopy Research Articles

Spectral Shift and Split of Harmonic Lines in Propagation Affected High Harmonic Generation in a Long-Interaction Gas Tube

While generating high harmonics in long media of helium gas, at certain laser intensities and chirp, the spectral shift and split of the harmonic lines were experimentally observed, sometimes exceeding one harmonic order. Beyond reporting these results, numerical simulations were performed to understand the phenomenon. A 3D propagation model was solved under the strong field approximation. According to the simulations, the distortion of the laser beam profile during propagation and the consequently accused change in the conditions of phase matching are responsible for the observations. The observed phenomena can be an excellent tool to produce tunable narrow band harmonic sources covering a broad range around 13.5 nm for spectroscopy and for seeding X-ray lasers, and to understand non-desired detuning of the seed wavelength.

Demonstration of GaN‐based near UV Laser Diodes

Laser Technik JournalVolume 12, Issue 2 p. 16-16 CommunicationsFree Access Demonstration of GaN-based near UV Laser Diodes Realization of cw-operating LDs with emission wavelengths near 386 nm for spectroscopy, metrology, and lithography First published: 01 April 2015 https://doi.org/10.1002/latj.201590018AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume12, Issue2April 2015Pages 16-16 RelatedInformation

Atomic spectroscopy with squeezed light for sensitivity beyond the vacuum-state limit

A frequency tunable source of squeezed light has been developed which is suitable for a variety of spectroscopic applications. In initial experiments continuous tunability over a range of 2 GHz has been achieved with a directly observed nonclassical noise reduction of 6 dB relative to the vacuum-state limit in a balanced homodyne detector. A process of light-induced absorption in the nonlinear crystal has been identified as the principal loss mechanism which prevents the observation of yet larger degrees of squeezing. Although our source is potentially broadly tunable over the range of wavelengths from 840 to 970 nm, the current research centers on the performance at 852 nm for spectroscopy of the D 2 line of atomic cesium. For frequency-modulated (FM) saturation spectroscopy in a vapor cell, an improvement of 3.1 dB in sensitivity relative to the usual quantum limit is demonstrated for the detection of Doppler-free resonances. When corrected for the thermal noise of the detector, the enhancement in signal-to-noise ratio brought by the squeezed field is 3.8 dB relative to the shot-noise limit set by the vacuum fluctuations of the probe field.