Search results for "Tunable laser"
showing 10 items of 41 documents
Resonant Ionization Laser Ion Source for Radioactive Ion Beams
2009
A resonant ionization laser ion source based on all‐solid‐state, tunable Ti:Sapphire lasers is being developed for the production of pure radioactive ion beams. It consists of a hot‐cavity ion source and three pulsed Ti:Sapphire lasers operating at a 10 kHz pulse repetition rate. Spectroscopic studies are being conducted to develop ionization schemes that lead to ionizing an excited atom through an auto‐ionization or a Rydberg state for numerous elements of interest. Three‐photon resonant ionization of 12 elements has been recently demonstrated. The overall efficiency of the laser ion source measured for some of these elements ranges from 1 to 40%. The results indicate that Ti:Sapphire lase…
Simple digital system for tuning and long-term frequency stabilization of a CW Ti:Sapphire laser
2015
We have implemented a simple digital system for long-term frequency stabilization and locking to an arbitrary wavelength of the single-frequency ring CW Ti:Sapphire laser. This system is built using two confocal Fabry-Perot cavities, one of which is used to narrow the short-term linewidth of the laser and the other to improve the long-term stability of the laser frequency. The length of the second cavity is stabilized using the radiation from an external-cavity diode laser locked to an atomic transition. Our system is an improvement of a commercial Tekhnoscan laser lock. This system has been successfully used in our experiments on high-resolution laser spectroscopy of ultracold rubidium Ryd…
Tunable narrowband fiber laser with feedback based on whispering gallery mode resonances of a cylindrical microresonator.
2013
Narrowband filtering based on whispering gallery modes of a slightly tapered cylindrical optical microresonator was used to implement a tunable narrowband erbium-doped fiber laser. The laser can be set to emit a single longitudinal cavity mode (single frequency), although the laser cavity is a few meters long. In the single-frequency regime the laser can emit a maximum power of 0.380 mW with a linewidth <35 kHz and a signal-to-noise ratio exceeding 50 dB. Tunability is achieved by sliding the excitation point along the microcylinder. A tuning range of 1.16 nm is demonstrated.
Active Q-switched distributed feedback erbium-doped fiber lasers
2005
This letter presents a distributed feedback fiber laser that operates in an actively controlled Q-switched regime. The laser is based on a Bragg grating made in an erbium-doped fiber. The grating has a defect induced by a magnetostrictive transducer that configures the distributed feedback laser structure. The phase shift generated by the defect can be dynamically modified by an electric current, permitting active Q-switching of the laser. The laser generates pulses of 75 ns duration and the repetition rate can be continuously adjusted from 0 to 10 kHz.
Dissipative Solitons, a Novel Paradigm for Mode-locked Lasers
2013
The concept of a "dissipative soliton" provides an excellent framework for understanding complex mode-locked laser pulse dynamics from a unified picture. It has stimulated innovative laser cavity designs in the past few years. This tutorial lecture provides conceptual pictures illustrated with universal dynamics, highlights recent achievements and prospects for mode-locked laser development.
Application of sol-gel and laser evaporation methods to obtain thin gas sensitive films
2005
New type resistive/capacitative gas sensitive structures were obtained by using a specially prepared substrate- glass, covered by thin conducting In/sub 2/O/sub 3/ layer, cutted into a comb teeth-type electrodes by help of laser beam. Such laser processed gap in the layer of conducting material was a prototype of excellent humidity sensor, especially at high values of relative humidity (RH). Different additional coatings onto a laser processed gap were examined for humidity sensing. Sol-gel, vacuum thermal evaporation and laser evaporation methods were used to obtain a thin layers of different materials.
Triple resonant four-wave mixing: A microwatt continuous-wave laser source in the vacuum ultraviolet region at 120 nm
2012
We present a vacuum ultraviolet laser source by four-wave mixing in mercury vapour based on solid-state laser systems. Maximum powers of 6μW were achieved with an increase of four orders of magnitude in efficiency.
Observability of the Risken–Nummedal–Graham–Haken instability in Nd:YAG lasers
2003
Multilongitudinal mode instability in ring Nd:YAG lasers is theoretically analyzed. After we review the way in which the standard two-level laser theory applies to this laser we extend the theoretical treatment to include transverse effects. We do this by taking into account the finite transverse section of the active medium and by assuming a Gaussian transverse distribution for the intracavity field. Finally we demonstrate that multimode emission develops whenever the intracavity field waist diameter is almost equal to the active rod diameter. We conclude that continuous-wave diode-pumped Nd:YAG lasers with low cavity losses are good candidates for the observation of the Risken–Nummedal–Gr…
Tunable Dual-Wavelength Thulium-Doped Fiber Laser Based on FBGs and a Hi-Bi FOLM
2017
A tunable dual-wavelength thulium doped fiber laser is demonstrated experimentally. For the first time for the 2- $\mu \text{m}$ wavelength band we propose the independent tuning of the generated laser lines based on fiber Bragg gratings and the use of a Hi-Bi fiber optic loop mirror for the fine adjustment of the cavity losses to obtain stable dual-wavelength operation. Dual-wavelength laser generation with the laser lines separation in the range from 0.3 to 6.5 nm is obtained. The laser emission exhibits an optical signal-to-noise ratio better than 56 dB. Improved stability with output power fluctuations less than 1 dB is observed in dual-wavelength generation with equal power of lines.
"Smart" defects in colloidal photonic crystals
2005
AbstractWe present a bottom-up approach for the construction of "Smart" active defects in colloidal photonic crystals (CPCs). These structures incorporate polyelectrolyte multilayer (PEM) planar defects embedded in silica CPCs through a combination of evaporation induced self-assembly and microcontact transfer printing. We show how the enormous chemical diversity inherent to PEMs can be harnessed to create chemically active defect structures responsive to solvent vapor pressures, light, temperature as well as redox cycling. A sharp transmission state within the photonic stopband, induced by the PEM defect, can be precisely, reproducibly and in some cases reversibly tuned by these external s…