Analysis of Tungstates and Sesquioxides, Two of the Best Yb3+-Doped Laser Crystals According to Different Evaluations.

ABSTRACTThe development of reliable InGaAs laser diode pump sources emitting in the 900-980 nm spectral range is stongly influencing the field of lasers based on Yb3+-doped solid state crystals. Ca5(PO4)3F (C-FAP) and S-FAP (Sr5(PO4)3F) were soon recognized to be favourable hosts for Yb3+ lasing in the nanosecond pulse regime. This fact was supported by an evaluation of the spectroscopic properties of several Yb3+-doped crystals useful for laser action. This evaluation is based on two parameters known from spectroscopy, the emission cross-section at the laser wavelength and the minimum pump intensity required to achieve transparency at the laser wavelength.We think there is a need of a new evaluation of Yb3+-doped crystals in order to predict the laser efficiency in a more realistic manner in different kinds of regimes. We present here the main spectroscopic properties of two Yb3+-doped laser crystals which are grown in our Group: (i) KY(WO4)2 double tungstates by the Floating Crystal method and (ii) Y2O3sesquioxides by the Laser Heated Pedestal Growth method. The approach, based on a quasi-three level laser model, leads to compare all known Yb3+-doped crystals in a two-dimensional diagram considering the laser extracted power and the slope efficiency. We shall show that tungstates and sesquioxides belong to the highest laser crystal potential in CW-end pumping configuration.

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Investigation on the Spectroscopic Properties of Yb3+-doped Phosphate Glass

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.335-336.1035 ◽

2011 ◽

Vol 335-336 ◽

pp. 1035-1038

Author(s):

Qi Sang ◽

Shao Jun Wang ◽

Xue Rong Wang ◽

Jing Wen Lu

Keyword(s):

Cross Section ◽

Spectral Properties ◽

Emission Cross Section ◽

Emission Spectra ◽

Spectroscopic Properties ◽

Pump Intensity ◽

Doping Content ◽

Performance Parameters ◽

Particle Count ◽

Laser Glass

A series of the Yb3+ -doped phosphate laser glass have been prepared under high temperature and different doping content and the fluorescence and absorption spectrum is observed, respectively. The influences of the Yb3+ -doped content on the spectral properties of the glass are analyzed and the optimal mole fraction is 4 %. The emission cross-section and fluorescent lifetime is calculated with McCumber theory. Furthermore, the integrated absorption cross-section, the full width at half maximum of the emission spectra and the laser performance parameters such as least particle count, saturation pump intensity and lowest pump intensity of Yb3+ -doped laser glass is calculated.

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VUV SPECTROSCOPY OF CRYSTALLINE EMITTERS BASED ON 5d–4f TRANSITIONS IN RARE EARTH IONS

Surface Review and Letters ◽

10.1142/s0218625x02002919 ◽

2002 ◽

Vol 09 (01) ◽

pp. 621-626 ◽

Cited By ~ 4

Author(s):

V. N. MAKHOV ◽

N. YU. KIRIKOVA ◽

N. M. KHAIDUKOV ◽

M. KIRM ◽

E. NEGODIN ◽

...

Keyword(s):

Stokes Shift ◽

Laser Action ◽

Spectroscopic Properties ◽

Rare Earth Ions ◽

Stimulated Emission ◽

Solid State Lasers ◽

Nonradiative Relaxation ◽

Level Laser ◽

Vuv Spectroscopy ◽

Strong Spin

The spectroscopic properties of several fluoride crystals ( LiYF 4, KYF 4, K 2 YF 5, KLiYF 5, CsY 2 F 7, SrF 2) doped with Nd 3+, Er 3+ or Tm 3+ are analyzed from the viewpoint of their possible applications as active media for VUV solid state lasers. It has been found that in many crystals there exists very efficient nonradiative relaxation from higher-lying 5d states to the lowest 5d level responsible for the spin-forbidden luminescence. In fact, the energy level diagram of 5d–4f transitions for these two ions represents a typical four-level laser scheme with a considerably larger Stokes shift of 5d–4f luminescence from the edge of the strong spin-allowed 4f–5d absorption than for Nd 3+, which causes smaller reabsorption of emitted VUV radiation in the crystals doped with Er 3+ or Tm 3+. Two crystals LiYF 4: Nd 3+ and SrF 2: Er 3+ were tested for laser action under pumping by a pulsed F 2 laser operating at 157 nm. However, no indications of the appearance of stimulated emission have been detected for both crystals. The possible reasons for the absence of lasing are discussed.

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Physical and Spectroscopic Properties of Yb3+-Doped Fluorophosphate Laser Glasses

Laser Chemistry ◽

10.1155/2008/656490 ◽

2008 ◽

Vol 2008 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Shujiang Liu ◽

Anxian Lu

Keyword(s):

Power Generation ◽

Refractive Index ◽

Cross Section ◽

Emission Cross Section ◽

Spectroscopic Properties ◽

Pump Intensity ◽

Gain Coefficient ◽

Mechanical And Thermal Properties ◽

Fluorophosphate Glass ◽

Excellent Candidate

The physical properties including refractive index, Abbe number, nonlinear refractive index, microhardness and thermal expansion coefficient, and spectroscopic properties of Yb3+-doped fluorophosphate laser glasses were investigated. The results show that due to the addition of fluoride, mechanical and thermal properties are promoted, emission cross-section σemi is also greatly enhanced. The largest gain coefficient σemi·τm (0.824 pm2·ms) can be obtained with the minimum pump intensity Imin (1.112 kw/cm2). This kind of Yb3+-doped fluorophosphate glass is an excellent candidate material for Yb3+-doped host for high-power generation.

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Temperature-Dependent Stimulated Emission Cross-Section in Nd3+:YLF Crystal

Materials ◽

10.3390/ma14020431 ◽

2021 ◽

Vol 14 (2) ◽

pp. 431

Author(s):

Giorgio Turri ◽

Scott Webster ◽

Michael Bass ◽

Alessandra Toncelli

Keyword(s):

Cross Section ◽

Cross Sections ◽

Room Temperature ◽

Radiative Decay ◽

Emission Cross Section ◽

Spectroscopic Properties ◽

Stimulated Emission ◽

Different Temperatures ◽

Stimulated Emission Cross Section ◽

Semi Empirical

Spectroscopic properties of neodymium-doped yttrium lithium fluoride were measured at different temperatures from 35 K to 350 K in specimens with 1 at% Nd3+ concentration. The absorption spectrum was measured at room temperature from 400 to 900 nm. The decay dynamics of the 4F3/2 multiplet was investigated by measuring the fluorescence lifetime as a function of the sample temperature, and the radiative decay time was derived by extrapolation to 0 K. The stimulated-emission cross-sections of the transitions from the 4F3/2 to the 4I9/2, 4I11/2, and 4I13/2 levels were obtained from the fluorescence spectrum measured at different temperatures, using the Aull–Jenssen technique. The results show consistency with most results previously published at room temperature, extending them over a broader range of temperatures. A semi-empirical formula for the magnitude of the stimulated-emission cross-section as a function of temperature in the 250 K to 350 K temperature range, is presented for the most intense transitions to the 4I11/2 and 4I13/2 levels.

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Development of temporal spectroscopic properties for Xerogel matrices doped with Rhodamine 6G dye

Open Physics ◽

10.2478/s11534-006-0017-y ◽

2006 ◽

Vol 4 (3) ◽

Author(s):

Abbas Al-Wattar ◽

Baha Chiad ◽

Wesam Twej ◽

Sarmed Al-Awadi

Keyword(s):

Fluorescence Spectra ◽

Rhodamine 6G ◽

Sol Gel ◽

Blue Shift ◽

Spectroscopic Properties ◽

Dye Molecules ◽

Absorption And Fluorescence Spectra ◽

Silica Network ◽

Sol Gel Process ◽

Two Parameters

AbstractThe solid host of a laser dye modifies its spectroscopic properties with respect to its liquid host. During the Sol-Gel process the dye molecules suffer from changing their environment. Two parameters affect this matter, the change in the concentration due to the evaporation of the solvent (drying) and the caging of dye molecules inside the pores or attachment to the silica network. Rhodamine 6G absorption and fluorescence spectra with different concentrations, during Sol-Gel time processing, have been studied. Both, absorption and fluorescence spectra of the dye in the solid host, for different concentrations, show a blue-shift relative to its liquid phase.

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