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Showing papers on "Erbium published in 1986"


Journal ArticleDOI
TL;DR: In this paper, the authors investigated the photoluminescence of the rare earth element erbium implanted in GaAs, InP, and GaP through 10-K photoluminance essentially as a function of anneal temperature, time, and method.
Abstract: The characteristic 1.54‐μm emission from the rare‐earth element erbium implanted in GaAs, InP, and GaP was investigated through 10‐K photoluminescence essentially as a function of anneal temperature, time, and method. The strip‐heater, forming‐gas, and quartz‐ampoule anneal methods were utilized in the range of 400 to 1000 °C. Erbium‐related emissions were observed from 1.48 to 1.64 μm and were observable at emission temperatures of up to 260 K for InP:Er and 296 K for GaP:Er and GaAs:Er. Out of the three semiconductors, GaAs:Er was observed to exhibit the highest optical activation using a square‐profile implantation technique. Dependent on the anneal method, optimum Er emissions occurred between 650 and 800 °C for GaAs, for InP between 575 and 625 °C, and for GaP between 800 and 950 °C. In general, the forming‐gas anneal method proved most successful; however, maximum luminescence including sharper emission lines was achieved through the strip‐heater method. This method, with an anneal time of 10 s, sho...

118 citations


Patent
22 May 1986
TL;DR: In this paper, an improved transmission line is described in which the line is effectively formed as a continuous repeater amplifier by doping the fibre optic line with Neodymium or Erbium to an amount just sufficient to cancel out line losses for optical signals transmitted there along.
Abstract: Repeater amplifier in which a diode laser (20) or LED is coupled to a fibre link to activate the latter and provide positive gain, the link comprising a length (12) of the fibre optic transmission line doped with Neodymium or Erbium. An improved transmission line is described in which the line is effectively formed as a continuous repeater amplifier by doping the fibre optic line with Neodymium or Erbium to an amount just sufficient to cancel out line losses for optical signals transmitted therealong. Typical operaing wavelengths for the diode laser are 700 - 900nm. An advantage has been found by employing a carrier for the light signals of 1.318 microns for Neodymium doping and 1.54 microns for Erbium doping.

95 citations


Journal ArticleDOI
TL;DR: In this paper, a new type of current injection semiconductor laser with rare earth dopant in the active layer for achieving stable, single longitudinal mode operation was proposed, where the rare earth/semiconductor combination was chosen such that the wavelengths of the dominant emission from the trivalent rare earth ion internal 4f−4f transitions are shorter than that of the band-edge emission of the host semiconductor.
Abstract: We propose a new type of current injection semiconductor laser with rare‐earth dopant in the active layer for achieving stable, single longitudinal mode operation. In this laser, the rare‐earth/semiconductor combination is chosen such that the wavelengths of the dominant emission from the trivalent rare‐earth ion internal 4f‐4f transitions are shorter than that of the band‐edge emission of the host semiconductor. Spectrally, the narrow optical gain due to the rare‐earth ion transition will superimpose on top of the broad gain peak of the host semiconductor. Such laser diodes will attain lasing action at the rare‐earth transition wavelength resulting in single longitudinal mode operation with conventional Fabry–Perot cavity. Furthermore, reproducible precise lasing wavelength insensitive to temperature variation should be possible. Such a proposed rare‐earth/semiconductor injection laser was investigated with erbium doping in the GaInAsP (λ=1.55 μm) active layer of the heteroepitaxial ridge‐overgrown lase...

70 citations


Journal ArticleDOI
TL;DR: In this paper, the spectral, luminescence, and lasing properties of an yttrium scandium gallium garnet crystal activated with chromium and erbium were investigated.
Abstract: A study was made of the spectral, luminescence, and lasing properties of an yttrium scandium gallium garnet crystal activated with chromium and erbium. The lifetimes of the Stark sublevels of some of the levels of Er3+ were determined and the schemes of these sublevels were constructed. It was established that, in addition to the "forward" energy transfer, there was also the reverse process Er3+→Cr3+. The mechanism of the interaction and its microscopic constants were determined. The chromium and erbium concentrations could be varied within wide limits without significant deterioration in the conditions for the transfer of energy from Cr3+ to the 4I11/2 level of Er3+. A study was made of the lasing properties of this crystal (λl = 2.80 ± 0.01μ) under free-running and Q-switching conditions.

45 citations



Journal ArticleDOI
TL;DR: In this paper, a pulse-periodic picosecond erbium-doped garnet (Y3Al5O12:Er3+) laser with synchronous electrooptic modulation of losses in the resonator containing a partial polarizer was investigated.
Abstract: A pulse-periodic picosecond erbium-doped garnet (Y3Al5O12:Er3+) laser with synchronous electrooptic modulation of losses in the resonator containing a partial polarizer was investigated. The spectral and time characteristics of the fourth harmonic of the laser radiation (λ = 0.73μ) and also of the up-converted signal obtained by mixing with neodymium laser radiation (λ = 0.78μ) were determined as a function of the detuning between the modulation and intermode beat frequencies. Under optimal conditions the laser operated at a repetition frequency of 1–1.5Hz and it generated a train of 25 ultrashort pulses with an energy of 0.5MJ (± 3%) per spike and of 40 ± 10 psec duration at the fourth harmonic frequency. The relationship between the duration of the pulses τ and the width of the spectrum Δν of the fourth harmonic was τΔν~2. A parametric superradiance signal formed in a ZnGeP2 crystal pumped with the radiation from this erbiumlaser, operated in the ultrashort pulse regime, provided a reliable indication of the precision of optimization of the optical length of the resonator.

12 citations


Patent
22 May 1986
TL;DR: In this paper, an improved transmission line is described in which the line is effectively formed as a continuous repeater amplifier by doping the fibre optic line with Neodymium or Erbium to an amount just sufficient to cancel out line losses for optical signals transmitted there along.
Abstract: Repeater amplifier in which a diode laser (20) or LED is coupled to a fibre link to activate the latter and provide positive gain, the link comprising a length (12) of the fibre optic transmission line doped with Neodymium or Erbium. An improved transmission line is described in which the line is effectively formed as a continuous repeater amplifier by doping the fibre optic line with Neodymium or Erbium to an amount just sufficient to cancel out line losses for optical signals transmitted therealong. Typical operaing wavelengths for the diode laser are 700 - 900nm. An advantage has been found by employing a carrier for the light signals of 1.318 microns for Neodymium doping and 1.54 microns for Erbium doping.

11 citations



Journal ArticleDOI
TL;DR: In this article, a comparison between thermal and laser annealing of the implanted erbium ions was made and clear differences were found in the cathodoluminescence spectra of the thermally annealed and laser-annealed samples.

4 citations


Book ChapterDOI
04 Jun 1986
TL;DR: The energy transfer from chromium ions to yttrium-scandium-gallium garnet doped with chromium and erbium (YSGG:Cr3+, Er3+) was demonstrated in this article.
Abstract: The effective energy transfer from chromium ions not only to Nd3+, but also to Ho3+, Er3+, Tm3+, Yb3+ ions, is realized in gallium garnet crystals It enables one to propose a number of new active media schemes and to obtain efficient laser operation One of such media is yttrium-scandium-gallium garnet doped with chromium and erbium (YSGG:Cr3+, Er3+) Its composition was specially chosen with the aim of obtaining laser action on the erbium 4I11/2 → 4I13/2 transition in the spectral region around 3 μm/1,2/ The spectral and luminescence investigations have shown that the highest gain coefficient at room-temperature is reached at the wavelength λ = 2794 ± 0005 μm The lifetime of 4I11/2 state is 14 msec; and of the 4I13/2 state, 65 msec The energy transfer from chromium ions is the result of the static dipole-dipole interaction with its microparameter of 2 × 10−39cm6sec−1 and it finishes mainly on 4I9/2 and 4I11/2 levels of erbium ions It turns out, however, that backtransfer also takes place, that is the energy transfer from erbium to chromium ions starting from erbium 4S3/2 and 4F9/2 states The backtransfer is also static and dipole-dipole Its constants are 2 × 10−38cm6sec−1 and 10−38cm6sec−1 for 4F9/2 and 4S3/2, respectively The energy transfer from Er3+ to Cr3+ ions is also possible from the higher erbium states We must emphasize that the Er3+ → Cr3+ energy transfer does not lead to any noticeable diminishing of the Er3+ ions 4I11/2 upper laser level population, because of the energy received by chromium from erbium practically all (with the proper erbium concentrations) is returned to Er3+ ions The presence of the direct and the back energy transfer between Cr3+ and Er3+ ions makes the picture of population and depletion of different erbium levels exceedingly complex

3 citations




Book ChapterDOI
01 Jan 1986
TL;DR: In this article, the process of the growth of erbium crystals by evaporation from vapour onto a surface of tungsten under UHV conditions was investigated by using the technique of field electron emission microscopy.
Abstract: The process of the growth of erbium crystals by evaporation from vapour onto a surface of tungsten under UHV conditions was investigated. The experiment was carried out by using the technique of field electron emission microscopy [1,2]. A feature of this technique is a hemispherical form of the 0 substrate with a tip curvature radius of order of thousand A. The substrate is usually a single crystal, the spherical surface of which exposes several low index crystaliographic planes. The atom flux impinging onto such a surface is accommodated on it and the condensation process mostly occurs in a different way on different regions of the substrate surface due to a significant anisotropy of the electronic structure of the surface. The aim of this work was to examinewhich crystallographic type of the surface of tungsten is preferential for the growth of erbium crystals and to find favourable conditions for growing big crystals of erbium the size of which would be comparable with the size of the substrate.

Journal ArticleDOI
TL;DR: In this article, the normal and second derivative UV-VIS and normal near-IR spectra of tripositive erbium ion in acetate, nitrate and sulphate solutions were investigated and the interaction (E0, E1, E2, E3, ξ4f, α, β, γ, T2, T3, T4, T6, T7, T8) and intensity ( Ω 2, Ω 4, Ω 6 ) parameters were derived.
Abstract: Normal and second derivative UV-VIS and normal near-IR spectra of tripositive erbium ion in acetate, nitrate and sulphate solutions of erbium, ammonium, magnesium, potassium and sodium have been investigated. Interaction (E0, E1, E2, E3, ξ4f, α, β, γ, T2, T3, T4, T6, T7, T8) and intensity ( Ω 2 , Ω 4 , Ω 6 ) parameters are derived. Radiative lifetimes of the fluorescent levels are estimated from the measured absorption intensities. Variations in intensities of the hypersensitive transition bands are discussed.