Online ISSN
1350-911X
Print ISSN
0013-5194
Electronics Letters
Volume 23, Issue 1, 2 January 1987
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Volume 23, Issue 1
2 January 1987
Model for the switching voltage of miss devices based on an analogy with the thyristor
- Author(s): W.K. Choi ; A.E. Owen ; J.J. Delima ; S.M. Gage
- Source: Electronics Letters, Volume 23, Issue 1, p. 1 –2
- DOI: 10.1049/el:19870001
- Type: Article
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A model for the switching voltage of MISS devices based on an analogy with the thyristor is presented. The weak dependence of the switching voltage on the doping of the intermediate semiconductor layer in the range of medium and heavy doping levels (≥1015cm−3) can be quantitatively accounted for, and comparisons are made with published data from several sources.
Waveguide-integrated pin photodiode on InP
- Author(s): C. Bornholdt ; W. Döldissen ; F. Fiedler ; R. Kaiser ; W. Kowalsky
- Source: Electronics Letters, Volume 23, Issue 1, p. 2 –4
- DOI: 10.1049/el:19870002
- Type: Article
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An InGaAs PIN photodiode was vertically integrated with an inverted optical rib waveguide in InGaAsP. Guided light was transferred to and absorbed by the photodiode at a rate of 0.07dB/μm. For detectors with sufficient length (>300μm) a responsivity of 0.81 A/W was achieved at 1.3 μm wave-length.
Extended power method and stability of linear discrete-time systems
- Author(s): S. Puthenpura and N.K. Sinha
- Source: Electronics Letters, Volume 23, Issue 1, p. 4 –5
- DOI: 10.1049/el:19870003
- Type: Article
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A computationally simple and efficient method is proposed to determine the stability of linear discrete-time systems. The method directly utilises the system (state-transition) matrix and avoids the evaluation of the characteristic polynomial. Another interesting feature of this approach is that it can be extended to extract the eigenvalues of matrices, in a recursive fashion.
Generation of a single-lobe radiation pattern from a phased-array laser using a near-contact variable phase-shift zone plate
- Author(s): S. Thaniyavarn and W. Dougherty
- Source: Electronics Letters, Volume 23, Issue 1, p. 5 –7
- DOI: 10.1049/el:19870004
- Type: Article
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A very simple and practical technique to generate a stable, narrow-angle single-lobe far-field radiation pattern from an ordinary twin-lobe phase-locked laser diode array is demonstrated. A variable phase-shift zone plate mounted close to the laser output facet is used to readjust the phase distribution of the array into an all-in-phase distribution producing the desired single narrow-lobe far-field pattern.
Growth temperature dependence of low-noise MESFET in molecular-beam epitaxy
- Author(s): Y.C. Chou ; C.T. Lee ; C.D. Chen ; K.C. Chu
- Source: Electronics Letters, Volume 23, Issue 1, p. 7 –8
- DOI: 10.1049/el:19870005
- Type: Article
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The substrate growth temperature dependence of electrical properties for a low-noise MESFET fabricated on MBE-grown material has been demonstrated. The optimum noise figure and its associated gain were attributed to the higher epilayer quality and mobility at a growth temperature of 650°C between temperatures of 550°C and 700°C.
Characterisation of n-channel germanium MOSFET with gate insulator formed by high-pressure thermal oxidation
- Author(s): E.E. Crisman ; J.I. Lee ; P.J. Stiles ; O.J. Gregory
- Source: Electronics Letters, Volume 23, Issue 1, p. 8 –10
- DOI: 10.1049/el:19870006
- Type: Article
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N-channel Ge MOSFETs are fabricated with the use of a double-layer gate oxide consisting of electron beam evaporated SiO2 over a native GeO2 oxide, formed by highpressure thermal oxidation. Interface properties of the MOS structure, determined by capacitance/voltage and mobility measurements, are shown to be suitable for FET devices.
Influence of impurities on loss increase in optical fibre
- Author(s): H. Hanafusa ; Y. Hibino ; H. Itoh ; F. Yamamoto
- Source: Electronics Letters, Volume 23, Issue 1, p. 10 –11
- DOI: 10.1049/el:19870007
- Type: Article
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The influence of impurities on hydrogen-induced OH loss increase and radiation-induced loss increase is examined in GeO2-doped SiO2 fibres with a synthetic SiO2 clad. Fibres contaminated by both aluminium and sodium ions show loss increases as great as fibres with a natural SiO2 clad.
Very high-transconductance short-channel GaAs MESFETs with Ga0.3Al0.7As buffer layer
- Author(s): K.Y. Lee ; M. Al-Mudares ; S.P. Beaumont ; C.D.W. Wilkinson ; J. Frost ; C.R. Stanley
- Source: Electronics Letters, Volume 23, Issue 1, p. 11 –12
- DOI: 10.1049/el:19870008
- Type: Article
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MESFETs with 0.17μm gate length were manufactured with an n+GaAs active layer (3 × 1018cm-3) and an undoped Ga0.3Al0.7As buffer layer grown by molecular-beam epitaxy. The deives showed very high transconductance (700mS/mm) with good pinchoff characteristics. The experimental transconductance values were compared with calculated ones using a model that assumed total carrier confinement within the active layer by a barrier potential at the GaAs/GaAlAs interface. The results suggest that very high-transconductance short-gate-length MESFETs can be fabricated with a heavily doped GaAs active layer provided that the carrier density in the active layer is maintained at the doping level.
Frequency modulation and spectral characteristics for a 1.5μm phase-tunable DFB laser
- Author(s): S. Murata ; I. Mito ; K. Kobayashi
- Source: Electronics Letters, Volume 23, Issue 1, p. 12 –14
- DOI: 10.1049/el:19870009
- Type: Article
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Frequency modulation (FM) and spectral characteristics for a 1.5μm phase-tunable DFB (PT DFB) laser have been studied experimentally. As tuning current was increased, light output, lasting wavelength, FM efficiency and spectral linewidth changed periodically. The continuous-wavelength tuning range was over l.2nm (150 GHz). A high FM efficiency, more than 16GHz/mA, and a flat FM response, up to 100MHz, were obtained.
Single-mode single-polarisation fibre using resonant absorbing effect
- Author(s): Zheng Xue-Heng
- Source: Electronics Letters, Volume 23, Issue 1, p. 14 –15
- DOI: 10.1049/el:19870010
- Type: Article
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Modes of two parallel fibres exhange energy completely only when their propagation constants are identical. When one fibre is birefringent, and the other isotropic and lossy, the energy of one polarisation mode swaps back and forth between two fibres and is eventually absorbed.
Resolution of moment equations in a nonlinear optical amplifier
- Author(s): S. Ruiz-Moreno ; G. Junyent ; J.R. Usandizaga ; A. Calzada
- Source: Electronics Letters, Volume 23, Issue 1, p. 15 –17
- DOI: 10.1049/el:19870011
- Type: Article
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In the letter a new method for the resolution of the moment equations in a nonlinear optical amplifier is exposed. Results for the four first moments for the saturated and unsaturated absorption cases are presented. These results are in good agreement with those obtained by other authors.
Molybdenum germanide ohmic contact to n-GaAs
- Author(s): K. Daoud-Ketata ; C. Dubon-Chevallier ; C. Besombes ; J.F. Bresse ; P. Henoc
- Source: Electronics Letters, Volume 23, Issue 1, p. 17 –18
- DOI: 10.1049/el:19870012
- Type: Article
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GeMo refractory ohmic contacts for n-type GaAs with a specific contact resistivity as low as 10-6Ωcm2 have been obtained on 1018cm-3 epitaxial layers. This low resistivity was obtained by contact annealing under As overpressure. Contacts using As-doped Ge layers and annealed without As overpressure have also been realised; in this case the obtained resistivity was 5 × 10-6Ωcm2. The ohmic contact formation resulted from the creation of an n+ layer by Ge overdoping and the formation of a molybedenum germanide stable phase.
Nonlinear feedback control of a class of nonlinear systems
- Author(s): A. Yethiraj and C.B. Smith
- Source: Electronics Letters, Volume 23, Issue 1, p. 18 –20
- DOI: 10.1049/el:19870013
- Type: Article
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A nonlinear feedback controller is designed on the basis of a truncated Volterra series representation of the process model, the necessary parameters of which can be obtained via suitable experiments. A simple example demonstrates the increased range and improved performance of the nonlinear controller compared to two linear controllers.
Quasisinusoidal oscillators with cubic-type nonlinearity
- Author(s): C. Di Bello
- Source: Electronics Letters, Volume 23, Issue 1, p. 20 –21
- DOI: 10.1049/el:19870014
- Type: Article
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It is shown how nonlinearities of cubic type, regardless of their degree of nonlinearity, are appropriate in the synthesis of quasinusoidal oscillators of any order. The existence of a suitable ‘small parameter’ ɛ in the linear circuit of the oscillator and the design of its parameters by simple conditions ensure quasinusoidal oscillation. Application examples involving some typical circuits are then given.
Current-mirror phase-shifter oscillator
- Author(s): S. Pookaiyaudom and K. Samootrut
- Source: Electronics Letters, Volume 23, Issue 1, p. 21 –23
- DOI: 10.1049/el:19870015
- Type: Article
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Recently proposed differential current mirrors have been used to realise phase-shifter circuits. Two of these phase-shifters are then cascaded to form a high-performance sinusoidal oscillator, where all active functional blocks are current mirrors.
Wideband variable peaking AGC amplifier for high-speed lightwave digital transmission
- Author(s): T. Kinoshita ; K. Yamashita ; M. Maeda ; Y. Sekine
- Source: Electronics Letters, Volume 23, Issue 1, p. 23 –24
- DOI: 10.1049/el:19870016
- Type: Article
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A variable peaking AGC amplifier with a new circuit configuration is proposed and monolithically integrated by using 1 μm Si-bipolar technology. The amplifier exhibits characteristics of l.8 GHz bandwidth, 9 dB maximum gain and 15 dB gain dynamic range, and is 1.8 times superior to nonpeaking amplifiers.
Dispersion of pure GeO2 glass core and f-doped GeO2 glass cladding single-mode optical fibre
- Author(s): T. Hosaka ; S. Sudo ; K. Okamoto
- Source: Electronics Letters, Volume 23, Issue 1, p. 24 –26
- DOI: 10.1049/el:19870017
- Type: Article
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The letter investigates the dispersion of GeO2 glass core and F-doped GeO2 glass cladding single-mode optical fibre. It is estimated that the total dispersion goes to zero at about λ = 1.77 μm. The material dispersions of these glasses are also measured. Material dispersion of GeO2 glass, which contains fluorine of 0.41 wt%, vanished at λ = 1.722μm. This occurs at λ = 1.734 μm for pure GeO2 glass.
Comment: Temperature distribution on ceramic substrates
- Author(s): D.J. Dean
- Source: Electronics Letters, Volume 23, Issue 1, page: 26 –26
- DOI: 10.1049/el:19870018
- Type: Article
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Reply: Temperature distribution on ceramic substrates
- Author(s): E. Boone ; G. de Mey ; L. Rottiers
- Source: Electronics Letters, Volume 23, Issue 1, page: 26 –26
- DOI: 10.1049/el:19870019
- Type: Article
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Mutual coupling between circular disc microstrip antennas
- Author(s): K. Mahdjoubi ; E. Penard ; J.P. Daniel ; C. Terret
- Source: Electronics Letters, Volume 23, Issue 1, p. 27 –28
- DOI: 10.1049/el:19870020
- Type: Article
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The mutual coupling between microstrip antennas is studied by applying the reaction theorem and the cavity model. A semianalytic formula is derived for disc antennas which takes into account the dependence on the relative angular position of the antennas, as well as on the angular feeding point poisition. Theoretical results are in good agreement with measurements.
Resonant tunnelling electron spectroscopy
- Author(s): F. Capasso ; S. Sen ; A.Y. Cho ; A.L. Hutchinson
- Source: Electronics Letters, Volume 23, Issue 1, p. 28 –29
- DOI: 10.1049/el:19870021
- Type: Article
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The energy distribution of hot electrons quasiballistically injected in p+ GaAs has been probed directly using the tunnelling resonances of a double barrier in a specially designed two-terminal heterojunction device. The photocurrent/voltage characteristics give direct information on the hot electron spectrum, without requiring derivative techniques.
Low-loss TM-pass polariser fabricated by proton exchange for z-cut ti:LiNbO3 waveguides
- Author(s): J.J. Veselka and G.A. Bogert
- Source: Electronics Letters, Volume 23, Issue 1, p. 29 –31
- DOI: 10.1049/el:19870022
- Type: Article
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We fabricated a low-loss TM-pass polariser at λ = 1.32 μm integrated with low-loss titanium waveguides in Z-cut LiNbO3. The polariser, fabricated by proton exchange, had an excess insertion loss of 0.3 dB and a polarisation extinction ratio of > 40dB.
General probability density function of packet service times for computer networks
- Author(s): M. Ilyas
- Source: Electronics Letters, Volume 23, Issue 1, p. 31 –32
- DOI: 10.1049/el:19870023
- Type: Article
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The letter presents derivations of a generalised probability density and distribution functions of packet service times for computer communication networks. Included in the derivation are the effects of message segmentation into packets and the effects of control traffic. We also present the first and the second moments of the packet service times. These expressions can be used in modelling and analysis of computer networks by assigning appropriate values to various parameters.
Efficient frequency up-conversion via energy transfer in fluoride glasses
- Author(s): R.S. Quimby ; M.G. Drexhage ; M.J. Suscavage
- Source: Electronics Letters, Volume 23, Issue 1, p. 32 –34
- DOI: 10.1049/el:19870024
- Type: Article
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The conversion of infra-red to visible light has been studied in a series of fluoride glasses doped with YbF3 and ErF3. The frequency up-conversion efficiency of these bulk materials is four orders of magnitude greater than that observed in doped oxide glasses, and compares very favourably with results obtained for Yb3+/Er3+-containing crystals.
Entirely VPE-grown 1-5μm DFB lasers with low threshold currents
- Author(s): T. Nishibe ; M. Funamizu ; H. Okuda ; H. Furuyama ; Y. Hirayama ; M. Nakamura ; M. Iwamoto
- Source: Electronics Letters, Volume 23, Issue 1, p. 34 –35
- DOI: 10.1049/el:19870025
- Type: Article
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Entirely hydride VPE-grown 1.5μm DFB lasers have been obtained by means of high controllability in film thickness and alloy composition for the GalnAsP/InP system. A low threshold current of 13 mA was achieved by improving the growth method for the layer burying the grating. High uniformity in threshold current and lasing wavelength (Ith = 27.3 ± 9.7 mA, λ = 15571 ± 12Å) was obtained.
Slope angle influence on silicon doping in AlGaAs/GaAs MBE-grown on stepped surface of (100) GaAs substrate
- Author(s): H. Nobuhara ; O. Wada ; T. Fujii
- Source: Electronics Letters, Volume 23, Issue 1, p. 35 –36
- DOI: 10.1049/el:19870026
- Type: Article
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Formation of a series of lateral p-n junctions has been observed in molecular-beam-epitaxial Si-doped AlGaAs/GaAs grown on a graded-step surface of a (100) GaAs substrate. The lateral p-n junction has been found to be formed in a region where a slope angle θ of the graded-step surface changes gradually; the conductivity is n-type for 0° < θ < 21° but it converts to p-type for θ > 31°. A critical angle in the conductivity reversal has been first observed on a single substrate.
Ti:LiNbO3 three-waveguide polarisation splitter
- Author(s): G.A. Bogert
- Source: Electronics Letters, Volume 23, Issue 1, p. 37 –38
- DOI: 10.1049/el:19870027
- Type: Article
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A Ti: LiNbO3 waveguide device that combines the beam-splitter and polariser functions into a single component is presented. This three-waveguide device is designed to split the TM mode equally to the two outer output ports while guiding the TE mode out of the centre guide. The device is low-loss, provides equal splitting and passively delivers–20 dB of polarisation extinction. Electro-optical tuning would improve this value.
InGaAs PIN photodiodes grown on GaAs substrates by metal organic vapour phase epitaxy
- Author(s): A.G. Dental ; J.C. Campbell ; C.H. Joyner ; G.J. Qua
- Source: Electronics Letters, Volume 23, Issue 1, p. 38 –39
- DOI: 10.1049/el:19870028
- Type: Article
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We have fabricated and characterised high-efficiency, long-wavelength PIN photodiodes on In0.53Ga0.47As/InP/GaAs wafers grown by metal organic vapour phase epitaxy. Initial measurements indicate that good quality devices can be made in this highly stressed material system (lattice mismatch ~3.8%). These results suggest the possibility of fabricating optoelectronic integrated circuits (OEICs) by combining InGaAs(P) electro-optic devices with high-speed GaAs electronics.
Soi by wafer bonding with spin-on glass as adhesive
- Author(s): A. Yamada ; T. Kawasaki ; M. Kawashima
- Source: Electronics Letters, Volume 23, Issue 1, p. 39 –40
- DOI: 10.1049/el:19870029
- Type: Article
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Two silicon wafers were bonded together with spin-on glass as the adhesive. Bonding strength depended heavily on the surface treatment. This was also confirmed by IR reflection measurement. A silicon-on-insulator (SOI) structure was achieved by thinning one of the wafers after the bonding. The resultant 5μm-thick SOI layer was stable at high temperatures and showed no degradation in its electrical characteristics.
Numerical convergence in calculating the propagation constants by the transverse modal analysis technique
- Author(s): T.N. Chang
- Source: Electronics Letters, Volume 23, Issue 1, p. 40 –42
- DOI: 10.1049/el:19870030
- Type: Article
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Numerical accuracy in calculating the dispersive nature by the transverse modal analysis is rechecked. It has been found that numerical accuracy can be further improved by taking account of the symmetrical property of the dominant mode.
Multiple-wave generation due to four-wave mixing in a single-mode fibre
- Author(s): H.H. Yaffe ; R.G. Waarts ; E. Lichtman ; A.A. Friesem
- Source: Electronics Letters, Volume 23, Issue 1, p. 42 –44
- DOI: 10.1049/el:19870031
- Type: Article
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By suppressing stimulated Brillouin scattering, strong four-wave mixing of two waves was obtained in a 400 m single-mode fibre. As the input was raised, newly generated waves were observed, in accordance with an exact analytical solution. With a maximum power of 230 mW for each input wave, 65% of the power was transferred into six newly generated waves.
Observations on 2 and 7.5 GHz microwave links during dust storms
- Author(s): S.I. Ghobrial ; M.A. Hemeidi ; M.E. Tawfig
- Source: Electronics Letters, Volume 23, Issue 1, p. 44 –45
- DOI: 10.1049/el:19870032
- Type: Article
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Observations on 2 GHz and 7.5 GHz microwave links operating in Khartoum revealed that the attenuation effect of dust storms is negligible. Attenuations of less than 0.5 dB were recorded during storms with visibilities of less than 200 m. This confirms theoretical findings made by a number of workers.
Novel sorter architecture for image processing rank order filters
- Author(s): U. Kleine
- Source: Electronics Letters, Volume 23, Issue 1, p. 45 –46
- DOI: 10.1049/el:19870033
- Type: Article
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In this letter a novel sorter architecture for two-dimensional rank order filters is presented. Rank order filters are widely used in image processing applications to smooth noisy images without perturbing edge structures. The main element of such filters is a sorter. In the letter a parallel sorting network is described, based on Batcher's odd-even merge algorithm. The required chip area of the sorter network is proportional to N(log2N)[(log2N) + 1], where N is the number of pixels to be sorted. An example of a 25-pixel sorter network is given.
Sensitivity of driving-point function based wave digital filters
- Author(s): K.S. Prasad and C. Eswaran
- Source: Electronics Letters, Volume 23, Issue 1, p. 46 –47
- DOI: 10.1049/el:19870034
- Type: Article
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It is shown that the passband sensitivity advantage with respect to the terminating multipliers claimed for driving-point based wave digital filters does not exist in practice. It is also shown that the performance of these filters is poor compared to that of conventional transfer function based wave digital filters as far as the stopband sensitivity is concerned.
Very broadband flat coupling hybrid ring
- Author(s): A.S. Wright and S.K. Judah
- Source: Electronics Letters, Volume 23, Issue 1, p. 47 –49
- DOI: 10.1049/el:19870035
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The bandwidth of a microwave microstrip hybrid ring has been extended to 28%. Double quarter-wave transformers are used, maintaining very flat coupling.
Coherent optical fibre system with Zeeman lasers
- Author(s): Wu Yizun ; Tian Feng ; Yang Xinwei ; Yu Tong
- Source: Electronics Letters, Volume 23, Issue 1, p. 49 –50
- DOI: 10.1049/el:19870036
- Type: Article
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A coherent optical fibre system is studied in which two Zeeman lasers are used as local oscillator and transmitter laser, and which work independently of each other without any frequency tracking loop, which is usually indispensable in coherent optical systems. The system works satisfactorily. The intermediate frequency can be arbitrarily tuned from about 400 MHz to 4 MHz.
Fabrication and characterisation of circularly birefringent helical fibres
- Author(s): R.D. Birch
- Source: Electronics Letters, Volume 23, Issue 1, p. 50 –52
- DOI: 10.1049/el:19870037
- Type: Article
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A technique for fabricating helical-core circularly birefringent fibres is reported. Extremely high levels of circular birefringence are achieved (B = 2.1 × 10-4 at 633 nm). Because of its unique structure, this fibre remains single-mode up to V values of 25.
Wide-bandwidth and high-power 1.3μm InGaAsP buried crescent lasers with semi-insulating Fe-doped InP current blocking layers
- Author(s): C.E. Zah ; J.S. Osinski ; S.G. Menocal ; N. Tabatabaie ; T.P. Lee ; A.G. Dentai ; C.A. Burrus
- Source: Electronics Letters, Volume 23, Issue 1, p. 52 –53
- DOI: 10.1049/el:19870038
- Type: Article
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The fabrication and performance of 1.3 μm InGaAsP buried crescent lasers with semi-insulating Fe-doped InP current blocking layers grown by MOVPE are reported. A modulation bandwidth above 8.3GHz has been achieved at room temperature without using a mesa-stripe geometry. CW output power up to 30 mW per facet at 20°C and CW operation up to 95°C have been obtained. The semi-insulating InP layer alone is proved to be an effective current blocking layer.
Microwave characterisation of 1 μm-gate AI0.48In0.52As/Ga0.47In0.53As/InP MODFETs
- Author(s): L.F. Palmateer ; P.J. Tasker ; T. Itoh ; A.S. Brown ; G.W. Wicks ; L.F. Eastman
- Source: Electronics Letters, Volume 23, Issue 1, p. 53 –55
- DOI: 10.1049/el:19870039
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We report microwave characterisation of nominally 1μm-gate AI0.48In0.52As/Ga0.47In0.53As (lattice-matched to InP) modulation-doped field-effect transistors (MODFETs). The AI0.48In0.52As/Ga0.47In0.53As MODFETs have room-temperature extrinsic transconductances as high as 250 mS/ mm. A room-temperature unity-current-gain cutoff frequency (fT) of 22 GHz and an fmax of 35 GHz were measured for a 1.2μm-gate MODFET.
Simple method for measuring hot-electron temperature in GaAs
- Author(s): Jiang Xiao-Song ; Yu Li-Sheng ; Wang Shu-Min ; Liu Hong-Xun
- Source: Electronics Letters, Volume 23, Issue 1, p. 55 –56
- DOI: 10.1049/el:19870040
- Type: Article
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A simple method is proposed to measure the hot-electron temperature, using an Au-GaAs Schottky barrier diode. The obtained temperature of electrons under the electric field of 500V/cm and 1100V/cm are 316K and 336K, respectively, while the samples are kept at room temperature.
Practical method of measuring reflection-induced power penalties in single-mode fibre transmission systems
- Author(s): W.C. Young ; L. Curtis ; N.K. Cheung ; S.J. Wang ; D.S. Burpee
- Source: Electronics Letters, Volume 23, Issue 1, p. 56 –57
- DOI: 10.1049/el:19870041
- Type: Article
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A simple method of measuring power penalties due to reflection effects on semiconductor lasers in single-mode fibre transmission systems has been developed using a dielectric thin-film-coated fibre endface together with a nearly reflection-free variable attenuator. Field measurements indicate that, for some 560Mbit/s systems, power penalties, resulting from a 15.9% reflection, could be as high as 1.9dB.
Phase-shifted diffraction-grating fabrication using holographic wavefront reconstruction
- Author(s): Y. Ono ; S. Takano ; I. Mito ; N. Nishida
- Source: Electronics Letters, Volume 23, Issue 1, p. 57 –59
- DOI: 10.1049/el:19870042
- Type: Article
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57
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A π-phase-shifted grating for a distributed-feedback laser diode with 1-2 μm phase-transition region has been fabricated by a new simple interference exposure method using a holographically reconstructed phase-shifted wavefront.
Narrowband digital voice communications over a meteor burst channel
- Author(s): J.R. Herman ; C.C. Duggan ; W.I. Thompson ; R.A. Costa ; D.M. Deluca
- Source: Electronics Letters, Volume 23, Issue 1, p. 59 –60
- DOI: 10.1049/el:19870043
- Type: Article
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We report the first successful narrowband digital transmissions of voice messages via meteor trail scatter propagation. A 12-word message, which took 6s to recite, was represented by a compressed data stream of 43 characters and required 86 ms for transmittal over the meteor scatter channel. The experiment used state-of-the-art speech recognition/digitisation equipment, a digital meteor burst communication system and a speech synthesiser.
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