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Lightwave Technology, Journal of

Issue 10 • Date Oct. 1996

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Displaying Results 1 - 25 of 45
  • Multimedia transmission in fiber-optic LANs using optical CDMA

    Publication Year: 1996 , Page(s): 2149 - 2153
    Cited by:  Papers (46)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (489 KB)  

    In this paper, we address the problem of multimedia transmission in fiber-optic networks. We apply the code-division multiple-access (CDMA) technique for such a network. The necessary conditions for successful operation of the network are given. It is shown that for successful operation, new families of optical orthogonal codes (OOCs) are needed which will have not only good correlation properties within one code family, but also between families of different code lengths. Some possible constructions of multimedia OOCs and the corresponding basic structure of the receiver for the multimedia network are given. Specific examples of OOCs for the case of users with two different data rates are given, and the probability of error (using the Gaussian approximation) as a function of the number of low and high rate users is calculated. View full abstract»

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  • A novel Fourier technique for calculating fiber-to-LED coupling efficiency with lateral and longitudinal misalignments

    Publication Year: 1996 , Page(s): 2407 - 2413
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (616 KB)  

    Alignment tolerance is a very desirable quality for a low cost optical connector. Sensitivity to misalignment depends on a number of parameters such as emitter directivity, fiber core radius, fiber numerical aperture, and emitter size. In this paper, we present a novel Fourier technique to calculate the amount of power coupled into a large core fiber for various parameter values and longitudinal and lateral misalignments. This technique can be 100 times faster on a computer compared to the brute force numerical integration method. View full abstract»

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  • Dye-doped step-index polymer optical fiber for broadband optical amplification

    Publication Year: 1996 , Page(s): 2215 - 2223
    Cited by:  Papers (29)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (892 KB)  

    We report the development of a novel and simple technique for fabricating polymer optical fibers of good optical quality for special device applications. This technique aims at polymer fibers doped with various functional organic materials. On the basis of the technique, step-index polymer optical fibers doped with laser dyes have been fabricated. High-gain and high-efficiency optical amplification has been achieved in a Rhodamine B-doped polymer fiber with a low pump power of less 1 kW and pulse width 5 ns. Because a high dye concentration is used, the optimal wavelength range of optical amplification in this fiber is significantly red-shifted toward the center of the communication window (at 650 nm wavelength) of methyl methacrylate-based polymer optical fiber. The shift is from the originally 560 and 590 nm to presently 610 to 640 nm. We also present experimental results that show good photostability of the Rhodamine B-doped polymer fiber, compared with those recently reported in the improved polymer material systems. From the experimental observation, we identified the thermally induced bleach of dye molecules as the major contributing factor to the lifetime of our material system View full abstract»

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  • Effect of relatively strong light injection on the chirp-to-power ratio and the 3 dB bandwidth of directly modulated semiconductor lasers

    Publication Year: 1996 , Page(s): 2367 - 2373
    Cited by:  Papers (39)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (640 KB)  

    This paper describes a theoretical study of the small-signal modulation behavior of an injection-locked semiconductor laser. Illustrative examples are given, shelling a comparison between the free-running laser and the same laser with light injection. The results show that a substantial reduction of the chirp-to-power ratio (CPR) can be obtained, depending on both the injection level and the frequency detuning between the master and slave lasers. The behavior of the intensity modulation responses is also investigated, with the modulation conditions chosen in the dynamically stable locking range. It appears that the injection-locked laser may present a larger resonance frequency or modulation bandwidth with respect to those of the same laser under free-running operation View full abstract»

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  • Effect of optical amplifier noise on laser linewidth requirements in long haul optical fiber communication systems with Costas PLL receivers

    Publication Year: 1996 , Page(s): 2126 - 2134
    Cited by:  Papers (3)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (688 KB)  

    The impact of optical amplifier noise is analyzed in investigating the performance of optical long-haul PSK homodyne communication systems with Costas phase locked loop (PLL) receivers. The laser linewidth requirement for an optically amplified system becomes relaxed in comparison with the system with no optical amplifier, owing to the fact that the effect of incomplete phase tracking becomes less important as a larger signal power is demanded to maintain a fixed bit-error rate. Also, it is found that the power splitting ratio regarding the power distributions for the I-arm and the Q-arm of a Costas loop can vary in a wide range without having much influence on the performance of an optically amplified system. As a matter of fact, the power penalty induced by incomplete phase tracking for a system with a large number of cascaded optical amplifiers is mainly due to the finite phase error and not due to the power splitting ratio, and this may fail a previously-reported method for finding the required laser linewidth by assigning a certain amount of power penalty that is due to the power splitting ratio View full abstract»

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  • Interferometric noise reduction through intrabit frequency evolution of directly modulated DFB lasers

    Publication Year: 1996 , Page(s): 2117 - 2125
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (676 KB)  

    A new technique is demonstrated that improves the performance of optical networks subject to interferometric noise. Every transmitter comprises a selected DFB laser that is NRZ ASK directly modulated with a large modulation depth. Under modulation, the center frequency of the DFB laser is found to vary over the duration of each bit, falling during mark bits and rising during space bits with an exponential-like dependency of characteristic time constant ~20 ns. The optical frequency at the midpoint of each bit interval is not constant but depends upon the sequence of the preceding bits. Therefore, on the interference of a delayed-replica parasitic crosstalk waveform the interferometric noise generated on detection may be reduced by RF filtering according to the difference in center frequency of the interfering bits. This noise suppression which requires no additional hardware has been successfully modeled and experiment demonstrates little performance gain for a single interferer, as predicted. However, in the presence of multiple interferers significant improvement is predicted and observed at sub-Gb/s rates View full abstract»

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  • Performance of strained InGaAs/InAlAs multiple-quantum-well electroabsorption modulators

    Publication Year: 1996 , Page(s): 2324 - 2331
    Cited by:  Papers (10)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (712 KB)  

    The performance of a strained InGaAs/InAlAs multiple-quantum-well (MQW) electroabsorption (EA) modulator was evaluated theoretically and experimentally, The theoretical analysis showed that adding tensile strain to the InGaAs wells widens the wells and reduces the driving voltage; it also showed that adding compressive strain to the InAlAs barriers reduces the band discontinuities and increases the optical saturation power. A fabricated InGaAs/InAlAs MQW modulator with tensile strain in the wells and compressive strain in the barriers had a large modulation bandwidth (f3 dB>20 GHz) and a lower driving voltage (V15 dB=1.2 V) compared to an unstrained InGaAs/InAlAs MQW modulator, so it had a higher modulation efficiency (17 GHz/V). This strained MQW modulator produced a 10 Gb/s optical signal with a clear eye opening and small chirping (αeff=0.6). Moreover, it had shorter carrier escape times, so it has better optical saturation behavior. Introducing strain thus significantly improves the performance of the MQW-EA modulators View full abstract»

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  • A coaxial-type 1.3/1.55 μm WDM-PD module for optical access networks

    Publication Year: 1996 , Page(s): 2374 - 2381
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (684 KB)  

    A new 1.3/1.55 μm WDM/photodiode(PD) module has been designed and fabricated for use in optical access networks. A 1.3 μm-PD and a 1.55 μm-PD were arranged in series along the optical axis in a coaxial package. The 1.3 μm-PD with an In0.66Ga0.34 As0.76P0.24 photosensitive layer (λ g=1.42 μm) absorbs 1.3 μm digital optical signals and it is transparent to 1.55 μm wavelength. The 1.55 μm-PD with an In 0.53Ga0.47As photosensitive layer absorbs 1.55 μm analog optical signals. Responsivity of the module is 0.82 A/W at 1.31 μm wavelength and 0.75 A/W at 1.55 μm wavelength, respectively. IMD2 of the 1.55 μm-PD measured by two-tone method was -76.1 dBc at Pf(1.55 μm) of -6 dBm. Bit error rate (BER) of the 1.3 μm-PD was measured at 28.8 Mb/s by using an amplifier with bandwidth of 200 MHz and was found to be less than 10-8 at Pf(1.3 μm) of -30 dBm View full abstract»

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  • Fabrication of a pencil-shaped fiber probe for near-field optics by selective chemical etching

    Publication Year: 1996 , Page(s): 2231 - 2235
    Cited by:  Papers (32)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (664 KB)  

    We propose a novel method by chemical etching using hydrofluoric (HF) acid and a buffered HF solution (BHF) to fabricate a pencil-shaped fiber probe for near-field optics. We succeeded in producing such probes with high reproducibility using a dispersion-compensating fiber having the high GeO2 doped core. The method involves tapering of the cladding, then sharpening of the core. The fabricated probe has a conical tip with a cone angle of 20° and an apex diameter of less than 10 nm View full abstract»

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  • A completely packaged strictly nonblocking 8×8 optical matrix switch on InP/InGaAsP

    Publication Year: 1996 , Page(s): 2332 - 2337
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (640 KB)  

    We report the fabrication of a completely packaged (including electronic drivers) strictly nonblocking transparent optical 8×8 matrix switch for routing applications at wavelength 1.55 μm. The matrix is realized in a hybrid way from eight identical submodules each containing a single InP/InGaAsP chip with two 1×8 switches in parallel. The average values for fiber-matrix-fiber insertion loss and cross talk suppression are 20 and 28 dB, respectively. The usable wavelength range is 1450-1600 nm. The results indicate that large InP/InGaAsP switching matrices may be realized View full abstract»

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  • Transmission performance of high bit rate spectrum-sliced WDM systems

    Publication Year: 1996 , Page(s): 2141 - 2148
    Cited by:  Papers (51)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (612 KB)  

    We simulate transmission of a spectrum-sliced WDM channel operating at high bit rates (e.g., 622 to 2488 Mb/s). We calculate the bit error rate using the non-Gaussian statistics of thermal light sources that are commonly used in spectrum slicing and account for the effects of fiber dispersion. We evaluate the tradeoff in optical slice linewidth between signal-to-excess optical noise ratio and dispersion penalty in spectrum-sliced WDM systems, and determine the channel slicewidth that minimizes transmission penalty for a given link length and bit rate. We compare our simulations against the measured performance of a 1244 Mb/s channel over 20 km of fiber. The results in this paper provide useful information for the design of spectrum-sliced WDM networks View full abstract»

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  • Optical dispersion eigencompensators for high-speed long-haul IM/DD lightwave systems: computer simulation

    Publication Year: 1996 , Page(s): 2097 - 2107
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1140 KB)  

    This paper proposes what is believed to be the first linear optical dispersion-compensating technique capable of more effectively compensating for dispersively chirped signal than dispersively chirp-free signal. An effective digital eigen-filter approach is introduced for designing optical dispersion eigencompensators (ODECs) for compensation of the combined effects of laser chirp and fiber chromatic dispersion at 1550 nm in high-speed long-haul intensity-modulation direct-detection (IM/DD) lightwave systems. An integrated-optic synthesis of the ODEC using planar lightwave circuit (PLC) technology is proposed to enable high-speed signal regeneration. The proposed eigencompensating scheme is shown to result in the phenomenon of optical power enhancement: the combined effects of laser chirp, fiber chromatic dispersion and ODEC group delay can re-open the receiver eye further than the ideal eye-opening. The eigencompensating approach is shown to compare favorably with the Chebyshev filter technique in both the frequency and time domains View full abstract»

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  • Tunable LiF:F2- color center laser with an intracavity integrated-optic output coupler

    Publication Year: 1996 , Page(s): 2353 - 2355
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (280 KB)  

    A new LiF:F2- color center laser operation has been achieved by inserting a SiO2 thin-film waveguide in the laser cavity. The waveguide was deposited on LiF bulk crystal substrate with a holographic grating. The laser beam from the waveguide was tunable in 1150-1172 nm spectral range. The maximum ratio of the pulse energy of the laser radiation coupled out through the waveguide to that of the pump-radiation was 0.3%. The beam was stretched into the direction perpendicular to the waveguide plane, with a divergency of 7.2×10-2 View full abstract»

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  • A 1.5 Mb/s operation of a MARS device for communications systems applications

    Publication Year: 1996 , Page(s): 2382 - 2386
    Cited by:  Papers (6)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (492 KB)  

    We present the fabrication and performance of a Si MARS (mechanical antireflection switch) micromechanical optical modulator for fiber-in-the-loop applications. Device performance is reported showing rise and fall times of less than 100 ns, greater than 10 dB optical contrast ratio at ambient temperatures from -50 to 90°C, and evidence of reliability exhibited in operation at 500 kHz for over two months (two trillion cycles) without noticeable loss in performance. Bit error rate measurements show potential performance at 1.5 Mb/s with a 10 -9 bit error rate. Emphasis is placed on our efforts to produce a device which is practical, robust, and inexpensive to manufacture and package View full abstract»

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  • Distributed temperature sensing with erbium-doped fiber amplifiers

    Publication Year: 1996 , Page(s): 2236 - 2245
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (944 KB)  

    The experimental verification of a novel fiber-optic sensor which performs distributed measurement of temperature by using a distributed erbium-doped fiber amplifier (EDFA) is presented. The sensor configuration is similar to that of a conventional optical time-domain reflectometer and detects the Rayleigh backscattered portion of a pulsed optical signal which is amplified by the EDFA, along with the backward amplified spontaneous emission (ASE) generated by the EDFA. The sensor utilizes the temperature dependence of the gain in an EDFA. The amplification provided by the erbium-doped fiber, which is pumped at 1.48 μm, significantly increases the magnitude of the optical signal reaching the receiver, thus leading to a simplified configuration and a potentially superior performance as compared to other types of distributed fiber-optic temperature sensors View full abstract»

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  • Monolithic integration of MQW modulators on an optical multiplexer on InP for 100 Gb/s transmission

    Publication Year: 1996 , Page(s): 2344 - 2352
    Cited by:  Papers (9)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1048 KB)  

    We report on an InP-based optical multiplexer integrated with high-speed multiquantum-well (MQW) electroabsorption modulators for 100 Gb/s transmission. The optical multiplexer is based on a multimode interference (MMI) splitter, a waveguide array, and a taper-type combiner designed using the beam propagation method (BPM). The modulators are integrated on the top of the optical multiplexer. The integrated device is fabricated by three step epitaxy using metal organic vapor phase epitaxy (MOVPE) and by dry etching. The static and dynamic performances are measured, leading to the generation and the modulation of a 100 GHz optical pulse train. This optical pulse train is also coded using a pseudorandom nonreturn to zero (NRZ) pattern View full abstract»

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  • Polarization mode dispersion in a single mode fiber

    Publication Year: 1996 , Page(s): 2202 - 2208
    Cited by:  Papers (18)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (544 KB)  

    The Jones matrix method is used to measure the polarization mode dispersion (PMD) of a large variety of single mode fibers in the 1500 nm range. The dependence of PMD on wavelength, time, and temperature are studied in two different regimes: adiabatic and isothermal. In the adiabatic regime, time dependent stresses are introduced in the fiber by subjecting it to large and rapid changes in temperature. In this regime it is shown that the probability density function of PMD, obtained as a function of temperature and wavelength, fits very closely the theoretically predicted Maxwellian function. In the isothermal regime, the temperature of the fiber is held constant and the stresses are allowed to relax to their long term steady state conditions. In this regime the PMD exhibits a strong dependence on wavelength but otherwise is a bounded function which is nearly stationary with time. Test and analysis of the deterministic PMD in a specially constructed polarization maintaining fiber are used to study the dependence of PMD on temperature and wavelength. Finally, the system implications of this PMD study are described briefly View full abstract»

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  • New 2×2 and 1×3 multimode interference couplers with free selection of power splitting ratios

    Publication Year: 1996 , Page(s): 2286 - 2293
    Cited by:  Papers (35)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (816 KB)  

    We report on the concept and realization of new 2×2 and 1×3 multimode interference (MMI) couplers that offer the possibility of a free choice of the power splitting ratio. These MMI devices, using a new butterfly geometrical design, are compact, polarization-insensitive, and tolerant to fabrication parameters. Realized in InGaAsP/InP with large fabrication tolerances, they permit the control of the output powers within a few percentage points for both polarizations. The measurement results fit well the theoretical predictions. Extensions of the design are presented that assure a fully symmetrical geometry and therefore an optimal homogeneity of the device characteristics. Based on the same idea, a new compact mode converter-combiner is proposed View full abstract»

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  • High-accurate fault location technology using FSK-ASK probe backscattering reflectometry in optical amplifier submarine transmission systems

    Publication Year: 1996 , Page(s): 2108 - 2116
    Cited by:  Papers (4)  |  Patents (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (712 KB)  

    This paper proposes a new modulation format for optical time domain reflectometry (OTDR) to eliminate optical surge and improve OTDR performance in optical amplifier submarine transmission systems. The modulation format, FSK-ASK, uses a short high-power probe pulse and a long dummy pulse. Thanks to the slow gain dynamics of erbium-doped fiber amplifiers, both pulses experience an identical gain, equal to the loss of a span, so that the probe pulse maintains its high power and does not develop into an optical surge. Fault location experiments verify a theoretical prediction that FSK-ASK improves the signal-to-noise ratio (SNR) of OTDR by an amount as large as the power ratio of the probe to dummy signal. They also confirm the elimination of the optical surge caused by conventional OTDR using a solitary probe pulse. An FSK-ASK OTDR is applied in a commercial submarine amplifier transmission system which has a total transmission length of 890 km and a repeater spacing of 90 km. These field trial results show that subtle fiber anomalies can be located, with a spatial resolution of 1 km, along the entire length of the amplifier transmission system from a terminal end View full abstract»

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  • On the reference wave vector of paraxial Helmholtz equations

    Publication Year: 1996 , Page(s): 2395 - 2400
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (484 KB)  

    The reference wave vector for both scalar and vectorial formulations of the paraxial Helmholtz equation is determined by using various strategies which aim at the optimization of different features of the approximated solution. It turns out that all optimization schemes yield similar results, i.e., an overall optimization of the paraxial Helmholtz equation. A detailed analysis of a benchmark example shows that the reference wave vector must be adapted continuously during beam propagation. However, the required evaluation is so efficient that the additional numerical effort can be neglected View full abstract»

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  • Ultrafast photonic ATM (ULPHA) switch and a video distribution experiment

    Publication Year: 1996 , Page(s): 2154 - 2161
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (684 KB)  

    We describe the hardware implementation and experimental results for each function of our ultrafast photonic ATM (ULPHA) switch, which is an output buffer type ATM switch based on a time-division broadcast-and-select network. The hardware description focuses on the cell coder for generating ultrafast optical cells, the cell buffer with cell selection function, and the cell decoder for detecting ultrafast optical cells. Experiments demonstrate the generation and detection of 23 Gb/s, 4 b optical cells, including bit-error-rate measurements, and the operation of the cell buffer with the cell selector function. In a video distribution switching experiment, the switching of two time-division-multiplexed channels (25 Gb/s, 4 b optical cells) was achieved View full abstract»

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  • Optical path cross-connect system architecture suitable for large scale expansion

    Publication Year: 1996 , Page(s): 2162 - 2172
    Cited by:  Papers (11)  |  Patents (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1060 KB)  

    This paper proposes, for WPs (wavelength paths) and VWPs (virtual wavelength paths), a new OPXC (optical path cross-connect) architecture suitable for constructing large scale OPXC systems. The architecture is based on the multimodule concept and uses main modules and junction modules. The proposed OPXC is shown to provide triple the throughput of the conventional OPXC (delivery and coupling switch based) assuming state-of-the-art commercially available devices. It allows traffic demand increases to be supported with less OPXC switch hardware compared to the conventional OPXC architecture. The proposed architecture also keeps the advantages of the conventional architecture: a high level of expandability with regard to incoming/outgoing links and upgradability from a WP network to a VWP network. Thus the proposed OPXC architecture is highly flexible and allows minimum investment to encourage introduction while gracefully supporting future system scale expansion with incremental growth matching the traffic demand View full abstract»

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  • State-of-the-art aluminum-free 980-nm laser diodes

    Publication Year: 1996 , Page(s): 2356 - 2361
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (508 KB)  

    InGaAs/GaInAsP/GaInP ridge waveguide 980-nm laser diodes for pumping light into erbium doped fiber amplifiers are reviewed. These lasers have very good performance characteristics. They exhibit kink-free, single mode emission up to a power of 250 mW with a slope efficiency of 0.7 to 0.95 W/A, a thermally limited maximum power of 450-500 mW, and the threshold current density of about 150 A/cm2 . They are relatively stable against temperature variations. A 100 mW power from a fiber-pigtail module has been demonstrated. These lasers withstand severe thermal rollover tests without showing degradation effects. Preliminary lifetime tests indicate that their mean-time-to-failure (MTTF) may be very long, from several hundred thousand to one million hours, if not limited by sudden failure View full abstract»

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  • Normal mode analysis and characterization of an InGaAs/GaAs MQW field-induced optical waveguide including electrode effects

    Publication Year: 1996 , Page(s): 2422 - 2435
    Cited by:  Papers (5)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1556 KB)  

    An InGaAs/GaAs MQW field-induced optical waveguide of our design is described in this paper, and a theoretical electromagnetic analysis of the structure is presented. The device is an optical slab waveguide which can be switched to a buried optical guide having strong lateral and vertical optical confinement by means of a negative bias voltage applied to the overlaying Schottky contact electrode. The spatial distribution of the refractive index within the MQW region is determined for different bias voltages using a combination of experimental measurements that describe field-induced refractive index changes in the waveguide MQW core and a finite-difference representation of the static electric field generated by the electrode. The method of lines is then applied to characterize the optical modes that propagate in the structure for two bias voltages of interest. The electrode is included in the modal analysis via the free electron gas model which yields an equivalent negative permittivity for our aluminum metallization. We have determined that the effect of the metallization on the optical performance of our device is non-negligible. In particular, it has been found that the metallization itself supports guided modes and that it causes a reduction in the confinement and propagation constant of the optical modes guided by the device. Furthermore, these effects are polarization-dependent such that when losses in the MQW region and metallization are considered, the attenuation of power related to the vertically polarized mode is found to be 17 dB greater than the attenuation related to the horizontally polarized mode, implying that our field induced guide also acts as a polarization filter View full abstract»

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  • Modeling of a high frequency acousto-optic fiber phase modulator

    Publication Year: 1996 , Page(s): 2362 - 2366
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (440 KB)  

    The theory of a cylindrical acousto-optic phase modulator in the form of a thin ZnO film coated at the surface of a single mode optical fiber has been presented for high efficiency modulator design. The phase modulation at the frequency around 600 MHz with 15 dBm drive power was achieved in a simple acousto-optic device. The validity of acousto-optic modulator modeling is confirmed by experimental results. The device performance for various parameters has been theoretically investigated View full abstract»

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Aims & Scope

The Journal of Lightwave Technology contains articles on current research, applications and methods used in lightwave technology and fiber optics.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Peter J. Winzer
Alcatel-Lucent Bell Labs