By Topic

Quantum Electronics, IEEE Journal of

Issue 7 • Date July 1984

Filter Results

Displaying Results 1 - 20 of 20
  • [Front cover and table of contents]

    Publication Year: 1984 , Page(s): 0
    Save to Project icon | Request Permissions | PDF file iconPDF (204 KB)  
    Freely Available from IEEE
  • Analysis of mode behavior in a waveguide with graded index and gain

    Publication Year: 1984 , Page(s): 728 - 733
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (653 KB)  

    Numerical analysis has been carried out for a waveguide with graded index and gain. It is shown that the radiation peak of the fundamental mode is deflected as the gradient of either the index or gain increases. The high-order modes also change their peak intensity ratio as the gradient of index or gain increases. The behavior of the fundamental mode is suitable for use in a beam scanner while that of higher-order modes is suitable for use in a deflection switching of laser beams. The analysis also shows that the modal gain of higher-order modes becomes larger than that of the fundamental mode as the gradient of the index and gain increases, which provides some explanation for the wide laser beam scanning observed by Scifres et al. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An analysis of cleaved coupled-cavity lasers

    Publication Year: 1984 , Page(s): 754 - 764
    Cited by:  Papers (14)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1358 KB)  

    We present an analysis of (GaAl)As cleaved coupled-cavity (C3) lasers incorporating gain dependence on pumping and wavelength of both laser segments as well as the effects of spontaneous emission in the lasing diode section and the known dependence of file refractive index on carrier density. Our model allows us to analyze the physical origin of the experimentally observed variations in the lasing longitudinal mode number with the modulator laser section current. It also indicates a strong dependence of device behavior on the gap length and yields precise variations in threshold current with modulator current. In addition, the model predicts that in the vicinity of particular current values large (∼ 100 Å) wavelength shifts can be observed. These shifts could be useful in optical fiber communications multiplexing applications. Finally, results for C3lasers with sections of quite dissimilar length are presented and we note that these devices exhibit more erratic behavior than the lasers with sections of comparable length. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Difficulties associated with stimulated emission in a bismuth - Neon discharge

    Publication Year: 1984 , Page(s): 765 - 771
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (801 KB)  

    The population of the metastable 6p^{3} 2 D_{3/2}^{0} bismuth level has been determined by time-resolved absorption spectroscopy at times in the range 1-10 \mu s after the start of the discharge in a bismuth vaporneon mixture, for a neon pressure of 13 mbar and a specific discharge energy of 1 mJ . cm-3. An exponential decay of the population is observed and lifetimes of 3.0, 4.5, and 5.3 μs are obtained at temperatures of 830, 790, and 755°C, respectively. Measurements of the nine strongest fluorescent transitions to the metastable level confirm that a population of the order of 1013cm-3is established in the early stage of the discharge and exceeds by three orders of magnitude the peak population of the bismuth resonance level 6p^{2} 7s^{4}P_{1/2} . It is concluded that the absence of laser emission at 472.2 nm in the system studied is due to excessive population of the metastable level 6p^{3} 2 D_{3/2}^{0} during the early stage of the discharge. It is proposed that this high population arises from the dissociation of Bi2dimers by electron impact and that the loss of electron energy to dissociation and to excitation of the vibrational and rotational levels of the dimers is responsible for the very low population achieved in the 6p^{2} 7s 4 p_{1/2} level. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An efficient double-pass Raman amplifier with pump intensity averaging in a light guide

    Publication Year: 1984 , Page(s): 772 - 785
    Cited by:  Papers (10)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1905 KB)  

    Experimental observations on a double-pass methane Raman amplifier pumped by a KrF laser demonstrate efficient photon extraction (75-85 percent) of multiple pump pulses and high stage gain (10-20) with simultaneous intensity gain or "pulse compression" of about 2. The Stokes beam divergence is about 2.5 times the diffraction limit and is unchanged in the amplifier to within the precision of the experiment. The pump pulses are of poor spatial quality and propagate through the amplifier in a light guide. A simple one-dimensional theoretical model fits the results of the experiment. Analysis using the model permits a projection of the performance of very large final Raman amplifier-compressor stages for fusion laser systems. These systems, with somewhat better controlled pulse shapes than those used in the experiment, can deliver average intensity gains of 2-3 at a net energy conversion efficiency (all losses included) of about two thirds and a stage gain of 30. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Absorption and emission by atmospheric gases: The physical process

    Publication Year: 1984 , Page(s): 818
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (110 KB)  

    First Page of the Article
    View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • [Back cover]

    Publication Year: 1984 , Page(s): 0
    Save to Project icon | Request Permissions | PDF file iconPDF (513 KB)  
    Freely Available from IEEE
  • High-efficiency pulse compression with intracavity Raman amplifiers

    Publication Year: 1984 , Page(s): 786 - 796
    Cited by:  Papers (1)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1072 KB)  

    High-efficiency pulse compression using intracavity Raman amplifiers has been computed. The energy of a pump laser stored in a lossless cavity is extracted at the Stokes frequency by means of Raman amplification of an input Stokes pulse. Calculations are made for both long and short duration input Stokes pulses for different lossless cavities. As an example, we use a hydrogen-argon mixture as the Raman medium and 1.5 J/cm2energy fluence stored in the lossless cavity at the ruby frequency. By comparing amplified Stokes pulses to a 30 ns pulse duration conventional ruby laser delivering the same energy fluence, pulse shortening factors larger than 20 are computed with quantum conversion efficiencies higher than 80 percent. These values compare favorably to backward Raman amplification. Moreover, this technique is proved to be able to provide a pulse compression rate larger than 14, even for a broad-band laser, which is impossible with backward Raman amplification. This technique could be used with any laser, even with absorbing laser media (excimer lasers) provided pump energy is stored in the lossless cavity by shifting of the laser frequency with any nonlinear process. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Behavior of hydrogen molecules adsorbed on silica in optical fibers

    Publication Year: 1984 , Page(s): 694 - 697
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (416 KB)  

    It is shown that molecular hydrogen weakly adsorbed on silica in optical fibers has a dipole moment and is active in infrared spectra. This causes a loss increase at 1.3 and 1.55 μm, which are the attractive wavelengths for optical fiber communication systems. In addition, it is shown that the loss spectra are also related to the fundamental SiO4tetrahedral vibrations rather than the rotation of hydrogen molecules from the observation of the loss spectra in silica glass fibers containing hydrogen molecules and deuterium molecules. It is also shown that the loss is reversible and that the reversibility is promoted with temperature. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Degenerate four-wave mixing with surface guided waves

    Publication Year: 1984 , Page(s): 716 - 722
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (792 KB)  

    The theory of degenerate four-wave mixing with surface guided waves is developed and used to derive expressions for the non-linear cross sections. The relative merits of using planar thin film dielectric waveguides versus surface plasmons guided by metal surfaces are discussed, with specific numerical examples based on PTS and InSb. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Bifurcations in electrooptic bistable devices with short delay times in the feedback

    Publication Year: 1984 , Page(s): 690 - 693
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (616 KB)  

    We have investigated experimentally the behavior of a hybrid bistable electrooptic device with a delayed feedback when the delay time is comparable to the time constant of the device. The behavior is governed by a nonlinear difference-differential equation. The threshold of instability and the period of the oscillations observed close to threshold agree relatively well with the predictions obtained from a linear stability analysis of this equation. For larger input signals or feedback, bifurcations take place. We then observe period-2, period-4, and chaotic behavior following the period-doubling scheme of Feigenbaum. For delay times shorter than the time constant this bifurcation behavior can still be observed for large input signals. Furthermore, for such short delay times the threshold for onset of instabilities was observed to exhibit hysteresis, so different thresholds were observed when the input signal was increasing and decreasing. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Stabilization of single frequency operation of coupled-cavity lasers

    Publication Year: 1984 , Page(s): 733 - 744
    Cited by:  Papers (18)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1248 KB)  

    We present a theoretical analysis of cleaved coupled-cavity lasers. Mode selectivity arises from two mechanisms. The first is diffraction loss in the gap between the cleaved sections. The second is based on one section acting as a resonant reflector. Our analysis includes the change of refractive index with carrier density which shifts the cavity resonances and causes mode switching. Above threshold the gains g1and g2of the two cavities are not pinned, but are related for each mode in the form of a curve in the ( g_{1}, g_{2} ) plane. The separation of mode curves along a 45° line determines the ratio of mode intensities. Single mode operation above threshold is described by zones in the ( C_{1}, C_{2} ) plane where C1and C2are the currents driving the two cavities. Cases of stable, unstable, and bistable operation are discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Experimental and theoretical studies on colliding pulse mode locking

    Publication Year: 1984 , Page(s): 797 - 803
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (760 KB)  

    Experimental and theoretical studies on colliding-pulse mode locking (CPM) are presented. The equations of the theoretical model take into account all the orders in pulse energies and the results are calculated numerically. It is shown that the CPM laser has an asymmetric pulse shape which can be approximately expressed in terms of the "asymmetric hyperbolic secant" function, [\exp (-t/T_{1}) + \exp (t/T_{2})]^{-2} (T_{1} < T_{2}) . The experimental results on the pulse shape and pulse width of the CPM ring dye laser are compared to the numerical ones. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Low-power nonlinear Fabry-Perot reflection in CdHgTe at 10 µm

    Publication Year: 1984 , Page(s): 710 - 715
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (952 KB)  

    Measurements of the intensity dependence of CO2laser radiation reflected from a polished Cd0.23Hg0.77Te etalon at 77 K results in nonlinear features at power levels on the order of 1 mW, in good agreement with a theory which includes bandgap resonant nonlinearities and Auger carrier recombination. A high-reflectivity rear coating enhances these features, giving a characteristic which demonstrates differential optical gain. The effects of heating are discussed in this unusual case in which the electronic and thermal contributions to the intensity dependence have the same sign. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Frequency synthesized and continuously tunable IR laser sources in 9-11 µm

    Publication Year: 1984 , Page(s): 700 - 709
    Cited by:  Papers (6)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1448 KB)  

    A review of high-resolution microwave-tuned IR laser source with frequency-synthesized outputs exceeding 100 mW is presented. Details are given on system configuration, design parameters, tradeoff analysis, system optimization, and fabrication procedure, along with measured performance characteristics. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Gain and intervalence band absorption in quantum-well lasers

    Publication Year: 1984 , Page(s): 745 - 753
    Cited by:  Papers (116)  |  Patents (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1000 KB)  

    The linear gain and the intervalence band absorption are analyzed for quantum-well lasers. First, we analyze the electronic dipole moment in quantum-well structures. The dipole moment for the TE mode in quantum-well structures is found to be about 1.5 times larger at the subband edges than that of conventional double heterostructures. Also obtained is the difference of the dipole moment between TE and TM modes, which results in the gain difference between these modes. Then we derive the linear gain taking into account the intraband relaxation. As an example, we applied this analysis to GaInAs/InP quantum-well lasers. It is shown that the effects of the intraband relaxation are 1) shift of the gain peak toward shorter wavelength with increasing injected carrier density even in quantum-well structures, 2) increase of the gain-spectrum width due to the softening of the profile, and 3) reduction in the maximum gain by 30-40 percent. The intervalence band absorption analyzed for quantum-well lasers is nearly in the same order as that for conventional structures. However, its effect on the threshold is smaller because the gain is larger for quantum wells than conventional ones. The characteristic temperature T0of the threshold current of GaInAs/InP multiquantum-well lasers is calculated to be about 90 K at 300 K for well width and well number of 100 Å and 10, respectively. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Broad-band guided-wave electrooptic modulators

    Publication Year: 1984 , Page(s): 723 - 727
    Cited by:  Papers (18)  |  Patents (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (976 KB)  

    Lumped-element Mach-Zehnder interferometric modulators have been designed, fabricated in LiNbO3, tested and analyzed. These modulators had 3 dB bandwidths from 280 MHz to 2.75 GHz and Vπ's from 1 V to 4 V, respectively. A simple RLC equivalent circuit is utilized to model the packaged modulator performance and results are compared with those measured using a swept-frequency technique. The model is seen to break down at the higher frequencies due to a frequency-dependent resistance and the electrode and parasitic inductances are seen to limit the overall modulator performance. The effects of varying the electrode capacitance, resistance, or inductance on modulator performance are demonstrated. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High-power difference-frequency generation at 5-11 µm in AgGaS2

    Publication Year: 1984 , Page(s): 698 - 699
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (280 KB)  

    Efficient generation of high peak power and high average power difference-frequency radiation, continuously tunable over the range of 5-11 \mu m, has been achieved by mixing the Nd:YAG laser radiation with the output of an infrared dye laser pumped by the same Nd: YAG laser in AgGaS2. Peak pulse powers as high as 180 kW with an average power output of 14 mW were obtained around 6 μm. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Phase noise in a laser with output coupling

    Publication Year: 1984 , Page(s): 814 - 818
    Cited by:  Papers (18)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (496 KB)  

    An improved method of calculating the linewidth of a laser oscillator due to phase noise is proposed. The fluctuation in the output amplitude that leads to the phase diffusion is calculated as the amplified thermal and the quantum noise which are delta-correlated in time. The saturated gain distribution along the cavity axis that is consistent with the output coupling at the end surfaces is taken into account in calculating the amplification of the noises. The resulting linewidth formula differs somewhat from the conventional formula. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Phase and amplitude uncertainties in heterodyne detection

    Publication Year: 1984 , Page(s): 803 - 813
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1200 KB)  

    The quantum limits on simultaneous phase and squared-amplitude measurements made via optical heterodyne detection on a single-mode radiation field are established. The analysis proceeds from a fully quantum mechanical treatment of heterodyning with ideal photon detectors. A high mean field uncertainty principle is proven for simultaneous phase and squared-amplitude observations under the condition that the signal and image band states are independent, and the image band has zero mean. Operator representations are developed which show that no such principle applies when arbitrary signal/image band dependence is permitted, although the mean observations are no longer functions of the signal field alone. A multimode two-photon coherent state illustrating this behavior at finite energy is exhibited. Potential applications for the resulting improved accuracy measurements are briefly described. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

The IEEE Journal of Quantum Electronics is dedicated to the publication of manuscripts reporting novel experimental or theoretical results in the broad field of the science and technology of quantum electronics..

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Aaron R. Hawkins
Brigham Young University