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Quantum Electronics, IEEE Journal of

Issue 10 • Date Oct. 2009

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Displaying Results 1 - 18 of 18
  • [Front cover]

    Page(s): C1
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    Freely Available from IEEE
  • IEEE Journal of Quantum Electronics publication information

    Page(s): C2
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    Freely Available from IEEE
  • Table of contents

    Page(s): 1211 - 1212
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    Freely Available from IEEE
  • Parameters for Quantitative Comparison of Two-, Three-, and Four-Level Laser Media, Operating Wavelengths, and Temperatures

    Page(s): 1213 - 1220
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (429 KB) |  | HTML iconHTML  

    Several parameters are proposed for describing the statistical thermodynamic component of the exchange of photons between a pump and a laser beam. They are based on the occupation probability of absorbing and emitting, pump and laser levels, and are complementary to the optical cross sections. The ldquooccupation factor,rdquo f 0 , is appropriate for describing an optical amplifier in the small signal regime. f 1 is appropriate for describing an amplifier in the large signal regime, e.g., a laser. They serve to facilitate a quantitative comparison of laser gain media, operating temperatures, and choice of pump and laser wavelengths. After a simple scaling, both occupation factors have a numerical value that coincides well, in most cases, with conventional usage of the terms two-, three-, and four-level laser. They can thus serve as an unambiguous, quantitative alternative to the quasi-two-, quasi-three-, and quasi-four-level terminology. The proposed definitions are general enough to apply to many types of gain media, but are particularly useful for comparing systems with discrete levels, pumped with a narrowband source, in near-resonance with the laser wavelength. Several low-quantum-defect combinations of pump and laser wavelengths are analyzed for Er3+ , Nd3+ , Yb3+ , and Ho3+ in YAG, as a function of temperature. View full abstract»

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  • Electronic Stabilization of Continuous-Wave and Pulsed Lasers Based on Macroscopic Rate-Equation Modelling

    Page(s): 1221 - 1231
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1059 KB) |  | HTML iconHTML  

    We present a macroscopic laser rate-equation model based on measurable laser parameters, allowing easy system identification. A numerical simulation based on the model is used in the design and testing of electronic laser feedback systems for intensity noise suppression and Q-switched pulse stabilization. A novel pulse energy control scheme is also presented, including experimental results. View full abstract»

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  • In Defence of the McCumber Relation for Erbium-Doped Silica and Other Laser Glasses

    Page(s): 1232 - 1239
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (189 KB) |  | HTML iconHTML  

    The reciprocity relation of McCumber which states that the emission and absorption spectra of broad solid-state laser transitions are related by the classical Boltzmann factor is critically examined. It is argued that it should be treated as an exact property of homogeneously broadened amorphous host gain media at room temperature. The contradiction between these conclusions and those of recent literature arguing against the applicability of the McCumber relation for erbium doped silica is resolved. Experimental support for the McCumber relationship in erbium doped silica fiber is provided. View full abstract»

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  • Optical Noise Tolerance in a Polarization-, Wavelength-, and Filter-Free All-Optical Clock Recovery System Based on a Monolithic Mode-Locked Laser

    Page(s): 1240 - 1247
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1173 KB) |  | HTML iconHTML  

    We experimentally investigated optical noise tolerance of a polarization-, wavelength-, and filter-free all-optical clock recovery system based on a monolithic mode-locked laser diode. The results showed that for input signal degradation, the jitter of the recovered clock did not degrade to approximately 8 dB/nm of the optical SNR. We also compared the clock recovery performance as functions of the wavelength and the modulation format (on-off keying and phase-shift keying) of the input data signals. We revealed that no significant changes were measured in the clock recovery performance despite such changes in the parameters of the input data signals, indicating that noise-tolerable clock recovery is expected, retaining the polarization- and the filter-free operations, regardless of the wavelength and the modulation format of the input data signals, by using our new scheme. View full abstract»

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  • Effective Noise Reduction by Electric Positive and Negative Feedback in Semiconductor Lasers

    Page(s): 1248 - 1254
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (520 KB) |  | HTML iconHTML  

    Semiconductor lasers tend to generate excess intensity noise called the optical feedback noise in addition to the quantum noise. A noise reduction method using an electric positive and negative feedback loop between an optical detector and a semiconductor laser was demonstrated in this paper. The electric positive feedback was set in a high-frequency region, reducing the optical feedback noise, while the electric negative feedback was set in a frequency range lower than the positive-feedback frequency, resulting in the suppression of the quantum noise (optical shot noise). Noise reduction over 100-MHz frequency region and a reduction ability superior to that obtained by the superposition of high-frequency current were confirmed. View full abstract»

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  • Corrugated Quantum-Well Infrared Photodetector Focal Plane Arrays

    Page(s): 1255 - 1264
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2566 KB) |  | HTML iconHTML  

    Corrugated quantum-well infrared photodetectors (C-QWIPs) have been proposed for long-wavelength infrared detection. In this work, we optimize the detector structure and produce a number of large format focal plane arrays (FPAs). Specifically, we adopt one-corrugation-per-pixel geometry to increase the active detector volume and incorporate a composite cover layer to preserve the large sidewall reflectivity, which results in a large detector quantum efficiency. We also optimize the detector material structure such as the final state energy, the doping density, and the number of quantum well periods to improve the FPA operation under the existing readout electronics. As a result, high FPA sensitivity has been achieved, and their characteristics are in agreement with the detector model. Based on this model, we perform a systematic analysis on the FPA performance with a wide range of detector and system parameters. We find that C-QWIP FPAs are capable of high-speed imaging especially for those with longer cutoff wavelengths. View full abstract»

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  • Threshold Temperature Dependence of a Quantum-Dot Laser Diode With and Without p-Doping

    Page(s): 1265 - 1272
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (235 KB) |  | HTML iconHTML  

    A study of the threshold characteristics of quantum-dot (QD) laser diodes shows how inhomogeneous broadening and p-doping influence the QD laser's temperature dependence of threshold T 0. The analysis includes the additional parameters of homogeneous broadening, quantum state populations, and threshold gain. The results show that while the source of negative T 0 can occur due to different effects, the transparency current plays a critical role in both undoped and p-doped QD lasers. Experimental trends of negative T 0 and their dependence on p-doping are replicated in the calculated results. Inhomogeneous broadening is found to play a lesser role to the transparency current in setting T 0. Homogeneous broadening is most important for uniform QDs with thermally isolated ground-state transitions. View full abstract»

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  • Theoretical Investigation of the Radiation Pattern From LEDs Incorporating Shallow Photonic Crystals

    Page(s): 1273 - 1283
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1048 KB) |  | HTML iconHTML  

    A theoretical approach based on coupled-mode theory is presented in order to determine the radiation pattern of LEDs incorporating a shallow photonic crystal. From this, a fundamental limit for the directionality of the diffraction of a single guided mode is given. Additionally, the Fabry-Perot resonances are shown to have significant impact on the directionality of diffracted light. For a realistic green-emitting InGaN LED in thin-film configuration the optimum reciprocal lattice vector is derived in terms of absolute diffracted intensity and directionality within a limited acceptance angle. The latter can be as high as 1.8 times the directionality of a Lambertian emitter. Furthermore, the spontaneous emission distribution between guided modes heavily influences the diffracted intensity. View full abstract»

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  • Position Effect of Spectral Filter on Properties of Highly Chirped Pulses in an All-Normal-Dispersion Fiber Laser

    Page(s): 1284 - 1288
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (591 KB) |  | HTML iconHTML  

    Numerical studies on the position effect of spectral filter (SF) in an all-normal-dispersion fiber laser are presented in this paper. The dependence of the available bandwidth range of the SF on its position in the laser cavity is investigated. Our simulation results suggest that the output pulses with high energy and strong peak power can be obtained when the SF with an appropriate spectral bandwidth is placed at the optimal positions in the laser cavity. View full abstract»

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  • Reducing ASE Effect in Coherent Detection by Employing Double-Pass Fiber Preamplifier and Time-Domain Filter

    Page(s): 1289 - 1296
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (447 KB) |  | HTML iconHTML  

    We report on a novel fiber based coherent detection system employing a double-pass fiber preamplifier, a spectral bandpass filter, and a time-domain filter. The time-domain filter, a synchronous time gate, reduces the in-band amplified spontaneous emission (ASE) beat noise, which cannot be achieved by the spectral bandpass filter alone. The double-pass fiber amplifier further reduces the out-band ASE by about 20 dB with a fiber Bragg grating (FBG) at the end of the fiber amplifier. In preliminary experiments with a 100 GHz bandpass filter, no degradation is observed from the optically preamplified coherent detection compared to pure coherent detection. With a 10 ns pulse width, 500 kHz repetition rate, and 10 pW average input power, about 2 dB and 1 dB signal-to-noise ratio (SNR) improvements are achieved when 5% and 50% time gating duty cycles are used, respectively. View full abstract»

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  • Analytical Solution of Band Gaps in 2-D Photonic Crystals Made by Multi-Beam Interference

    Page(s): 1297 - 1301
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (227 KB) |  | HTML iconHTML  

    Analytical solution of band gaps in two-dimensional (2-D) photonic crystals made by multi-beam interference was put forward. This solution gives concise analytical expression of every band gap. The quantitative relationship between the characters of band gaps and parameters of the materials of 2-D PC is different from that of one-dimensional (1-D) PC. For structures satisfying some conditions, the properties of band gaps obtained by the analytical solution are in good consistency with that obtained by the numerical simulations using plane wave expansion method. It showed why both TE and TM waves should have the same band structure in certain direction of 2-D PC with low refractive index. Also, it should be noted that the presented approach is accurate only for low index structures. View full abstract»

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  • Comment on “Theory and Experiment of {\hbox {In}}_{1-{x}}{\hbox {Ga}}_{x}{\hbox {As}}_{y}{\hbox {P}}_{1-{y}} and {\hbox {In}}_{1-{x}-{y}}{\hbox {Ga}}_{x}{\hbox {Al}}_{y}{\hbox {As}} Long-Wavelength-Strained Quantum-Well Lasers”

    Page(s): 1302
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (62 KB)  

    Minch [IEEE J. Quantum Electron., vol. 35, no. 5, pp. 771-782, May 1999] compared the theoretical conduction band offset ratio of In1-x-yGaxAlyAs/InP heterostructure calculated from Harrison's model and model-solid theory to the empirical results obtained from experimental measurement. We wish to point out that the comparison was not appropriate as the calculated results were the band offset ratio, whereas the reference empirical result was the band offset energy. The corrected comparison graph is presented in this comments. View full abstract»

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  • Special issue on very high throughput wireless over fiber technologies and applications

    Page(s): 1303
    Save to Project icon | Request Permissions | PDF file iconPDF (477 KB)  
    Freely Available from IEEE
  • Next-generation organic and hybrid solar cells

    Page(s): 1304
    Save to Project icon | Request Permissions | PDF file iconPDF (538 KB)  
    Freely Available from IEEE
  • IEEE Journal of Quantum Electronics information for authors

    Page(s): C3
    Save to Project icon | Request Permissions | PDF file iconPDF (26 KB)  
    Freely Available from IEEE

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