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Laser diode

About: Laser diode is a research topic. Over the lifetime, 25062 publications have been published within this topic receiving 258956 citations. The topic is also known as: Diode laser & Semiconductor laser.


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Journal ArticleDOI
R. Lang1, Kohroh Kobayashi1
TL;DR: In this paper, the effects of external optical feedback on the semiconductor laser properties have been examined, i.e., return of a portion of the laser output from a reflector external to the laser cavity.
Abstract: Influences on the semiconductor laser properties of external optical feedback, i.e., return of a portion of the laser output from a reflector external to the laser cavity, have been examined. Experimental observations with a single mode laser is presented with analysis based on a compound cavity laser model, which has been found to explain essential features of the experimental results. In particular, it has been demonstrated that a laser with external feedback can be multistable and show hysteresis phenomena, analogous to those of non-linear Fabry-Perot resonator. It has also been shown that the dynamic properties of injection lasers are significantly affected by external feedback, depending on interference conditions between returned light and the field inside the laser diode.

2,462 citations

Journal ArticleDOI
TL;DR: In this article, the InGaN multi-quantum-well (MQW) structure was used for laser diodes, which produced 215mW at a forward current of 2.3
Abstract: InGaN multi-quantum-well (MQW) structure laser diodes (LDs) fabricated from III-V nitride materials were grown by metalorganic chemical vapor deposition on sapphire substrates. The mirror facet for a laser cavity was formed by etching of III-V nitride films without cleaving. As an active layer, the InGaN MQW structure was used. The InGaN MQW LDs produced 215 mW at a forward current of 2.3 A, with a sharp peak of light output at 417 nm that had a full width at half-maximum of 1.6 nm under the pulsed current injection at room temperature. The laser threshold current density was 4 kA/cm2. The emission wavelength is the shortest one ever generated by a semiconductor laser diode.

2,100 citations

PatentDOI
TL;DR: In this article, a II-VI compound semiconductor laser diode is formed from overlaying layers of material including an n-type single crystal semiconductor substrate (12), adjacent N-type and p-type guiding lasers (14), a quantum well active layer (18), and a second electrode (30) is characterized by a Fermi energy, with shallow acceptors having a shallow acceptor energy, to a net acceptor concentration of at least 1 x 1017 cm 3.
Abstract: A II-VI compound semiconductor laser diode (10) is formed from overlaying layers of material including an n-type single crystal semiconductor substrate (12), adjacent n-type and p-type guiding lasers (14) and (16) of II-VI semiconductor forming a pn junction, a quantum well active layer (18) of II-VI semiconductor between the guiding layers (14) and (16), first electrode (32) opposite the substrate (12) from the n-type guiding layer (14), and a second electrode (30) opposite the p-type guiding layer (16) from the quantum well layer (18) Electrode layer (30) is characterized by a Fermi energy A p-type ohmic contact layer (26) is doped, with shallow acceptors having a shallow acceptor energy, to a net acceptor concentration of at least 1 x 1017 cm-3, and includes sufficient deep energy states between the shallow acceptor energy and the electrode layer Fermi energy to enable cascade tunneling by charge carriers

1,453 citations

Book
31 Jul 1988
TL;DR: In this paper, the authors present the spectral properties of Fabry-Perot-type laser diodes with respect to light current, threshold current, and quantum efficiency, as well as the effect of nonlinear gain on spectral properties.
Abstract: 1 Introduction.- 2 Basic Laser Characteristics.- 2.1 Double heterostructure characteristics.- 2.2 Direct and indirect semiconductors.- 2.2.1 Energy- and momentum conservation.- 2.2.2 Semiconductor materials for direct and indirect semiconductors.- 2.3 Emission and absorption.- 2.3.1 Density of photon oscillation states.- 2.3.2 Principal mechanisms of radiative transitions.- 2.3.3 Carrier lifetime and lifetime of spontaneous emission.- 2.3.4 Gain and stimulated emission.- 2.4 Lasing characteristics of Fabry-Perot-type lasers.- 2.4.1 Lasing conditions.- 2.4.2 Dynamic characteristics of laser operation.- 2.4.3 Light current characteristics, threshold current and quantum efficiency.- 2.4.4 Basic laser structures.- 2.4.5 Modifications for the spontaneous emission term.- 2.5 Dynamic single-mode laser structures.- 2.5.1 DFB laser characteristics.- References.- 3 Longitudinal Mode Spectrum of Lasing Emission.- 3.1 Multimode rate equations.- 3.2 Spectral envelope for Fabry-1 Introduction.- 2 Basic Laser Characteristics.- 2.1 Double heterostructure characteristics.- 2.2 Direct and indirect semiconductors.- 2.2.1 Energy- and momentum conservation.- 2.2.2 Semiconductor materials for direct and indirect semiconductors.- 2.3 Emission and absorption.- 2.3.1 Density of photon oscillation states.- 2.3.2 Principal mechanisms of radiative transitions.- 2.3.3 Carrier lifetime and lifetime of spontaneous emission.- 2.3.4 Gain and stimulated emission.- 2.4 Lasing characteristics of Fabry-Perot-type lasers.- 2.4.1 Lasing conditions.- 2.4.2 Dynamic characteristics of laser operation.- 2.4.3 Light current characteristics, threshold current and quantum efficiency.- 2.4.4 Basic laser structures.- 2.4.5 Modifications for the spontaneous emission term.- 2.5 Dynamic single-mode laser structures.- 2.5.1 DFB laser characteristics.- References.- 3 Longitudinal Mode Spectrum of Lasing Emission.- 3.1 Multimode rate equations.- 3.2 Spectral envelope for Fabry-Perot-type lasers (linear gain).- 3.3 Influence of nonlinear gain on the spectral characteristics.- 3.3.1 Symmetric nonlinear gain.- 3.3.2 Asymmetric nonlinear gain.- 3.3.3 Nonlinear gain, conclusions.- References.- 4 Intensity-Modulation Characteristics of Laser Diodes.- 4.1 Modulation characteristics by studying single-mode rate equations.- 4.1.1 Turn-on delay.- 4.1.2 Rate equations, small signal analysis.- 4.1.3 Relaxation oscillation damping.- 4.1.4 Upper limits for the modulation bandwidth of laser diodes.- 4.2 Influence of lateral carrier diffusion on relaxation oscillation damping.- 4.3 Modulation bandwidth limits due to parasitic elements.- 4.4 Examples for high speed modulation of laser diodes.- 4.5 Modulation and longitudinal mode spectrum.- 4.5.1 Transient spectra of laser diodes.- 4.5.2 Lasing spectra under high speed modulation.- 4.5.3 Dynamic single-mode condition.- 4.6 Modulation with binary signals.- 4.7 Harmonic and intermodulation distortions (without fibre interaction).- 4.7.1 Harmonic and intermodulation distortions for low modulation frequencies.- 4.7.2 Harmonic and intermodulation distortions for high modulation frequencies.- References.- 5 Frequency-Modulation Characteristics of Laser Diodes.- 5.1 Relation between intensity-modulation and frequency modulation.- 5.2 Current/frequency-modulation characteristics.- 5.3 Chirp effects in directly modulated laser diodes.- 5.3.1 Spectral line broadening due to laser chirping.- 5.3.2 Chirp-reduction by proper pulse shaping.- 5.3.3 Time-bandwidth product of chirped pulses.- 5.3.4 Transmission of chirped pulses over single-mode fibres.- 5.4 Possibilities of modifying the chirp parameter ?.- 5.4.1 Dispersion of the chirp parameter ?.- 5.4.2 Chirp of laser diodes, coupled to optical cavities.- References.- 6 Instabilities and Bistability in Laser Diodes.- 6.1 Repetitive self-pulsations due to lateral instabilities.- 6.2 Instability and bistability in laser diodes with segmented contacts.- References.- 7 Noise Characteristics of Solitary Laser Diodes.- 7.1 Relative intensity noise (RIN).- 7.1.1 Basic properties of noise signals.- 7.1.2 Definition and measurement of RIN.- 7.1.3 Requirement of RIN for intensity modulated systems.- 7.2 Introduction of the spontaneous emission noise.- 7.3 Intensity noise of laser diodes.- 7.3.1 Intensity noise of laser diodes by studying single-mode rate equations.- 7.3.2 Mode partition noise.- 7.3.3 Mode partition noise analysis for nearly single-mode lasers.- 7.3.4 Mode-hopping noise.- 7.3.5 1/f-intensity noise.- 7.4 Statistics of intensity noise.- 7.4.1 Statistics of amplified spontaneous emission.- 7.4.2 Probability density distribution for the total laser light output.- 7.4.3 Statistics of mode partition noise.- 7.4.4 Turn-on jitter in laser diodes.- 7.5 Mode partition noise for the transmission of pulse-code modulated (PCM)-signals.- 7.5.1 Multimode lasers.- 7.5.2 The mode partition coefficient k.- 7.5.3 Nearly single-mode lasers.- 7.6 Phase and frequency noise.- 7.6.1 Phase and frequency noise characterization in general.- 7.6.2 Spectral line shape for white frequency noise.- 7.6.3 Spectral line shape for 1/f-frequency noise.- 7.6.4 Frequency noise and spectral linewidth for single-mode laser diodes.- 7.6.5 Power-independent contribution to the linewidth of laser diodes.- 7.6.6 Correlation between FM-noise and AM-noise.- References.- 8 Noise in Interferometers Including Modal Noise and Distortions.- 8.1 Noise in interferometers.- 8.1.1 Complex degree of coherence.- 8.1.2 Interferometric noise analysis for single-mode lasers.- 8.1.3 Interferometric set-ups for measuring the linewidth and the degree of coherence.- 8.1.4 Interferometric noise analysis for multimode lasers.- 8.2 Modal noise.- 8.2.1 Modal noise for monochromatic light sources.- 8.2.2 Modal noise for single-mode lasers with finite spectral linewidth.- 8.2.3 Modal noise for multimode laser diodes.- 8.2.4 Modal distortions.- 8.3 Modal noise and distortions in single-mode fibres.- References.- 9 Semiconductor Lasers with Optical Feedback.- 9.1 Amplitude and phase conditions for laser diodes with external cavities.- 9.1.1 Short external reflectors for longitudinal mode stabilization.- 9.1.2 Emission frequency shifts due to optical feedback.- 9.1.3 Single external cavity mode condition.- 9.1.4 Spectral linewidth for laser diodes with external optical feedback.- 9.2 Dynamics of laser diodes with external reflections.- 9.2.1 Derivation of the time-dependent electric field.- 9.2.2 Modulation characteristics of external-cavity lasers.- 9.3 Laser diodes with distant reflections.- 9.3.1 Classification of feedback regimes.- 9.3.2 Phase and frequency noise of laser diodes with distant reflectors.- 9.3.3 Intensity noise in laser diodes with distant reflectors.- 9.3.4 Coherence collapse.- 9.3.5 Tolerable feedback levels.- References.- 10 Laser Diodes with Negative Electronic Feedback.- 10.1 Modulation characteristics of laser diodes with negative electronic feedback.- 10.2 Linewidth narrowing and phase noise reduction with negative electronic feedback.- References.- 11 Circuitry for Driving the Laser Diode.- 11.1 Schemes for stabilizing the bias current.- 11.2 Laser drivers with optoelectronic integration.- References.

1,013 citations

Journal ArticleDOI
TL;DR: In this article, structural analysis was performed on a purple laser diode composed of In0.20Ga0.80N (3 nm)/In0.05Ga 0.95N (6 nm) multiple quantum wells.
Abstract: Structural analysis was performed on a purple laser diode composed of In0.20Ga0.80N (3 nm)/ In0.05Ga0.95N (6 nm) multiple quantum wells, by employing transmission electron microscopy and energy-dispersive x-ray microanalysis, both of which are assessed from the cross-sectional direction. It was found that the contrast of light and shade in the well layers corresponds to the difference in In composition. The main radiative recombination was attributed to excitons localized at deep traps which probably originate from the In-rich region in the wells acting as quantum dots. Photopumped lasing was observed at the high energy side of the main spontaneous emission bands.

850 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202338
2022105
2021301
2020536
2019610
2018569