• Journal of information and communication convergence engineering
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• v.7 no.4
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• pp.556-560
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• 2009

We have investigated the spectral characteristics of semiconductor lasers locked to the external light injected from a modulated laser. study on FM sideband injection locking has shown that when SLs are locked to the target sidebands of the directly modulated ML, the presence of the unselected sidebands influences the resulting microwave signals. The unselected signals can produce the unwanted beat signals around the desired beat signal, which degrade the overall system performance. This analysis way to generate Giga HZ signal generation.

• Proceedings of the Optical Society of Korea Conference
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• 1989.02a
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• pp.214-217
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• 1989

The most attractive feature of semiconductor lasers as sources for coherent optical communication system is the ability to produce frequency modulation by modulation of the bias current. The frequency deviation of semiconductor lasers under direct modulation depends on the laser structure and modulation frequency. This paper describes a circuit modeling techniques for the directly frequency modulated CSP (Channeled Substrated Planner) semiconductor laser. Predictions from this model are compared with the other published results of sinusoidal frequency modulation below than 1 GHz.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.4
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• pp.811-815
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• 2005

We theoretically studied synchronization of chaotic oscillation in semiconductor lasers with chaotic light injection feed-back induced chaotic light generated from a master semiconductor laser was injected into a solitary slave semiconductor laser. The slave laser subsequently exhibited synchronized chaotic output for a wide parameter range with strong injection and frequency detuning within the injection locking scheme. We also analytically examined chaos synchronization based on a linear stability analysis from the view point of synchronization based on a linear stability analysis from the view point of modulation response of injection locked semiconductor lasers to chaotic light signal.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2004.05a
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• pp.66-69
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• 2004

We have investigated the spectral characteristics of semiconductor lasers locked to the external light injected from a modulated laser. The numerical model for semiconductor lasers under the external optical injection is based on the Lang's equation and has been extended in order to take into account the simultaneous injection of the multiple sidebands of the current-modulated laser. In this paper, we have analyzed characteristics of semiconductor laser using optical injection locking

• Proceedings of the Optical Society of Korea Conference
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• 1991.06a
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• pp.131-134
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• 1991

We describe the effects of additional feedback in external cavity semiconductor lasers, which are sensitive to feedback phase. It is shown that additional feedback with favorable phase can serve to enhance mode selectivity. The optimum feedback conditions to maximize the system immunity against unwanted additional feedback with unfavorable phase have also been determined.

• Journal of information and communication convergence engineering
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• v.8 no.4
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• pp.457-460
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• 2010

we have analyzed tens of Giga pulse signal generation using sideband injection locking scheme. The numerical model for semiconductor lasers under the strong optical injection is based on the Lang's equation and has been extended in order to take into account the simultaneous injection of the multiple sidebands of the current-modulated laser. The numerical simulation results show that the unselected sidebands will affect the optical and RF-spectral characteristics even though the semiconductor laser is locked to the target sidebands.

• Journal of the Optical Society of Korea
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• v.17 no.2
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• pp.117-129
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• 2013

We briefly review the recent progress in passively mode-locked fiber lasers (PMLFLs) based on semiconductor saturable absorber mirrors (SESAMs) and discuss the detailed characterization of a SESAM-based, passively mode-locked erbium-doped fiber (EDF) laser operating in the 1.5-${\mu}m$ spectral range for various configurations. A simple and compact design of the laser cavity enables the PMLFL to generate either femtosecond or wavelength-tunable picosecond pulses with high stability as the intra-cavity filtering method is altered. All the cavities investigated in our experiments present self-starting, continuous-wave mode-locking with no Q-switching instabilities. The excellent stability of the source eventually enables the wavelength-tunable PMLFL to be used as a master oscillator for a power-amplifier source based on a large-core EDF, generating picosecond pulses of >10-kW peak power and >100-nJ pulse energy.

• Korean Journal of Optics and Photonics
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• v.1 no.2
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• pp.191-197
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• 1990

An experiment on the phase stability of injection-locked beam is done by using AlGaAs semiconductor lasers. The coherence of two beams from the master and slave lasers is measured by interference between the beams in the Twymann-Green interferometer. The phase change of the output beam of the slave laser as a function of the driving current is measured in the Mach-Zehnder interferometer consisted of the master and slave lasers and a value of 2.5radlmA is obtainccl.

• Current Optics and Photonics
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• v.5 no.4
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• pp.384-390
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• 2021

This paper presents a wide-range tunable wavelength-locking technology based on optoelectronic oscillation (OEO) loops for optical fiber sensors and microwave photonics applications, explains the theoretical fundamentals of the design, and demonstrates a method for locking the relative wavelength differences between a leader semiconductor laser and its follower lasers. The input of the OEO loop in the proposed scheme (the relative wavelength difference) determines the radio-frequency (RF) signal frequency of the oscillation output, which is quantized into an injection current signal for feedback to control the wavelength drift of follower lasers so that they follow the wavelength change of the leader laser. The results from a 10-hour continuous experiment in a field environment show that the wavelength-locking accuracy reached ±0.38 GHz with an Allan deviation of 6.1 pm over 2 hours, and the wavelength jitter between the leader and follower lasers was suppressed within 0.01 nm, even though the test equipment was not isolated from vibrations and the temperature was not controlled. Moreover, the tunable range of wavelength locking was maintained from 10 to 17 nm for nonideal electrical devices with limited bandwidth.

• Journal of information and communication convergence engineering
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• v.4 no.3
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• pp.101-104
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• 2006

We have investigated the spectral characteristics of the semiconductor lasers locked to the sidebands of the master laser in this paper, which were expressed by a series of the Bessel function. The numerical model for the semiconductor lasers based on the typical Lang's equation has been extended in order to take into account the simultaneous injection of the multiple sidebands of the directly modulated ML. We analyses characteristics of direct intensity modulation.