Frequency conversion in semiconductor lasers and amplifiers. Theoretical and experimental studies of semiconductor. Semiconductor laser amplifiers as alloptical frequency. Semiconductor optical amplifiers soas, as the name suggests, are used to amplify optical signals. It is easy to show from our previous equation that the gain ripple is. Small edgeemitting laser diodes generate a few milliwatts or up to 0. To use, simply connect fiber patch cables with fcapc connectors to the input and output connectors and set the drive current and temperature with the dial on the front panel. An optical amplifier is a device that amplifies an optical signal directly, without the need to first convert it to an electrical signal. These lasers have some unique features compared to other types of mlls. Our optical amplifiers available in pigtailed butterfly packages include inpingaasp or gaasingaas semiconductor optical amplifiers boas or soas, and highspeed optical switches. Alan doolittle lecture 11d light emitting diodes and laser diodes reading. Highpower modelocked external cavity semiconductor laser using.
Optical amplifiers are devices that amplify an optical signal without converting it into an electric signal. These unique features make semiconductor mll suitable for a number of interesting applications, in particular, in the field of optical communications. Index termsoptical pulse amplification, semiconductor optical amplifier soa. The waveguide of the ridgesection of the tapered amplifier acts as a slit to capture the light of the seed laser. Fabrication and characterization of edgeemitting semiconductor lasers dr. Semiconductor optical amplifiers soas have proven to be versatile and multifunctional devices that are key building blocks for optical networks. As the power in the input signal is increased, there must be a power at which the amplifier gain decreases. The invention of the laser can be dated to the year 1958, with the publication of the scienti c paper infrared and optical masers, by arthur l. The power and gain specifications of our optical amplifiers can be further optimized for specific wavelength regions.
This post is going to help you get a better understanding of optical amplifier. Pdf semiconductor optical amplifiers and their applications. Boas and soas are singlepass, travelingwave amplifiers that perform well with both monochromatic and multiwavelength signals. These laser diodes are rugged and reliable, which allows me to use them in stateoftheart research experiments as well as educational projects. White paper introduction to optical amplifiers june 2010 1 introduction optical amplifiers are a key enabling technology for optical communication networks. Overview the new focus vamp ta7600 tapered amplifiers allow you to amplify the output power of a seed laser up to 2 w. There is a great variety of different semiconductor lasers, spanning wide parameter regions and many different application areas. Wavelength monitoring with semiconductor laser amplifiers. Liboironladouceur photonic systems group, department of electrical and computer engineering, mcgill university soa osa attenuator laser gain characterization ics laser soa osa attenuator the above characterization of a commercial soa, the kamelianopb1215, can. Mll mode locked laser based on quantum dots semiconductor modelocked lasers mll are the laser sources which can generate pulses in the optical domain.
In this masters thesis a diode laser amplifier with a gain of g4 is constructed. Lasing in tiltedwaveguide semiconductor laser amplifiers. Beneficiating from the actively modelocking operation and the wavelengthtunable characteristics of a fabryperot filter, different harmonic mode. Due to relatively low power production, these lasers are not suited to many typical laser applications. May 25, 2015 an optical amplifier is a device that amplifies an optical signal directly, without the need to first convert it to an electrical signal. Pdf the authors derive expressions for the small signal noise properties of the electrode current of a travellingwave semiconductor optical amplifier. The soa schematics are repeated below from the previous lecture. The amplifier output beam is used to pump two tunable optical parametric amplifiers. This study investigates the design of a lownoise optoelectronic amplifier channel suitable for a tof laser radar application. The experimental installation used in our study is schematically presented in fig.
All amateur radiorelated projects, tips, tricks, and tools. Koumans and raymond van roijen abstract we present a theory for passive modelocking in semiconductor laser structures using a semiconductor laser am. The heterostructure of the soa will first be modelled in harold, which will produce a set of material gain curves at different carrier densities. The low power consumption is also its great advantage. Semiconductor optical amplifiers fp laser inphenix. The basic working principle of an soa is the same as a semiconductor laser but without feedback. Erbiumdoped fiber laser erdoped fiber lasers edfls can be viewed as edfas operating in the particular regime where coherent oscillation of ase occurs due to some feedback means. A laser is an optical device that creates and ampli es a narrow and intense beam of coherent, monochromatic light. Laser stands for \light ampli cation by stimulated emission of radiation 7, 14.
They have a similar structure to fabryperot laser diodes but with antireflection design elements at the end faces. Erbiumdoped fiber amplifiers are the by far most important fiber amplifiers in the context of longrange optical fiber communications. For the love of physics walter lewin may 16, 2011 duration. In these applications, the laser is commonly connected to complex circuits to obtain the desired functionality. Optical communications technology is growing increasingly in importance, with a rapid pace of development. The amplifier is a doublepass semiconductor laser amplifier and the active region is 100 m broad. While in other laser materials like in gas lasers or solid state lasers, the processes associated. This optical gain is due to stimulated emission associated with light emission created by recombination of electrons and holes. First, mlls generating short pulses have been used for high bitrate optical transmission through optical timedivisionmultiplexing otdm. They form the backbone of the optical telecommunications infrastructure supporting the internet, and are used in information storage devices, barcode scanners, laser printers and many other everyday products. For improving optical output power of the laser mod ule, the polarization and the wavelength multiplexing were also used. Development of semiconductor laser for optical communication. Picwave can be used in combination with harold to model an semiconductor optical amplifier soa in the timedomain.
Semiconductor lasers types, applications, construction. The amplifier is operated at 793 nm using an external cavity diode laser as master laser. Otherwise the amplifier bandwidth is determined by cavity resonances. Optical amplifiers innolume high power laser diodes. Semiconductor optical amplifierbased alloptical gates. Characterization of semiconductor optical amplifiers. Semiconductor qswitched, shortpulse, highpower, mhz. After being filtered, the signal is processed by a decision circuit for data recovery. Characterization of semiconductor optical amplifiers m. Modulation characteristics of semiconductor lasers mod.
The former has tended to dominate conventional system applications such as inline amplification used to compensate for fibre losses. Longwavelength verticalcavity semiconductor optical. Integrating over a length z of amplifier medium gives the resultant optical power pz p0expgz. Oct 04, 20 for the love of physics walter lewin may 16, 2011 duration. The nonlinear behaviour of laser diodes integrated with. In semiconductor optical amplifiers soas, photons multiplied via stimulated emission. Simon, semiconductor laser amplifier for single mode optical fiber communications. This unique nested ring cavity enables high optical power to split into different branches where amplification and wavelength selection are achieved by using lowpower soas and a tunable filter. We have developed a novel optical fiber ring laser using a semiconductor optical amplifier soa as the gain medium, and taking advantage of polarization anisotropy of its gain.
In soas photons were confined in the dimensions transverse to the waveguide but were allowed to escape from the end of the waveguide. Pdf travelling wave semiconductor laser amplifier detector noise. Semiconductor optical amplifier soafiber ring laser and. Pout is the amplifier output power and pin the input power of a cw input signal. An optical amplifier may be thought of as a laser without an optical cavity, or one in which feedback from the cavity is suppressed. Amplifier mirror sampled grating tunable lasers5040302010 0 10 laser emission, dbm 0 0. Ultra linear quantumdot semiconductor optical amplifiers at 1. Simplified schematic illustrations of two types of laser amplifiers pump current active region ar antireflection coating ar signal in signal out a traveling wave amplifier a fabryperot amplifier. A novel technique for designing high power semiconductor. Soa semiconductor optical amplifier model simulation. Soas amplify incident light through stimulated emission. Semiconductor optical amplifier archives tutorials of fiber. Optical gain is the most important requirement for the realization of a semiconductor laser because it describes the optical amplification in the semiconductor material. For fttx, macom has the broadest portfolio of lasers, laser drivers, limiting amplifiers, photodiodes, and tias covering systems from gpon, epon to xgpon.
Davenport et al heterogeneous siliconiiiv semiconductor optical amplifiers 3100111 low 3% con. Wavelengthtunable 10 ghz actively harmonic modelocked. Thorlabs has integrated our fibercoupled optical amplifiers into easytouse benchtop units. This wafer process has formed the backbone of our manufacturing technology of semiconductor lasers. A booster amplifier is used to increase the optical output of an optical transmitter just before the signal enters an optical fiber. Extraction of semiconductor laser rate equation parameters. Depending on the initial detuning of the optical signal beam, both normal counterclockwise and reverse clockwise hysteresis are theoretically and experimentally obtained. Theory for passive modelocking in semiconductor laser. Fast and efficient dynamic wdm semiconductor optical amplifier. The high power laser module using this device shown in photo 1 was highly evaluated in the market. Stubkjaer invited paper abstract semiconductor optical amplifiers are useful building blocks for alloptical gates as wavelength converters and otdm demultiplexers. Feedback insensitive integrated semiconductor laser.
Testimonials i have been using laser diodes from qphotonics for several years in timeresolved luminescence experiments. When injecting an external signal into the optical amplifier of an integrated laser amplifier photonic circuit, the feedback from the laser may result in a strong nonlinearity that can be observed in the output power vs. Introduction to optical amplifiers 917 cannot exceed the pump power. Construction and design of a highpower doublepass laser.
Gaas quantum dot based photonic devices for direct modulation, mode. An optical amplifier may be considered as a laser without an optical cavity, or one in which feedback from the cavity is suppressed. Describe how a semiconductor laser diode works what determines the frequency that is emitted. Modulation characteristics of semiconductor lasers mod see. On the chip, two tunable laser pumps that are coherently injectionlocked, respectively, from two firstorder sidebands of an externally modulated tone are generated to enable signaldegenerate dualpumped phasesensitive amplification in a. Figure 1 shows three ways in which optical amplifiers can be used to enhance the performance of optical data links. Intensity noise and linewidth of laser diodes with integrated semiconductor optical amplifier article pdf available in ieee photonics technology letters 1412. White paper introduction to edfa technology june 2009 1 introduction shortly after their commercialization in the early 1990s, erbium doped fiber amplifiers edfas became a key enabling technology for optical communication networks, and have since comprised the vast majority of all optical amplifiers deployed in the field. Amphotonix offers a comprehensive portfolio of low cost semiconductor optical amplifier products for optical networking applications. The optical signal is attenuated as it travels in the optical fiber. To optimize the noise performance, the best preamplifier topology is selected and carefully optimized. Feedback insensitive integrated semiconductor laser the high purity of laser light is indispensable for applications ranging from telecommunications and metrology to health care.
A typical structure of a ingaaspinp soa is shown in the figure below. Experimental analysis shows that our technique achieves 31. We have designed a semiconductor optical amplifier integrated with an. Semiconductor optical amplifier based alloptical gates for highspeed optical processing kristian e. Advanced epitaxial wafer growth and optoelectronic packaging techniques enable a high output saturation power, low noise figure, and large gain across a broad. A semiconductor laser, using only a tapered amplifier as gain medium, is modelocked with a multiple quantum well saturable absorber and rf modulation, generating 0. In general, optical amplifiers can be divided into two classes. Ghafourishiraz, equivalentcircuit theory of spontaneous. Lm4250 programmable operational amplifier generaldescription the lm4250 and lm4250c are extremely versatile programmable monolithic operational amplifiers a single external master bias current setting resistor programs the input bias current input offset current quiescent power consumption slew rate input noise and the gainbandwidth product. The principles of semiconductor laser diodes and amplifiers. Digital library video clips, presentation files, etc. Single and multiple channel operation dynamics of linear. Products amphotonix semiconductor optical amplifiers. They are able to maintain spectral qualities of the seed laser while providing high and extremely stable power, making them ideal for high power applications.
Gain saturation is exhibited in the curves shown in figure 9. Pdf intensity noise and linewidth of laser diodes with. The technology of semiconductor amplifiers competes with that of erbiumdoped fiber amplifiers edfas. Dynamical properties of quantum dot semiconductor optical amplifiers. Rp photonics encyclopedia semiconductor lasers, laser diodes. Bistable switching of an optical signal beam by a control beam with a different wavelength, using the nonlinearity of a fabryperot semiconductor laser amplifier, is reported for the first time to the authors knowledge. The semiconductor optical amplifier soa is a polarization insensitive optical amplifier.
Together with wavelengthdivision multiplexing wdm technology, which allows the transmission of multiple channels over. A semiconductor optical amplifier is an optical amplifier based on a semiconductor gain medium. Verticalcavity semiconductor optical amplifiers vcsoas are interesting devices because of their small form factor, potential low manufacturing cost, high coupling efficiency to optical fiber, and polarization independent gain. Semiconductor optical amplifiers booster optical amplifiers are amplifiers which use a semiconductor to provide the gain medium. Runtime laser power management in photonic nocs with on. This thesis focuses on the development of a semiconductor laser fabricating process which utilizes semiconductor manufacturing technology in a. Alloptical frequency conversion of an optical data signal can be achieved by a travelingwave semiconductor laser amplifier over a spectral range given by its entire gain spectrum 1o thz. High power and high efficiency operation of semiconductor optical. Innovative optical devices have emerged from the integration of semiconductor laser diodes, amplifiers and filters with optical waveguide technology.
Experimental and theoretical results for the frequency conversion efficiency are presented. It is essentially like a laser diode where the end mirrors have been replaced with antireflection coatings. A ring fibre laser was used with a semiconductor optical amplifier soa as its active medium 7, 8. This paper presents experimental results of using an inverse bowtie gain guided semiconductor optical amplifier soa as the optical gain element in a hig.
We will briefly discuss the nature of this nonlinearity. The frequency difference of the bidirectional laser is controlled by birefringence which is introduced in the ring laser cavity. Introduction alloptical networks like extended reach cwdm based passive optical networks pon have a need for optical amplifiers. Since boas only amplify one state of polarization, they are best suited for applications where the input polarization of the light is known. Semiconductor lasers have important applications in numerous fields, including engineering, biology, chemistry and medicine. A semiconductor optical amplifier soa is essentially a laser diode ld with no feedback from its input and output ports and hence is also referred to as a travelingwave amplifier twa. White paper introduction to optical amplifiers finisar corporation. Semiconductor optical amplifier model file exchange. A simple, stable and inexpensive dualoutput port widely tunable semiconductor optical amplifier soabased fiber compoundring laser structure is demonstrated. Semiconductor qswitched, shortpulse, highpower, mhzrate laser alex dergachev, peter f. Thiswasfollowed by a more advanced version featuring a tapered mode converter.
Edfls are used as sources for coherent light signal generation, while edfas are used as wavewave amplifiers for. Optical bistability using a fabryperot semiconductor. Wavelength monitoring with semiconductor laser amplifiers a. The theory of nondegenerate fourwave mixing ndfwm in semiconductor lasers and amplifiers is presented with particular emphasis on the physical processes that lead to population pulsations. The range covers discrete semiconductor optical amplifiers through to soa arrays and ultimately highly functional hybrid modules. Introduction of optical amplifier tutorials of fiber optic. In doped fiber amplifiers and bulk lasers, stimulated emission in the amplifiers gain medium causes amplification of incoming light. When the light traveling through the active region, it causes these electrons to lose energy in the form of photons and get back to the ground state. Leisher the semiconductor laser was invented in 1962, and has recently become ubiquitous in modern life. Semiconductor laser diode outline this student project deals with the exam question semiconductor laser diode and covers the following questions. But the telecom market crash of 20002001 was a sufficiently massive blow to the market that the demand did not materialize, and most of. Semiconductor laser ii output characteristics youtube. The setup is much more compact, containing only a small semiconductor chip with electrical and fiber connections.