Waveguide based electroabsorption modulator performance. Highspeed travelingwave electroabsorption modulators. This generation can be accounted for in the con tinuity equations 2 and 3 a coupling of the electrical section 2 and the optical system just mentioned can be realized this way. Some parts of the results in this presentation belong to nextgeneration highefficiency network device project, which photonics electronics technology research association petra contracted with new energy and industrial development organization nedo. Sep 30, 2005 a highspeed submount has been designed and fabricated for 40 gbs electroabsorption ea modulators. Dynamic extinction ratio as a function of driving voltage for 25gbits operation. As for 40g and 25g trans mitters, electroabsorption modulators. A low power 2x28 gb s electroabsorption modulator driver. The device has both a simple tuning scheme and a simple fabrication procedure, making it suitable for low cost massive production which is desirable for wdmpon uses. High speed electroabsorption modulator in the generic photonic integration platform m. An optical source is split and fed to each of the eams. The rc model of the eam can be extracted by fitting the s11 parameters of the equivalent circuit 6 shown in fig. The electroabsorptive modulation frequency is not limited by the relaxation frequency of the laser source and can go extremely high as long as the capacitance of the modulator is designed accordingly. Highspeed directly modulated lasers semantic scholar.
By applying bias on the material, the bandgap can be manipulated, and thus results in red shift of absorption spectrum. Electroabsorption modulator integrated distributed feedback laser. Oktyabrsky1 1co lleg eof nanos c asi nand e ngeer,u ny ab yba y tel5184378609, email. Highspeed directly modulated lasers tsuyoshi yamamoto fujitsu laboratories ltd. Particular embodiments may employ a single differential electrical driver supplying complementary positive and negative voltage signals to two respective eams. Low driving voltage bandfillingbased iiivonsilicon. Electroabsorption modulator nmechanisms franzkeldysh effect nobserved in conventional bulk semiconductors quantumconfined stark effect qcse nquantum well structures nboth of these electroabsorption effects are prominent near the bandgap of semiconductors. Embodiments are directed to a driver circuit for an electroabsorption modulator eam. Electroabsorptionmodulated widely tunable dbr laser. Electrooptic modulation is a key function for data communication. Leijtens 1 1 cobra research institute, eindhoven university of technology, p. Optical signal processing using electroabsorption modulators. Electroabsorption modulated laser how is electroabsorption modulated laser abbreviated. The modulation speed and transmission distance strongly depends on.
The cpw transmission line is designed to ensure low microwave loss and reflection, and ticuniau metal is adopted for electrode fabrication to guarantee good. High speed electroabsorption modulator in the generic. The ea modulator is driven with a voltage source device which is called vpulse and is located in the electrical library. Pmgi bridges are formed on both ends of the optical waveguide to connect grounds from dierent sides of the optical waveguide.
Silicon photonics platform for 50g optical interconnects cadence. Rp photonics encyclopedia electroabsorption modulators. Inside the silicon photonics transceiver mellanox community. In both types of devices, the absorption edge at room temperature is dominated by excitonic effects and can be strongly modi. The device provides a twowire serial interface which allows digital control of the modulation and bias currents, eliminating the need for external components. The feed line is 500 m long on each side of the optical waveguide. Chirp control of an electroabsorption modulator to be used. Javier romerovivas, aidan meehan and lukasz krzczanowicz optical communications research group, dept. Digital coherent transmitter using electroabsorption. Electroabsorption modulators based on bulk gan films and.
There is always a tradeoff between obtaining a low insertion loss in the onstate the transmissive state and getting a low modulation amplitude that is, the voltage modulation span. Oct 04, 20 for the love of physics walter lewin may 16, 2011 duration. The interaction of the modulator with the laser is analyzed and a requirement for. It is shown how the equivalent eam junction resistance is reduced with photocurrent to lower than 30. The demonstrated device has a compact active region of 1. We investigate the feasibility of an electroabsorption modulator integrated laser as a digital coherent transmitter. The driver tx the tia rx are the high speed electronics chips connecting the. Electronic and computer engineering, university of limerick, limerick, ireland. A low power 2x28 gbs electroabsorption modulator driver. Pam4 acceptable for long links, but nrz modulation preferred for short, latency sensitive links. Travelingwave electroabsorption modulators by shengzhong zhang the transmission bit rates in backbone telecommunication optical fibers are increasing rapidly, motivated by the explosive growth of internet traffic. Both manufacturers and distributors can be registered. Highpower 25gbs electroabsorption modulator integrated. A low power 2x28 gbs electroabsorption modulator driver array with onchip duobinary encoding renato vaernewyck y, xin yin, jochen verbrugghe, guy torfs y, xingzhi qiu, efstratios kehayasyy, nonmembers, and johan bauwelinckya, member summary an integrated 2x28 gbs dualchannel duobinary driver ic is presented.
A reasonable fit yields a junction capacitance of 10ff and series resistance of 110. Electroabsorption modulators based on bulk gan films and gan. Dec 01, 2014 the electroabsorption modulator eam is integrated into the device by the selectivearea growth sag technique. Simulation of saturation effects in electroabsorption.
Pmgi bridges are formed on both ends of the optical waveguide to connect grounds from di. Us98385b1 differential electroabsorption modulator. Low driving voltage bandfillingbased iiivonsilicon electroabsorption modulator qiangsheng huang,1,2 yingchen wu,2,3 keqi ma,1 jianhao zhang,1 weiqiang xie,2 xin fu,1,2 yaocheng shi,1 kaixuan chen,4 jianjun he,3 dries van thourhout,2 gunther roelkens,2 liu liu,4,a and sailing he1,4,a 1centre for optical and electromagnetic research, state key laboratory for modern optical instrumentation. Eml vs dml for datacenter and client side transceivers.
Development of electroabsorption modulator driver ics for 25 g. The ea modulator is driven with a voltage source device which is called vpulse and. The ea modulator device is located in the optoelectric library. The laser and eam sections are used as phase and amplitude modulators respectively.
Highspeed directly modulated lasers tsuyoshi yamamoto. Balanced electroabsorption modulator for highlinearity, lownoise microwave analog optical link f. Modeling of machzehnder and electroabsorption modulator. Highspeed coplanar waveguide based submount for 40 gbits.
Since the bw of the modulator is more than 50ghz, one can expect it to operate at data rates as high as 56gbps. As the channel bit rate distance product increases, external modulation of the laser light. Dc bias for the eams is provided at a common node in the middle. The modulator must exhibit great extinction ratio at 25g. An electroabsorption modulator or electroabsorption modulator is a semiconductor device which can be used for controlling modulating the intensity of a laser beam via an electric voltage intensity modulators.
Introduction external optical modulators are very important for optical fiber communication with highspeed modulation in digital and analog systems. Abstract the paper presents a new device for analog optical. Balanced electroabsorption modulator for highlinearity. An electroabsorption modulator or electroabsorption modulator is a semiconductor device which can be used for controlling modulating the intensity of a laser beam via. The external modulator exmod is modeled in terms of a small signal equivalent circuit model, as shown in figure 7. Emerging 100g transceivers for datacenter and client side applications fall into two different categories depending on the distance the information has to be transmitted, also termed reach, with each category using different optical technologies. While most papers report mach zehnder modulator mzm usage for odb 5, 6, in this research it was opted to use eams. Recent progress in electroabsorption modulator integrated distributed. Low driving voltage bandfillingbased iiivonsilicon electroabsorption modulator qiangsheng huang,1,2 yingchen wu,2,3 keqi ma,1 jianhao zhang,1 weiqiang xie,2 xin fu,1,2 yaocheng shi,1 kaixuan chen,4 jianjun he,3 dries van thourhout,2 gunther roelkens,2 liu liu,4,a and sailing he1,4,a. Ingangan quantum electroabsorption modulators with record. Electroabsorption modulated laser for long transmission spans. Dipartimento di elettronica, politecnico di torino, corso duca degli abruzzi 24, i10129 torino, italy. Electroabsorption modulator ii device configuration.
In the externally modulated links, the optical transmitter is based on a laser power source, typically a solidstate laser, such as ndyag followed by a machzehnder modulator or an electroabsorption modulator. With its voltageinduced electroabsorption modulator, neophotonics eml has a capability to operate more than 60gbps with a high reliability. By tamotsu kimura on september 30, 2015 leave a comment. Typically, the external modulator is a lithium niobate linbo 3 machzehnder type modulator hereinafter, ln modulator, or a modulator using a semiconductor electroabsorption effect hereinafter, ea modulator, and the ea. Ultraviolet electroabsorption modulators based on bulk gan. Development of electroabsorption modulator driver ics for 25g.
Monolithic integration of an electroabsorption modulator into a gaasbased duocavity vcsel for resonancefree modulation j. Where to buy electroabsorption modulators, eam, telecom. An eml is a laser diode integrated with an electroabsorption modulator eam in a. Onet11ec externally modulated laser driver with integrated. Optically controlled electroabsorption modulators for. The transmitter uses a quad md modulator driver and quad eml electroabsorption modulator laser with four dif ferent eml wavelengths. Sep 30, 2015 eml vs dml for datacenter and client side transceivers. G august 2004 information furnished by analog devices is believed to be accurate and reliable.
The modulation speed and transmission distance strongly depends. This includes drivers for high performance machzehnder modulators, externally modulated lasers eml and directly modulated lasers dml. Osa high speed gesi electroabsorption modulator at 1550 nm. An electroabsorption modulator eam is a semiconductor device which can be used for modulating the intensity of a laser beam via an electric voltage. In this paper, we outline newly developed ea modulator driver ics for both 25g and 40g transmission. The max3935 is designed to drive an electroabsorption modulator eam at data rates up to 10. However, no responsibility is assumed by analog devices for its use, nor for any infringements of patents or other rights of third parties that may result from. The 3 db small signal modulation bandwidth of the eam is over ghz. We discuss the challenges involved and demonstrate the combined phase and amplitude modulation on a commercial device. Coldren1 1unversity of california, santa barbara, ece dept. Modulator driver ics for 25g40g transmission sei tech. We have previously reported on the high modulation bandwidth of 25 ghz mea.
These ics have low power dissipation and highspeed. Electroabsorption modulator ii device configuration youtube. Chirp control to produce low or negative values of chirp at the output of an electroabsorption modulator eam is an important mechanism for reducing the signal degradation due to chromatic dispersion in highspeed transmission over standard singlemode fibre. Mellanox has developed an electroabsorption ea modulator also called franz. Given the vast amount of data handled, understanding the intricate physics and tradeoffs of modulators onchip allows.
Dfb with ea modulator laser diodes with an integrated ea electroabsorption type modulator achieve, type with integrated ea modulator package 10 nm dfb type part no. Chirpcontrolled tandem electroabsorption modulator. The submount contains a coplanar waveguide cpw for microwave signal feeding and a ta2n thinfilm resistor for impedance matching. Abstract high photocurrent effects in an electroabsorption modulator are explored using the high output power from an integrated sgdbr laser followed by semiconductor optical amplifier. Chirpcontrolled tandem electroabsorption modulator integrated with an soa and a sampledgrating dbr laser leif a johansson 1, yuliya a akulova2, greg a fish2 and larry a. A terminating impedance circuit, which is thermally decoupled from a substrate, for an electroabsorption modulator, having a modulator capacitance includes a series resistanceemphasized rf delay line exhibiting an impedance distributed over its length, wherein the spatially distributed impedance has at least a predominant resistance per unit length, an inductance per unit length tuned to the. We have demonstrated a travelingwave electroabsorption modulator based on the hybrid silicon platform.
It has 2 electrical ports for the bias and rf driving and 2 optical ports as an input and output. Macom has a large portfolio of optical modulator drivers for applications covering distances of hundreds of meters up to thousands of kilometers at data rates from 1 gbps up to 100 gbps and beyond. Wiedenhaus et al simulation of saturation effects in electroabsorption modulators fig. Electroabsorption modulator integrated light sources for future. The modulator has a broad operating wavelength range of 35 nm and a 3 db bandwidth of 40. Pdf 40gbs low chirp electroabsorption modulator integrated. Chirp compensation is demonstrated using voltage division to a longsection electroabsorption phase.
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