High frequency modeling for quantum-well laser diodes

Abstract

Citation: Gao J J. High frequency modeling for quantum-well laser diodes.High frequency modeling of quantum-well (QW) laser diodes for optoelectronic integrated circuit (OEIC) design is discussed in this paper. Modeling of the intrinsic device and the extrinsic components is discussed by accounting for important physical effects at both dc and high frequency. The concepts of equivalent circuits representing both intrinsic and extrinsic components in a QW laser diode are analyzed to obtain a physics-based high frequency model. The model is based on the physical rate equations, and is versatile in that it permits both small-and large-signal simulations to be performed. Several procedures of the high frequency model parameter extraction are also discussed. Emphasis here is placed on validating the model via a comparison of simulated results with measured data of the small-signal modulation response, obtained over a wide range of optical output powers.laser diode, quantum well, modeling, high frequency, small signal, large signal Since the success of injection type semiconductor lasers (laser diodes, LDs) in 1963, the feasibility study of using them as light sources for low-loss optical fiber communications has been a very important topic. Solid-state devices have become very reliable and taken the place of vacuum tubes in the microwave field. Actually, the most attractive feature of LDs is the easy modulation of light intensity only by varying the injection current, the so-called direct modulation. Conventional light-intensity modulators required high voltage and this resulted in high drive power or low modulation speed.The high-speed modulation potential of the semiconductor quantum-well (QW) lasers makes them promising candidates for high-bit-rate lightwave communication system. Semiconductor quantum-well lasers have low threshold current, high intrinsic modulation bandwidth, narrow linewidth, and large photon gain, and are important light sources for high-bit-rate lightwave communication system. A detailed analysis of the microwave operating characteristics of semiconductor lasers is crucial to the design of high-speed optical links.As we know, the electrical equivalent-circuit models for optical components are useful as they allow the existing, well-developed circuit simulators to be used in the design and analysis of optoelectronic circuits. A SPICE simulator was used to solve the equations because of its possibility of integrating with electrical components (laser driver, package parasitic, etc.).Traditionally, the microwave modulation response of the laser diodes was determined using a direct solution of the rate equations. This method of analysis has several disadvantages: It requires specialized software, it is not suitable for the inclusion of package parasitic, and device-circuit interactions are not easily taken into account. An alternative approach is to transform rate equations to equivalent circuit models including the electronic part and optical part. The corresponding dc, smallsignal, and large-sign...

A comprehensive consideration of bias voltage and temperature to extract the intrinsic frequency response of photodiodes

“…(iii) The parasitic parameters of the package network and the chip can be obtained by comparing with the results of packaged PD, and then with the equivalent circuit model of the whole PD can be established, consequently the comprehensive optimum design of the PD chip and its microwave packaging can be proceeded [16,17].…”

Characterization of high‐photocurrent and high‐speed INP‐based uni‐traveling‐carrier photodiodes at 1.55‐μm wavelength

“…The value of C dd can be determined using the procedure as follows . Setting initial value of C dd . Calculating the error as a function of the reflection coefficient at port 2: where is the error function criterion, superscript s denotes the simulated S‐parameter, m denotes the measured S ‐parameter, and i = (0… N−1) is the number of sampling points . If ε > ε 0 (ε 0 is the error target, normally 0.1%), the value of C dd needs to be updated to reduce ε. If ε < ε 0 is achieved, the value of C dd can be confirmed. …”

“…An accurate model parameter extraction technique of UTC‐PD is important for understanding of the device physical mechanisms and improving the device performances . Development of the equivalent circuit models of UTC‐PDs is also essential as it allows the existing well‐developed circuit simulation software to be utilized in the design and analysis of optoelectronic circuits . For high‐photocurrent and high‐speed photodiodes, various modeling methods, such as physics‐driven modeling, analytical modeling, empirical modeling and equivalent circuit modeling, have been investigated (especially for PIN‐PDs).…”

“…The accuracy of the results depends greatly on the parameters of the equivalent circuit model, thus a good equivalent circuit model is not merely helpful for prediction of the performances of devices but also important for extracting model parameters conveniently and accurately . Numerical optimization techniques are usually used to determine the optimal values of model parameters .…”

“…Numerical optimization techniques are usually used to determine the optimal values of model parameters . However, the accuracy of the optimization methods can vary largely up to the optimization method used and the initial values of model parameters selected . Nonphysical and nonunique results of the extracted parameter could be generated.…”