Engineered transfer function inp machzehnder modulator. In our measurement, the time delay is chosen such that. The transfer function of mz modulator is a sine wave function of the input voltage. Broadband linear silicon machzehnder modulators nanooptics. The operation of a mach zehnder interferometer is often used as an example in quantum mechanics because it shows a clear pathchoice problem. Design, fabrication and analysis of a machzehnder interferometer. We utilize various techniques to characterize the residual phase modulation of a waveguidebased mach zehnder electrooptical. Analysis and suppression of intermodulation distortion. A machzehnder modulator is used for controlling the amplitude of an optical wave. Osa linearized segmentation method for measuring the phase. The vertical axis shows the mzm output power and the horizontal axis shows the bias voltage. Inp integration of soamzis has been reported 1,2,3 and an. Dacx1416 optimized solution to modulator biasing in ratio.
Id like to point out again that the provided mfile is no runnable script. The incoming light is split into two branches, different phase shifts applies to each path, and then recombined. Consider a machzehnder modulator with two identical, nonideal phase. Maldonado department of electrical engineering the uni y ersity of texas at arlington arlington, texas 1 3. Here the thicknesses of the beamsplitters and the re. Bbs4 protocol by qpsk modulation using dualelectrode. This study provides experimental and analytical results showing an enhancement up to 20 db in the 3rdorder intermodulation distortion factor at 5 ghz using rf and optical asymmetrical feeding factors. Machzehndertype electrooptical intensity modulator c. We derive equations that quantify silicon machzehnder interferometer mzi modulator impact upon optical link budget for. Study theoretically and numerically the machzehnder interferometer optical filter which we use. Lastly, assume that the single photon consisting of only a single plane wave mode enters only one port of the beam splitter. Further, assume that the path lengths are identical.
Design, fabrication and analysis of a machzehnder interferometer user. More sophisticated version of the machzehnder interferometer diagram. Mach zehnder interferometer now assume that two 5050 beam splitters are in series, such that the outputs of one beam splitter are the inputs of the other beam splitter. Dec 20, 2016 the optical transfer function of a mach zehnder interferometer optical modulator is characterized by a raised cosine or sine transfer function. Mach zehnder modulator is used to control the amplitude of an optical wave. The intensity modulators are designed to have equal arms and thus balanced optical paths. The modulation may be imposed on the phase, frequency, amplitude, or polarization of the beam. Forward bias operation of silicon photonic mach zehnder modulators for rf applications rui lin chao,1,2 jin wei shi,1,3 aditya jain,1, takako hirokawa,1,4 akhilesh s. High speed silicon mach zehnder modulator ling liao, dean samararubio, michael morse, ansheng liu, dexter hodge intel corporation, sc12326, 2200 mission college blvd. Chapter 3 experimental study and optimization of oplls. Intensity distribution in the machzehnder modulator stacked xy slices finally, the power in each core can also be independently traced during a calculation. When the two arms are recombined, the phase difference between the two waves is. Integrated machzehnder modulator with two electrodes. External modulators and mathematical modeling ofmach zehnder.
Introduction to ixblue machzehnder modulators bias controllers. Silicon photonic machzehnder modulator architectures for. When biased at the correct point on the transfer function, this device can be used to combine. An electrooptic modulator eom is an optical device in which a signalcontrolled element exhibiting an electrooptic effect is used to modulate a beam of light. Bias controller of machzehnder modulator for electrooptic. The modulator enhances the bandwidth of the slow driving electronics at its input. A schematic representation of a machzehnder modulator made from waveguides with mismatched lengths where a portion of the waveguide is also a pn junction with an electrical voltage input left, and the optical transmission of the device as a function of wavelength on a log scale simulated with sparameters for two different bias voltage. The input waveguide is split up into two waveguide interferometer arms. If a voltage is applied across one of the arms, a phase shift is induced for the wave passing through that arm. In this figure, we imagine analyzing a candle flame. The machzehnder interferometer is frequently used in the fields of aerodynamics, plasma physics and heat transfer to measure pressure, density, and temperature changes in gases. The linearity is comparable to a reference lithium niobate mach zehnder interferometer modulator operating at quadrature and over an order of magnitude greater than silicon ring modulators based.
The semiconductor optical amplifier machzehnder interferometer soamzi wavelength converter is an important class of integrated wavelength converters that work for both rz and nrz data formats while also acting as a 2r signal regenerator due to their nonlinear transfer function. Waveguide linbo3 intensity modulators are machzehnder type interferometers. Vpi may also be referred to as the driving voltage of mzm 102 that is the voltage difference that induces the 1 and 0 of. Analysis of machzehnder interferometer with one arm loaded. This optical modulator can be coupled to a light source and a bias control module, which is configured to. As the electrooptic transfer characteristic of a mach zehnder modulator is cos2shaped, the modulator will be biased in the linear range between the maximum and minimum and the modulation signal will be superimposed onto the bias voltage. The dualelectrode machzehnder modulator demzm is an external electrooptic modulator that is widely used in radio over fiber rof systems to generate millimeterwaves mmwaves. Machzehnder interferometer the transfer function for a lossless, imbalanced i. However, there is always a small difference between the. The transfer function is just a diagonal matrix of exponentials. The corresponding transfer chart is depicted by black curve in fig.
How to simulate dual drive mach zehnder modulator in matlab. The technique based on combining a machzehnder modulator and a double. Two phase modulators can be placed in parallel using an interferometric structure. An optical iq modulator iqm including two parallel mach zehnder modulators mzm1, mzm2 generates single sideband data signals. Complex phase biasing of silicon machzehnder interferometer. A method for bias control of a nested mach zehnder mzi optical modulator that generates an optical quadrature amplitude modulated signal qam comprising. This application note aims to give intensity modulators users the basics to select and apply the proper rf and bias voltages to their device. As a device under test suitable to test the validity of the new rfscan method for the optical characterization of the spectral transfer function of devices both in amplitude and in phase, we will study the. By using a dualelectrode mach zehnder modulator for optical phase modulation, the assignment of the one of the. So far, ive heard that in mach zehnder interferometer, two output should have one constructive interference, and one destructive interference for other. You can achieve linear amplitude modulation with small modulation voltages by biasing the modulator at the 50% transmission point, either with a quarterwave plate or by applying a dc voltage to the modulator. The structure of the dualdrive mzm has two arms and electrodes. Machzehnder interferometer an overview sciencedirect topics. The linearity is comparable to a reference lithium niobate machzehnder interferometer modulator operating at quadrature and over an order of magnitude greater than silicon ring modulators based.
Meanwhile, a local oscillator source with a wavelengthadjustable. If we apply data and inverted data, the optical output will be chirp free, if we change the amplitudes of the driving signals the chirp can be adjusted. Gould department of physics university of connecticut storrs, ct 06269, usa phillip. A mzm consists of two phase modulators that change the speed of the light passing through them by changing the refractive index of the medium, proportional to an applied electrical signal. The output is a result of interference, ranging from. Depending on the relative phase acquired by the beam along the two paths the second beamsplitter will re. Performance analysis of rof link using machzehnder modulator. Pdf linearity characterization of a dualparallel silicon. Precise optical modulation using extinctionratio and. A linearity segmentation method for measuring the phase shift curve of silicon machzehnder modulators smzms as a function of applied electric field is presented.
Errorfree transmission of 23 gbs ook is achieved with driving electronics of 7. The optical wave enters from the input side and then splits equally into two arms. High speed silicon machzehnder modulator ling liao, dean samararubio, michael morse, ansheng liu, dexter hodge intel corporation, sc12326, 2200 mission college blvd. This is equivalent to integrating the location variable out of the voltage function. The transfer function of an amplitude modulator between crossed polarizers is a sin2 function. Machzehnder michelson sagnac interferometer fabryperot interferometer interferometers is an optical instrument that splits a wave into two waves using a beam splitter and delays them by unequal distances, redirect them using mirrors, recombine them using another beam splitter and detect the intensity of their superposition. In our measurement, the time delay is chosen such that fm function of wavelength on a log scale simulated with sparameters for two different bias voltage. Bias driver of the machzehnder intensity electrooptic modulator, based on harmonic analysis j. Us20090003840a1 controlling a bias voltage for a mach. Analysis of modulator linearity consider a machzehnder modulator with two identical, nonideal phase shifting sections placed into its arms, driven in a pushpull configuration see fig. This report summarizes the theoretical background, description and results of an experiment conducted in the optical communications and applied photonics laboratory. One way of implementing a mach zehnder modulator is a dual electrode structure or a push pull modulator. In the figure below, the blue curve represents the power in the arm located in the positive x region calculated over a circular area of the same extension as the waveguide core. The whole modulators transfer function hmzm at the.
Analysis of machzehnder interferometer with one arm. When such a splitter is placed at the second position in a particular way, the green light beam going to screen 1 will be suffering zero phase shift because it suffers a reflection coming from the denser medium and going back into the denser medium. Siliconorganic hybrid soh machzehnder modulators for. Linearized and high frequency electrooptic modulators thesis. Siliconorganic hybrid soh machzehnder modulators for 100. In this manuscript, we investigate the possible modifications to conventional machzehnder modulator structures to improve the system performance. Machzehnder modulator, intensity modulation, and mzm drift 1. The technique based on combining a mach zehnder modulator and a double. Machzehnder interferometer now assume that two 5050 beam splitters are in series, such that the outputs of one beam splitter are the inputs of the other beam splitter. As a device under test suitable to test the validity of the new rfscan method for the optical characterization of the spectral transfer function of devices both in amplitude and in phase, we will study the mach zehnder optical filter. The phase shifters are described by a voltagedependent phase. Off quadrature biasing of mach zehnder modulator for improved. When you use a real beamsplitter, it has a finite thickness.
Optical simulation of a machzehnder modulator beamlab. Machzehnder interferometer switch this lesson outlines the design process of an electrooptic 2. Such a modulator is called machzehnder intensity electrooptic modulator or simply machzehnder modulator mzm. Off quadrature biasing of mach zehnder modulator for. Versailles 433 185 121 siret 433 185 121 007 code ape 2651b n tva intra. Applying a small sinusoidal signal to the travelingwave electrode of the smzm, the upper and lower arms of the smzm produce differential phase modulation effect. On the performance of a linearized dual parallel mach. In our measurement, the time delay is chosen such that fm mach zehnder modulator is used to control the amplitude of an optical wave which is given to it. Zehnder modulator international journal of innovative science. Instead of multiplying exponentials, their arguments are summed.
The discussion presented in this chapter applies to any electrooptic material, any direction of the applied voltage, and any direction of the wave vector. This is a particular issue in siliconphotonics systems due to high power density, where high temperature variation is inevitable. Mach zehnder type electrooptical intensity modulator c. Introduction to machzehnder modulator bias controllers laser. Phase angle in order to minimize the unwanted harmonics and inter modulation components at the output of the machzehnder modulator. Analysis and suppression of intermodulation distortion effects in machzehnder modulator for analog optical transmission systems by. Abstractwe analyzed the complex transfer function and modulation spectrum of the machzehnder mz modulator with optical power and.
And a new modulator experiment was constructed and many aspects of the experimental apparatus were optimized. Phase angle in order to minimize the unwanted harmonics and inter modulation components at the output of the mach zehnder modulator. This work covers indium phosphide inp segmented machzehnder modulators. Forward bias operation of silicon photonic mach zehnder. This optical modulator can be coupled to a light source and a bias control module, which is configured to apply an offquadrature bias to the optical modulator. A mach zehnder modulator is used for controlling the amplitude of an optical wave. Bbs4 protocol by qpsk modulation using dualelectrode mach. Introduction to ixblue machzehnder modulators bias. But, what i had calculated above for the phase shift, doesnt fit with the argument above. The performance of a dual parallel differential machzehnder modulator broadband linearization architecture is analysed. Osa engineered transfer function inp machzehnder modulator. By varying the drive signals applied to the electrodes, i. External modulators and mathematical modeling ofmach. A 94 ghz antennacoupled directional coupler modulator was initially demonstrated using an old modulator chip from finbar sheehy.
An optical iq modulator iqm including two parallel machzehnder modulators mzm1, mzm2 generates single sideband data signals. Beam splitter inputoutput relations university of rochester. Osa linearized segmentation method for measuring the. The device is based on machzehnder interferometer made by titanium diffusion in lithium niobate substrate. A temperature independent driver for machzehnder modulators. Large signal analysis of machzehnder modulator intensity. Waveguide linbo3 intensity modulators are mach zehnder type interferometers. Monolithically integrated machzehnder interferometer. Large signal analysis of machzehnder modulator intensity response in a linear dispersive fiber j m b oliveira1. The second uses fabrication geometry and properties of the linearization technique to make a more robust modulator applicable to three of the modulators analyzed. The modulator is represented by its measured smallsignal transfer function, see c, followed by a cosineshaped intensity transfer characteristic as sketched in. A machzehnder modulator is used to control the amplitude of an optical wave which is given to it.
Iq or intensity mach zehnder supported modulation formats all, no dependency max. To obtain a chirp free signal the two drivers have to be very carefully matched option. The optical transfer function of a mach zehnder interferometer optical modulator is characterized by a raised cosine or sine transfer function. A control unit 18 generates additional optical single sideband pilot signals ps1, ps2 positioned in a lower and a higher sideband respectively, and also further pilot signals ps3, ps4 in both sidebands. An electrooptic switch is a device used in integrated fibre optics. Park har hotzvim, jerusalem, 91031, israel ulrich d. A 94 ghz antennacoupled directional coupler modulator was initially demonstrated using an. We utilize various techniques to characterize the residual phase modulation of a waveguidebased machzehnder electrooptical. However, the complexity of the transfer function makes it impossible to utilize the. Svarny t advances in robotics, mechatronics and circuits. A b source of photons 50% reflector 100% reflector figure 2. Four level pulse amplitude modulation pam4 has become the modulation format of choice to replace onoff keying ook for the 400 gbs short reach optical communications systems.
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