44 results match your criteria linearity mach-zehnder


Linearity improvement of analog photonic link based on a phase-coherent orthogonal light wave generator.

Opt Lett 2021 Aug;46(15):3753-3756

This Letter presents a novel, to the best of our knowledge, linearized analog photonic link (APL) based on a phase-coherent orthogonal light wave generator that consists of a polarization-dependent Mach-Zehnder modulator (MZM) and a polarization controller (PC). By adjusting the PC and bias voltage of MZM, the third-order intermodulation (IMD3) terms can be suppressed while retaining a high gain for the fundamental terms, which indicates that the spurious free dynamic range (SFDR) of the proposed APL can be much improved. To further verify the feasibility of the proposed APL, a proof-of-concept experiment is performed, and the performances are compared with conventional APL. Read More

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Simultaneous measurement of temperature and curvature using ring-core fiber-based Mach-Zehnder interferometer.

Opt Express 2021 Jun;29(12):17915-17925

In this paper, the Mach-Zehnder interferometer (MZI) based on ring-core fiber was proposed and manufactured. Benefiting from the identical diameters of ring-core fiber, no-core fiber, and single-mode fiber, the MZI fiber sensor can be prototyped by sandwiching the ring-core fiber between the no-core fiber and the single-mode fiber (SMF). With the proposed specific structure of the ring-core fiber, the simultaneous measurement of temperature and curvature was achieved with the MZI sensor by means of monitoring the wavelength shift of interference dips. Read More

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Simple and precise characterization of differential modal group delay arising in few-mode fiber.

Opt Lett 2021 Jun;46(12):2856-2859

In this Letter, we propose a simple and high-precision differential modal group delay (DMGD) characterization method for few-mode fibers (FMF) by using the frequency-modulated continuous wave. Since the detected signals are located at the low-frequency range, our DMGD characterization method waives the use of expensive equipment, such as vector network or optical spectrum analyzers. Due to the high linearity of the used Mach-Zehnder modulator, our DMGD measurement is free from the complex auxiliary interferometer, leading to an improvement of characterization precision. Read More

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Temperature self-calibrated pH sensor based on GO/PVA-coated MZI cascading FBG.

Opt Express 2021 Apr;29(9):13530-13541

A temperature self-calibrated potential of hydrogen (pH) sensor based on the single mode fiber-tapered dual core photonic crystal fiber-single mode fiber (SMF-TDCPCF-SMF) structure cascaded with a fiber Bragg grating (FBG) is proposed and demonstrated. The TDCPCF structure formed Mach-Zehnder interferometer (MZI) is modified with a coating of graphene oxide/polyvinyl alcohol (GO/PVA) hybrid hydrogel to realize the measurement of pH, and the uncoated FBG is used to calibrate temperature. In our experiment, the sensitivity coefficient of 0. Read More

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Signal processing assisted Vernier effect in a single interferometer for sensitivity magnification.

Opt Express 2021 Apr;29(8):11570-11581

The Vernier effect magnifies optical sensitivity by the superposition of two spectra with slightly shifted frequencies from a sensing interferometer (SIM) and a reference interferometer (RIM). In this study, we demonstrate that the Vernier effect can be obtained through a single interferometer, which detects the changed signal and provides an artificial reference spectrum (ARS) to be superposed with the changed signal spectrum. The ARS extracted by spatial frequency down-conversion of one sensing spectrum in the signal processing is not affected by environmental changes and can be detuned at an arbitrarily small amount with the measured signal spectrum. Read More

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Highly linear wavelength-tunable microring-assisted Mach-Zehnder modulator.

Appl Opt 2021 Jan;60(2):250-256

This paper proposes a wavelength-tunable microring-assisted Mach-Zehnder modulator (MRAMZM) based on the graphene structure. The integrated graphene on the racetrack microring achieves the tunability of the working wavelength and introduces the one-cycle loss of the microring corresponding to the working wavelength. Through the analysis of the modulation characteristic curve with loss, it is determined to eliminate the second- and third-order nonlinearities. Read More

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January 2021

Axial strain applied in-fiber Mach-Zehnder interferometer for acceleration measurement.

Opt Express 2020 Jun;28(13):18596-18606

We present an axial strain applied in-fiber Mach-Zehnder interferometer (MZI) for acceleration measurement. A thin core fiber is sandwiched between two single-mode fibers with core offset to form the MZI. A controlled high fringe visibility in the transmission spectrum is obtained by applying an axial strain, leading to a large slope at the quadrature point. Read More

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High linearity silicon modulator capable of actively compensating input distortion.

Opt Lett 2020 Jul;45(13):3785-3788

In this Letter, we demonstrate an ultra-high linearity silicon carrier-depletion-based modulator by integrating a dual-parallel Mach-Zehnder modulator (DP-MZM) with a 1×2 thermo-optical switch. The operation principle is to manipulate power distributions of RF and optical signals among the two sub-MZMs, so their third-order nonlinearities can cancel each other. Spurious-free dynamic ranges (SFDRs) for the third-order intermodulation distortion (IMD3) are measured to be 123/120⋅ at 1/10 GHz, which represents a record-high linearity achieved with silicon-based modulators. Read More

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Linearized segmentation method for measuring the phase transfer function of a silicon Mach-Zehnder modulator by using the beat-frequency technique.

Appl Opt 2020 Apr;59(10):3255-3261

A linearity segmentation method for measuring the phase shift curve of silicon Mach-Zehnder modulators (SMZMs) as a function of applied electric field is presented. Applying a small sinusoidal signal to the traveling-wave electrode of the SMZM, the upper and lower arms of the SMZM produce differential phase modulation effect. Meanwhile, a local oscillator source with a wavelength-adjustable function is employed to heterodyne the intensity modulated optical signal of the SMZM; thus, the modulated intensity signal in the optical field domain is transformed into the low-frequency electric field domain. Read More

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Ultrasensitive refractive index sensor based on enhanced Vernier effect through cascaded fiber core-offset pairs.

Opt Express 2020 Feb;28(3):4145-4155

An ultrasensitive refractive index (RI) sensor based on enhanced Vernier effect is proposed, which consists of two cascaded fiber core-offset pairs. One pair functions as a Mach-Zehnder interferometer (MZI), the other with larger core offset as a low-finesse Fabry-Perot interferometer (FPI). In traditional Vernier-effect based sensors, an interferometer insensitive to environment change is used as sensing reference. Read More

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February 2020

High-performance fiber sensor via Mach-Zehnder interferometer based on immersing exposed-core microstructure fiber in oriented liquid crystals.

Opt Express 2020 Feb;28(3):3576-3586

Rapid technology development and various applications show great demands for high-quality temperature sensors with super-sensitivity, broad working temperature ranges, excellent linearity and high stability. Although tremendous efforts have been dedicated towards developing fiber sensors with high performance, challenges still remain in achieving all of the four parameters. Herein, we fabricate a fiber sensor via a Mach-Zehnder interferometer (MZI) combined with a liquid crystal (LC)-filled microtube, where the LC in the microtube is uniformly orientated. Read More

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February 2020

Up-down Taper Based In-Fiber Mach-Zehnder Interferometer for Liquid Refractive Index Sensing.

Sensors (Basel) 2019 Dec 10;19(24). Epub 2019 Dec 10.

Key Lab of Electronics Engineering, College of Heilongjiang Province, Heilongjiang University, Harbin 150080, China.

A novel in-fiber Mach-Zehnder interferometer based on cascaded up-down-taper (UDT) structure is proposed by sandwiching a piece of polarization maintaining fiber between two single-mode fibers (SMF) and by utilizing over-fusion splicing method. The dual up tapers respectively act as fiber splitter/combiner, the down taper acts as an optical attenuator. The structure parameters are analyzed and optimized. Read More

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December 2019

Silicon dual-series Mach-Zehnder modulator with high linearity.

Opt Lett 2019 Dec;44(23):5655-5658

In this Letter, we demonstrate a highly linear silicon modulator based on the dual-series Mach-Zehnder modulator (MZM) architecture. The two sub-MZMs are biased at quadrature points of opposite polarities. A proper power-splitting ratio of the driving RF signal on the two sub-MZMs enables the suppression of the third order intermodulation distortion (IMD3). Read More

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December 2019

Two-mode fiber based directional torsion sensor with intensity modulation and 0° turning point.

Opt Express 2019 Sep;27(20):29340-29349

In this paper, we report a novel in-fiber Mach-Zehnder interferometer based directional torsion sensor, in which a section of two-mode fiber is sandwiched between two single mode fibers by over core-offset splicing technique. The variety of fringe visibility demonstrates the strong dependence on offset and fiber length. For the first time the near zero visibility at 0° rotating state is obtained by fine offset-modulation. Read More

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September 2019

Integrated photonics interferometric interrogator for a ring-resonator ultrasound sensor.

Opt Express 2019 Aug;27(16):23408-23421

We present a compact integrated photonics interrogator for a ring-resonator (RR) ultrasound sensor, the so-called MediGator. The MediGator consists of a special light source and an InP Mach-Zehnder interferometer (MZI) with a 3 ×3 multi-mode interferometer. Miniaturization of the MZI to chip size enables high temperature stability and negligible signal drift. Read More

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Hydrogen sulfide gas sensor based on copper/graphene oxide coated multi-node thin-core fiber interferometer.

Appl Opt 2019 Mar;58(9):2152-2157

A hydrogen sulfide gas sensor based on a copper/graphene oxide (Cu/GO) coated multi-point thin-core fiber Mach-Zehnder interferometer is proposed and experimentally demonstrated. The single-mode fiber (SMF) is sandwiched between the thin-core-fiber-1 (TCF-1) and thin-core-fiber-2 (TCF-2), and the SMF-TCF-1-SMF-TCF-2-SMF Mach-Zehnder interferometer is obtained. In order to detect the concentration of hydrogen sulfide, Cu/GO composite sensitive film was coated on the outside surface of two thin-core fibers. Read More

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Transparent intersatellite optical wireless communication link with double sideband-suppressed carrier modulation and coherent homodyne detection.

Authors:
Kang Zong

Appl Opt 2018 Nov;57(31):9464-9470

In this paper, we present an intersatellite optical wireless communication (IsOWC) link with double sideband-suppressed carrier (DSB-SC) modulation and coherent homodyne detection (CD), which enables transparent transport of multiband radio frequency (RF) signals. The performance of transparent multiband IsOWC link employing DSB-SC/CD and phase modulation with CD (PM/CD) is investigated. The theoretical model considers the finite extinction ratio (ER) of a Mach-Zehnder modulator (MZM) and the saturation property of an optical booster amplifier. Read More

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November 2018

Compact optical fiber temperature sensor with high sensitivity based on liquid-filled silica capillary tube.

Appl Opt 2018 Feb;57(5):1061-1066

We propose a highly sensitive fiber temperature sensor based on a section of liquid-sealed silica capillary tube inserted in a single-multi-single-mode fiber structure. The liquid polymer is filled into the silica capillary tube through two micro-holes drilled by a femtosecond laser. Then the micro-holes are blocked by UV curable adhesive with ultra-small volume. Read More

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February 2018

Digitally controlled multiplexed silicon photonics phase shifter using heaters with integrated diodes.

Opt Express 2017 Nov;25(24):29778-29787

We present a silicon side heater with integrated diode to provide multiplexed control of different elements in a photonic circuit based on the polarity of the driving signal. The diode introduces an asymmetric electrical response where the heater is only active under forward bias. This can be used to address multiple heaters through the same electrical electrical contacts. Read More

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November 2017

Optical PAM-4 signal generation using a silicon Mach-Zehnder optical modulator.

Opt Express 2017 Sep;25(19):23003-23013

An analytic model is proposed to study the linearity performance of the silicon Mach-Zehnder optical modulator. According to the simulation results, we optimize the width of the silicon rib waveguide and the location of the PN junction to improve the linearity performance. The fabricated silicon Mach-Zehnder optical modulator has a spurious free dynamic range of 113. Read More

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September 2017

High-quality Mach-Zehnder interferometer based on a microcavity in single-multi-single mode fiber structure for refractive index sensing.

Appl Opt 2017 Feb;56(4):847-853

A fiber inline Mach-Zehnder interferometer (MZI) based on a microcavity with two symmetric openings in single-multi-single mode fiber (SMSF) structure is proposed. By using the finite difference beam propagation method (FD-BPM), the interference spectrum simulation result shows that the MZI can still have high-quality interference even if the microcavity deviates along the radial direction for 3 μm. Therefore, it allows a larger fabrication tolerance and tremendously decreases the fabrication difficulty. Read More

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February 2017

Fast label-free detection of C-reactive protein using broad-band Mach-Zehnder interferometers integrated on silicon chips.

Talanta 2017 Apr 3;165:458-465. Epub 2017 Jan 3.

Immunoassay/Immunosensors Lab, Institute of Nuclear & Radiological Sciences & Technology, Energy & Safety, NCSR "Demokritos", Aghia Paraskevi, Greece.

An immunosensor for fast and accurate determination of C-reactive protein (CRP) in human serum samples based on an array of all-silicon broad-band Mach-Zehnder interferometers (BB-MZIs) is demonstrated. The detection was based on monitoring the spectral shifts during the binding of CRP on the antibody molecules that have been immobilized on the sensing arms of the BB-MZIs. By employing the reaction rate as the analytical signal the assay time was compressed to few minutes. Read More

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Envelope-based technique for liquid level sensors using an in-line fiber Mach-Zehnder interferometer.

Appl Opt 2016 Dec;55(34):9803-9809

This paper proposes a sensor interrogation technique based on the analysis of the overall spectrum envelope of an in-line Mach-Zehnder interferometer structure with three different fibers. The interference pattern created by a level sensor of 120 mm was evaluated with both the traditional and the proposed interrogation techniques. The result shows that the technique here proposed improves the sensitivity of the sensor by more than an order of magnitude. Read More

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December 2016

Highly linear dual ring resonator modulator for wide bandwidth microwave photonic links.

Opt Express 2016 Nov;24(24):27268-27279

A highly linear dual ring resonator modulator (DRRM) design is demonstrated to provide high spur-free dynamic range (SFDR) in a wide operational bandwidth. Harmonic and intermodulation distortions are theoretically analyzed in a single ring resonator modulator (RRM) with Lorentzian-shape transfer function and a strategy is proposed to enhance modulator linearity for wide bandwidth applications by utilizing DRRM. Third order intermodulation distortion is suppressed in a frequency independent process with proper splitting ratio of optical and RF power and proper dc biasing of the ring resonators. Read More

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November 2016

Method to improve the linearity of the silicon Mach-Zehnder optical modulator by doping control.

Opt Express 2016 Oct;24(21):24641-24648

We optimize the linearity performance of silicon carrier-depletion Mach-Zehnder optical modulator through controlling the doping concentration. The optical field distribution in the waveguide is a Gaussian-like distribution. As the doping concentration increases, the dynamic depletion width of the PN junction under the same modulation signal will decrease, and the integration width of the overlap between the Gaussian-like optical field distribution and the depletion region will become smaller. Read More

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October 2016

[Refractive Index Insensitive Temperature Sensor Based on Cascading Single Mode Fiber with Few Mode Fiber].

Guang Pu Xue Yu Guang Pu Fen Xi 2016 Nov;36(11):3726-31

A refractive index insensitive temperature sensor is proposed base on cascading single mode fiber with few mode fiber(FMF). During the sensor preparation, the splicing current is set to 100 mA, and a section of FMF is no core-offset splicing between two single-mode fibers. Therefore, it can motivate the transmission mode preferably and form optical fiber Mach-Zehnder interferometer. Read More

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November 2016

All-optical single-sideband frequency upconversion utilizing the XPM effect in an SOA-MZI.

Opt Express 2016 Sep;24(18):20309-17

An all-optical single sideband (OSSB) frequency upconverter based on the cross-phase modulation (XPM) effect is proposed and experimentally demonstrated to overcome the power fading problem caused by the chromatic dispersion of fiber in radio-over-fiber systems. The OSSB frequency upconverter consists of an arrayed waveguide grating (AWG) and a semiconductor optical amplifier Mach-Zehnder interferometer (SOA-MZI) and does not require an extra delay line used for phase noise compensation. The generated OSSB radio frequency (RF) signal transmitted over single-mode fibers up to 20 km shows a flat electrical RF power response as a function of the fiber length. Read More

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September 2016

Down-conversion IM-DD RF photonic link utilizing MQW MZ modulator.

Opt Express 2016 Apr;24(8):8405-10

We present the first down-conversion intensity modulated-direct detection (IM-DD) RF photonic link that achieves frequency down-conversion using the nonlinear optical phase modulation inside a Mach-Zehnder (MZ) modulator. The nonlinear phase modulation is very sensitive and it can enable high RF-to-IF conversion efficiency. Furthermore, the link linearity is enhanced by canceling the nonlinear distortions from the nonlinear phase modulation and the MZ interferometer. Read More

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Experimental demonstration of deep frequency modulation interferometry.

Opt Express 2016 Jan;24(2):1676-84

Experiments for space and ground-based gravitational wave detectors often require a large dynamic range interferometric position readout of test masses with 1 pm/√Hz precision over long time scales. Heterodyne interferometer schemes that achieve such precisions are available, but they require complex optical set-ups, limiting their scalability for multiple channels. This article presents the first experimental results on deep frequency modulation interferometry, a new technique that combines sinusoidal laser frequency modulation in unequal arm length interferometers with a non-linear fit algorithm. Read More

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January 2016

Cascade photonic integrated circuit architecture for electro-optic in-phase quadrature/single sideband modulation or frequency conversion.

Opt Lett 2015 Nov;40(21):5038-41

A photonic integrated circuit architecture for implementing frequency upconversion is proposed. The circuit consists of a 1×2 splitter and 2×1 combiner interconnected by two stages of differentially driven phase modulators having 2×2 multimode interference coupler between the stages. A transfer matrix approach is used to model the operation of the architecture. Read More

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November 2015