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We propose and demonstrate a tunable microwave photonic (MWP) filter using a quantum dash mode-locked laser. By shaping the optical frequency comb spectrum, we can configure the MWP filter responses accordingly., 2021 IEEE Photonics Conference (IPC), October 18021, 2021, Vancouver, BC, Canada

We demonstrate broadband apodized phase-shifted waveguide Bragg gratings (PS-WBGs) in silicon-on-insulator. The PS-SWG WBG has a resonance with a bandwidth of 0.16 nm and corresponding Q-factor of ~10,000 within a stopband of~ 40 nm.

Theoretical uncertainties associated with the measurement of quantum bits have made Quantum Key Distribution (QKD) an attractive research topic for secure communication systems. Recent research in this area has focused on using weak coherent laser pulses as the carrier instead of the traditional approach of using single photon carriers. This opens the possibility to implement QKD infrastructure that is compatible with the existing optical fiber communication network. In this work, we report a theoretical study of a new approach that utilizes the Quantum Public Key Envelope (QPKE) based on the randomized Glauber states in a classical coherent optical communication system to obtain a secure communication. We verify the efficacy of the system using numerical simulation. We also study the possible approaches for an eavesdropper to test the degree of security enhancement of the proposed system at bitrate of 56 Gb/s. Two eavesdropping techniques are proposed for security analysis. A set of security parameters are used to simulate the variety of eavesdropping schemes.

We demonstrate second harmonic generation in a temperature-controlled MgO:PPLN crystal to obtain an output at 510 nm from a high-power polarization maintaining (PM) mode-locked fiber laser at 1020 nm with 35% conversion efficiency.

We realize an index-variable optical true time delay line based on an array of 40 subwavelength grating waveguides in silicon-on-insulator (SOI). Using the measured time delays, we simulate and demonstrate the application for antenna beamforming.

A multiband microwave photonic filter (MPF) based on optical spectral slicing is proposed. The optical spectral slicing is implemented by a programmable sampling function, and the tunability and reconfigurability of the multiband MPF are achieved in both simulations and experiments, which shows good agreement.

We demonstrate on-chip frequency comb generation using cascaded electro-optic Mach-Zehnder modulators in silicon photonics. Our on-chip frequency comb produces 9 lines with a frequency spacing of 6.67 GHz and an amplitude variation $\lt3$ dB.

We demonstrate a silicon microring modulator incorporating a compact multimode interference (MMI) as the coupling element. The resonance wavelength of the microcavity is controlled independently with two electrical signals, which can potentially be used as PAM-4 transmitters, directed logic gates, electro-optic switches, etc.

We introduce and experimentally demonstrate a reconfigurable microwave photonic filter based on temporal Talbot effects. An optical pulse source is employed to sample the microwave signal through intensity modulation. The sampled signal is then propagated through the Talbot-based microwave photonic filter, involving temporal phase modulation and chromatic dispersion. The microwave photonic filter exhibits a periodic transfer function whose passband frequency and frequency periodicity (free spectral range) can be programmed electrically by adjusting the phase-modulation profile, e.g., using an arbitrary waveform generator, without the need for manual adjustment of the optical components and with the potential for fast tuning of the filter’s response. The bandwidth of the filter passband can also be easily customized by adjusting the sampling pulse width using an optical bandpass filter.

We describe on-chip devices in silicon photonics for optical and microwave signal processing. We describe a mode selective nonlinear device, an integrated nonlinear optical loop mirror, a programmable comb filter, and a cascaded intensity modulator.

We demonstrate simultaneous interrogation of multiple fiber Bragg grating temperature sensors based on chirped microwave pulse generation using an arrayed waveguide grating Sagnac interferometer. Results show that the system provides a resolution of 16.3 ps/°C with an error of +/− 1 °C.

We demonstrate a thermally tunable optical filter based on periodic heating of a uniform Bragg grating structure on silicon-on-insulator. Five metal heater blocks are used to heat the grating to introduce multiple phase shifts and realize tunability of the reflection spectra.

We demonstrate a compact silicon photonic 4-channel optical add-drop wavelength multiplexer enabled by subwavelength-grating-based contra-directional couplers. Pass-bands of the device show on-chip insertion losses below 1.3 dB with wide 3 dB bandwidth of ∼ 6.7 nm suitable for coarse wavelength division multiplexing (CWDM) in short-reach optical interconnect applications.

We demonstrate alternate wavelength switching in a widely tunable, dual-wavelength Tm3+-doped fiber laser operating at 1900 nm. A comb filter based on a Sagnac loop incorporating a length of high-birefringence fiber is used to define the lasing wavelengths. By simple variation of a polarization controller within the laser cavity, alternate and sequential switching between single- and dual-wavelength output, as well as tunable operation over a range of 70 nm, is obtained.

We demonstrate simultaneous generating multiple microwave waveforms based on optical spectral shaping and wavelength-to-time mapping (WTM) technique. The spectral shaper is based on an arrayed waveguide Sagnac interferometer incorporating linearly chirped fiber Bragg gratings.

We demonstrate a multi-wavelength Brillouin Tm3+-doped fiber laser at 1873 nm in a linear cavity. Five order Brillouin wavelengths with channel spacing of ∼0.1 nm are obtained.

We review recent work on developing an integrated photonic device in silicon photonics for performing simultaneous multi-channel optical and microwave signal processing by exciting nonlinear optical effects in a mode-selective manner.

© 2009-2012 IEEE. We demonstrate RF arbitrary waveform generation based on microwave photonic filtering. We use four-wave mixing in a silicon nanowire to increase the number of taps in an N-tap microwave photonic filter (MPF). Using a programmable optical filter, we can control the tap weights and, hence, the MPF response and corresponding generated waveform. We show uniform and apodized waveforms with four taps and seven taps with tunable central frequencies.

Our previously proposed modulation format conversion from QPSK to BPSK was limited for a single polarization signal. In this report, we propose a novel conversion method from PDM-QPSK to PDM-BPSK with arbitrary azimuth angles.

We demonstrate integrated bandpass transmission filters based on incorporating uniform and chirped Bragg gratings in Sagnac loops in SOI. We use the latter as an optical spectral shaper to generate chirped microwave waveforms.

We demonstrate subwavelength grating filters in silicon-on-insulator based on Bragg gratings and racetrack resonators. The Bragg grating has a 3 dB bandwidth = 0.5 nm and reflectivity > 90%; the resonator has a 3 dB bandwidth = 1 nm and extinction ratio > 33 dB.

We demonstrate a novel integrated optical delay line approach based on silicon subwavelength gratings (SWGs). By 30% change in duty-cycle of SWG waveguides with a same length of 8mm to control their group index, up to ~30ps time-delay was achieved.

We demonstrate subwavelength grating devices in silicon-on-insulator including Bragg gratings, racetrack resonators, and optical delay lines. The Bragg grating filter has a 3 dB bandwidth of 0.5 nm and a reflectivity of 90%; the racetrack resonator has a 3 dB bandwidth of 1 nm, a free spectral range of 4.6 nm, and an extinction ratio as high as 33 dB; the optical delay lines achieve ~30ps time-delay with 30% change in duty-cycle.

© 2014 IEEE. We demonstrate bandpass transmission filters and optical add-drop multiplexers on SOI based on interferometric structures incorporating a pair of sidewall Bragg gratings.

We propose using an optical fiber cable to monitor distributed vibration changes. The cable connects a vibration point sensor based on a twin fiber Bragg grating (FBG) interferometer operating in reflection to its interrogation unit that locks a narrowband DFB laser to the central interference fringe.

—We propose and demonstrate photonic arbitrary waveform generation based on microwave photonic filtering. We show uniform and apodized waveforms, as well as tuning of the RF spectrum. We discuss how the photonic structure can be fully integrated in silicon photonics. Keywords—Microwave photonics, arbitrary waveform generation, silicon photonics I. I NTRODUCTION The development of photonic approaches for RF arbitrary waveform generation (RF-AWG) are of interest due to advantages of being tunable, reconfigurable, and compatible with fiber optic transmission [1]. Indeed, a number of photonic structures and techniques for RF-AWG have been demonstrated, including those based on nonlinear optical effects in fiber or semiconductor optical amplifiers, optical frequency comb generation, phase modulation-to-intensity modulation using discrimination filters, and microwave photonic filtering [2-6]. The field of microwave photonic filters (MPFs) is extremely rich and the design of MPFs with reconfiguration and/or tuning capabilities has been the subject of intense research. Many structures have been proposed and important results have been demonstrated [6]. MPFs employ typically discrete components resulting in bulky, benchtop implementations. To address issues related to compactness, stability, power consumption, and ultimately mass production for reduced cost, the development of integrated (single chip) MPFs will be significant. There have been several integrated MPFs and MPF systems reported in chalcogenide and silicon (including silicon nitride) [7-10]. Those based in silicon are especially attractive for their compatibility with CMOS processing. In this paper, we demonstrate RF-AWG based on microwave photonic filtering. We also discuss the integration of the various building blocks and the possibility for a fully photonic integrated circuit (PIC) equivalent. II. G

We demonstrate an integrated SPM-based 2R optical regenerator in SOI comprising a silicon nanowire and a step-chirped sidewall Bragg grating.

We demonstrate the all-optical reconfigurable time slot interchange (TSI) of in- dividual bits at 40 Gb/s based on four-wave mixing (FWM) and a programmable planar lightwave circuit (PLC). The PLC is used to generate different control signals (masks) that determine which bits undergo TSI. By programming the PLC to generate two differ- ent masks, two different TSI patterns are obtained. TSI is achieved using FWM between the data signal and the desired mask with bidirectional propagation in a length of highly nonlinear fiber. Error-free operation is obtained for both of the TSI patterns, with a power penalty G 5.2 dB, at a bit error rate of 10 � 9 .

We demonstrate a dual-band Tm3+:ZBLAN fiber laser emitting simultaneously at 810 nm and 1487 nm through two transitions originating from the 3H4 energy level. Upconversion pumping at 1064 nm is used.

26th IEEE Photonics Conference (IPC) -- SEP 08-12, 2013 -- Bellevue, WA, WOS: 000369918000203, We compare using nonlinear fiber to a silicon nanophotonic waveguide in implementing a reconfigurable microwave photonic filter. Additional taps are generated via four wave mixing and tap levels are controlled by a programmable filter., IEEE, Amer Chem Soc, Multidisciplinary Digital Publishing Inst, IEEE Cloud Comp, LioniX

We demonstrate error-free wavelength conversion of 16-QAM 28-GBaud (112 Gb/s) signals and 1-to-6 wavelength multicasting of 16-QAM 22-GBaud (6×88 Gb/s) signals based on four wave mixing in a dispersion engineered silicon nanowire.