yu yu

• University of Reading

We propose and fabricate an on-chip mode division multiplexed (MDM) photonic interconnection system. Such a monolithically photonic integrated circuit (PIC) is composed of a grating coupler, two micro-ring modulators, mode multiplexer/demultiplexer, and two germanium photodetectors. The signals’ generation, multiplexing, transmission, demultiplexin...

An on-chip polarization insensitive interconnection is proposed and fabricated based on SOI platform. The proposed circuit is experimentally demonstrated in fiber-optic communication system utilizing wavelength, polarization and mode multiplexing techniques with power penalty of 3.2dB.

We demonstrate an integrated largest time-bandwidth product (TBP) microwave photonic Hilbert transformer, using synthesized Bragg grating design and fabrication techniques. Devices operate from 50 GHz to 2.5 THz, with the TBP approaching 50.

We demonstrate an on-chip WDM-compatible mode multiplexing system with function of phase demodulation. The proposed scheme can be useful at the interface of long-haul and onchip communication systems, which prefer phase and intensity modulated formats respectively.

We propose and fabricate a novel four-port polarization diversity coupler for vertical coupling. With the help of 45° reflectors and improved 2x1 couplers, an ultralow coupling loss of -4.8dB is experimentally measured with polarization insensitivity.

We propose and experimentally demonstrate a novel scheme which can simultaneously realize wavelength-preserving and phase-preserving amplitude noise compression of a 40 Gb/s distorted non-return-to-zero differential-phase-shift keying (NRZ-DPSK) signal. In the scheme, two semiconductor optical amplifiers (SOAs) are exploited. The first one (SOA1) i...

The phase regeneration for the mode-division multiplexing (MDM) differential phase shift keying (DPSK) signals in a single multimode silicon waveguide, is proposed and successfully demonstrated in the simulation. The regeneration is based on the mode-selective phase sensitive amplification (PSA). When the pumps and the signal are carried on the sam...

We propose and experimentally demonstrate all-optical NRZ-DPSK to RZ-OOK modulation format conversion for wavelength multicasting based on a single SOA. Using T-XPM effect in SOAs, a-1.38dB power penalty at BER of 10-9 can be achieved.

A polarization rotator that converts the input TE1 mode to TM1 mode is proposed and demonstrated theoretically. The conversion efficiency is higher than 90% over the C-band, with excess loss as low as 0.35dB.

A compact silicon-on-insulator device used for conversions between polarization division multiplexing (PDM) and mode division multiplexing (MDM) signals is proposed and experimentally demonstrated by utilizing a structure combining the improved two-dimensional grating coupler and two-mode multiplexer. The detailed design of the proposed device is p...

An all-optical clock recovery (CR) scheme with wide locking range is demonstrated, based on a silicon microring resonator (MRR) and a semiconductor optical amplifier (SOA). The MRR with a free spectral range of 40 GHz works as a comb filter, which removes the modulation information, whereas the SOA operating in the saturation regime performs amplit...

We propose and fabricate a novel circuit that combines two two-dimensional (2D) grating couplers and a microring resonator (MRR). According to the polarization states, one 2D grating coupler first splits the input signals into two orthogonal paths, which co-propagate in the loop and share a common MRR, and then the two paths are combined together b...

We propose and experimentally demonstrate a feasible integrated scheme to solve all-optical differential equations using microring resonators (MRRs) that is capable of solving first- and second-order linear ordinary differential equations with different constant coefficients. Employing two cascaded MRRs with different radii, an excellent agreement...

We propose and fabricate a scheme that combines a two-dimensional (2D) grating coupler and a delay interferometer (DI) in a loop configuration. According to the polarization states, the 2D grating coupler first splits the input signals into two paths, which copropagate in the loop and share a common DI, and then combines the two paths together to t...

We propose and experimentally demonstrate amplitude regeneration for non-return-to-zero differential-phase-shift-keying (NRZ-DPSK) signal at 40 Gb/s with two cascaded semiconductor optical amplifiers (SOAs) and a subsequent delay interferometer (DI). The amplitude regeneration can reduce the accumulation of nonlinear phase noise (NPN), which is one...

We propose and demonstrate all-optical amplitude regeneration for the wavelength division multiplexing and polarization division multiplexing (WDM-PDM) return-to-zero phase shift keying (RZ-PSK) signals using a single semiconductor optical amplifier (SOA) and subsequent filtering. The regeneration is based on the cross phase modulation (XPM) effect...

We proposed and demonstrated an all-optical format conversion from return-to-zero quadrature phase shift keying (RZ-QPSK) to non-return-to-zero QPSK (NRZ-QPSK) at 40 Gb/s using a half bit delay interferometer (DI). Due to the constructive interference in the DI, the format conversion was achieved with the phase information preserved. Q penalty for...

A simple scheme to generate optical quadrature amplitude modulation (QAM) signals is proposed based on different types of delay interferometers (DIs). The simulated results show that 16QAM, 64QAM and 256 QAM optical signals can be generated by 2×2, 3×3 and 4×4 DI, respectively, and the outputs of the proposed scheme are similar to those of the conv...

High-speed all-optical logic circuits have attracted much attention because of their important roles in signal processing in next-generation optical networks. The digital encoder is widely used in binary calculation, multiplexing, demultiplexing, address recognition and data encryption. A priority encoder allows the existence of multiple valid inpu...

We demonstrate parallel amplitude regeneration for 6*40Gb/s RZ-DPSK signals using the XPM effect in a single saturated SOA and subsequent narrow filtering. An average -1.3 dB power penalty can be achieved for all the channels.

We demonstrate multi-channel non-return-to-zero (NRZ) to return-to-zero (RZ) conversions with tunable output pulse-width and single-to-dual function, using a phase modulator and an array waveguide grating (AWG), which acts both detuned multi-channel filter and demultiplexer. Four-channel NRZ signals after transmission can be converted to eight-chan...

We demonstrated experimentally 40 Gbit/s all-optical format conversions between return-to-zero (RZ) and nonreturn-to-zero (NRZ) using a fiber delay interferometer (FDI) and a single semiconductor optical amplifier (SOA). Firstly, 40 Gbit/s data format conversion from RZ to NRZ is realized using a FDI with temperature control and an optical bandpass...

We propose and simulate a simple scheme of all-optical format conversion from non-return-to-zero differential phase-shift keying (NRZ-DPSK) to return-tozero differential phase-shift keying (RZ-DPSK) by using phase modulators and detuning filters. The operation principle is theoretically analyzed and simulated by exploiting spectra, temporal wavefor...

We propose and demonstrate multi-channel parallel format conversions from the non return-to-zero differential phase shift keying (NRZ-DPSK) to the return-to-zero DPSK (RZ-DPSK) using a single semiconductor optical amplifier (SOA). The simultaneous conversions are based on the cross phase modulation (XPM) effect, which is induced by a synchronous op...

In this paper, we present an optimized quantum-well (QW)-semiconductor optical amplifier (SOA) which is capable of regenerating phase-modulated signals, such as return-to-zero differential-phase-shift keying (RZ-DPSK) signal. Based on the optimized QW SOA, the amplitude fluctuations are suppressed while the phase information is preserved. The essen...

We proposed and demonstrate an all-optical demodulation and format conversion scheme for multi-channel (carrier suppressed) return-to-zero differential phase shift keying ((CS)RZ-DPSK) signals. By utilizing a single delay interferometer (DI) with half bit delay, multi-channel (CS)RZ-DPSK signals can be demodulated simultaneously at the destructive...

We demonstrate multi-channel regenerative non-return-to-zero (NRZ) to return-to-zero (RZ) conversions with tunable output pulse-width and single-to-dual function, using a phase modulator and an array waveguide grating (AWG). Transmission and bit error ratio (BER) show a good performance for the converted RZ signal compared with conventional one.

A code-label recognition time of less than 500ps is demonstrated using low-cost FIR-filters. The electronically-processed label provides a control signal from an auto-correlated label. Error-free electronic code-label switching of an optical 10Gb/s signal is demonstrated.

We propose and demonstrate a simple and flexible approach to generate vestigial side band modified duobinary return-to-zero (VSB MD-RZ) signals at 10–40Gb/s, using a dual-drive Mach–Zehnder modulator and a detuned optical band-pass filter. The performance of the proposed VSB MD-RZ signal is investigated by comparing with double side band MD-RZ (DSB...

All-optical signal processing functions are key enabling technologies for signal regeneration and switching in next generation optical networks. SOA has been receiving much attention in all-optical signal processing for its various nonlinear effects and potential to be integrated, and it has been exploited to realize all-kinds of signal processing...

We demonstrate a multi-wavelength semiconductor optical amplifier (SOA) fiber ring laser with a dual-pass Mach–Zehnder interferometer (MZI) filter. Two SOAs with different gain spectra provide sufficient gain and a wider gain spectrum to facilitate multi-wavelength lasing. The dual-pass MZI, configured by adding an optical isolator to the two outpu...

We propose and demonstrate a multi-level all-optical format conversion from NRZ signal to RZ signal, using a semiconductor optical amplifier (SOA) and a detuned optical filter. The three-level NRZ signal and a synchronous optical clock signal are injected into an SOA, which acts as a nonlinear element and causes the spectrum of the input NRZ signal...

We propose and demonstrate a simple and flexible all-optical NRZ-DQPSK receiver based on optical detuned filtering. The proposed demodulator is quite flexible to input bit rates, which means it can be used for different bit rates without any change. With two given optical band-pass filters, simulation and comparison show that NRZ-DQPSK signals at 2...

We propose and demonstrate a simple and flexible all-optical NRZ-DQPSK receiver based on optical detuned filtering. By adjusting the detuning of two given filters, the in-phase and quadrature data can be demodulated from 20-to-80Gb/s NRZ-DQPSK signals.

We experimentally demonstrate an all-optical clock recovery scheme for the return-to-zero data with single- and multiwavelength. This scheme is mainly based on clock-like pulse generation from an active filter with a multiquantum-well Fabry-Perot semiconductor optical amplifier and amplitude-equalization with self-nonlinear polarization switching....

A novel and simple non-return-to-zero differential phase shift keying (NRZ-DPSK) wavelength division multiplexing (WDM) system, which can simultaneously demultiplex and demodulate multiple wavelengths, is proposed and investigated in this paper. The phase-to-intensity demodulation principle is based on detuned filtering, which is achieved by using...

All-optical clock recovery (CR) from 20 Gbit/s nonreturn-to-zero differential phase-shift-keying (NRZ-DPSK) signals are demonstrated experimentally by using a polarization-maintaining fiber loop mirror filter (PMF-LMF) and a semiconductor optical amplifier (SOA) fiber ring laser. Only by adjusting polarization controller (PC), NRZ-DPSK signals were...

Photonic generation of ultrawideband (UWB) monocycle and doublet pulses is experimentally demonstrated using a cascaded electroabsorption modulator (EAM) and semiconductor optical amplifier by exploiting a combination of cross-absorption modulation and cross-gain modulation. The polarities and shapes of UWB monocycle and doublet pulses can be simpl...

We propose and demonstrate simultaneous optoelectronic NRZ-to-RZ format conversion for multiple DWDM channels with some regenerative properties, using a single phase modulator (PM) and a fibre delay-interferometer (DI). In order to accommodate multiple DWDM channels, the DI is designed to have a free spectral range (FSR) equal to the channel spacin...

Nonlinear patterning (NLP) effect in wavelength conversion based on transient cross-phase modulation (XPM) in semiconductor optical amplifier (SOA) assisted with a detuning filter is theoretically investigated. A non-adiabatic model is used to estimate the ultrafast dynamics of gain, phase and electron temperature in the SOA. Simulation results sho...

We propose a novel and simple non-return-to-zero differential phase shift keying (NRZ-DPSK) wavelength division multiplexing (WDM) system which can simultaneously demultiplex and demodulate multiple wavelengths. The phase-to-intensity demodulation principle is based on detuned filtering, which is achieved by using a single commercial array waveguid...

We demonstrate a fiber ring laser with a dispersion compensation fiber (DCF) and a delayed interferometer (DI) with temperature control, which is able to switch eleven wavelengths one by one. In ring cavity, DCF supplies different effective cavity lengths for different wavelengths, DI generates a wavelength comb corresponding to the ITU grid, a fla...

We demonstrate simultaneous NRZ-to-RZ conversion for 16 DWDM channels, using a single SOA and a subsequent delay interferometer (DI) acting as a comb-like filter to control the obtained pulse-width for all of the channels. The SOA is operated in deep saturation, resulting in weak cross gain modulation and cross phase modulation induced crosstalk be...

We propose and demonstrate all-optical clock recovery (CR) from nonreturn-to-zero differential phase-shift-keying (NRZ-DPSK) signals at different bit rates theoretically and experimentally. By pre-processing with a single optical filter, clock component can be enhanced significantly and thus clock signal can be extracted from the preprocessed signa...

We demonstrate a simple configuration for clock recovery from a nonreturn-to-zero signal, which is preprocessed by a narrowband filter. Evidently, the clock component is enhanced after the filter. Compared with previous preprocessing schemes, the single filter is simple and suitable for different bit rates. The output performances related to the ba...

An all-fiber delay interferometer and narrowband filter based an all-optical format conversion scheme, which can convert return-to-zero (RZ) signals with variable duty cycles to nonreturn-to-zero signals, is proposed and demonstrated. The passive converter is independent of wavelength and input power. The operation principle is analyzed and simulat...

40Gbit/s all-optical format conversion from the carrier-suppressed return-to-zero (CS-RZ) to the non-return-to-zero (NRZ) is proposed and demonstrated with a temperature-controlled all-fiber delay interferometer (DI) and narrow-band filters. The NRZ signals can be achieved at two different wavelengths simultaneously from the original CS-RZ, with po...

All-optical format conversion from return-to-zero (RZ) to non-return-to-zero (NRZ) is demonstrated with temperature-controlled all-fibre delay interferometer (DI) at 20 Gb/s. The operation principle is theoretical analysed with the help of numerical simulation and spectra analysis. Theoretical analysis results are consistent well with the experimen...

20 Gb/s all-optical format conversion from return-to-zero (RZ) to non-return-to-zero (NRZ) is demonstrated with temperature-controlled all-fiber delay interferometer (DI). The operation principle is theoretical analyzed with the help of numerical simulation and spectra analysis. Theoretical analysis results are well coincidence with experimental re...

A complete analytical model of the polarization characteristics of a semiconductor laser amplifier in a loop mirror (SLALOM) is presented. Based on this model, various kinds of output for all-optical conversion of non-return-to-zero (NRZ) to pseudo-return-to-zero (PRZ) signals, based on a simple SLALOM scheme, are analyzed theoretically. Simulation...

All-optical clock recovery (CR) from 20-Gb/s nonreturn-to-zero differential phase-shift-keying (NRZ-DPSK) signal is demonstrated, with an all-fiber delay interferometer (DI) and a mode-locked semiconductor optical amplifier (SOA) fiber laser. The tunable DI serves as an all-optical DPSK demodulator and the phase-modulated NRZ-DPSK signal is convert...