Microring Resonator System Research Articles

Multiband dual polarized OFDM signal: Generation and distribution over fiber

Microring Resonator (MRR) system is utilized to generate comb signal including eight carriers, owing 10GHz free spectral range (FSR) to be applied in wavelength-division multiplexing (WDM) systems. Applying multiband (MB) approach, the ultra-high spectral effective orthogonal frequency-division multiplexing (OFDM) technology is utilized to modulate each of the simulated multicarrier and by taking advantage of the dual polarization (DP) technique the high data rate of 236.8Gb/s MB-DP-OFDM signal is achieved. The MB-DP-OFDM signal is transmitted through 50km single mode fiber (SMF) and received by the coherent receiver. The system’s performance was assessed by using the bit error rate (BER) of the system, where the BER of 2×10−3 was achieved.

InGaAsP/InP Microring Resonator (MRR) Waveguide Used to Generate Soliton Comb with Tunable Channel Spacing

A novel system of tunable channel spacing soliton comb generation is presented using a PANDA ring resonator incorporated with an add-drop filter system. The intense optical fields known as soliton comb can be generated. Results show that soliton comb can be generated with un-equal spaced or variable free spectral range (FSR) by using the input bright soliton pulse into the microring resonator (MRR) system. The proposed comb filter exhibits a large tuning range in channel spacing. Our simulations shows that the channel spacing can be continuously tuned form up to 10 GHz, where the centre wavelength of the input power has been selected at 50 GHz. The structure of the proposed MRR's waveguide (InGaAsP/InP) and mode propagation profile have been presented in this research.

Transmission performances of solitons in optical wired link

Chaotic signal generation from microring resonators (MRRs) is presented. Two 1.5μm Gaussians with spectral profile having powers of 600mW are input into the system of MRRs. Using nonlinear conditions, the chaotic signals can be generated and propagated within the ring medium. Results show that the chaotic signals can be controlled and manipulated by using additional Gaussian input into the add port of the MRRs. A balance should be achieved between dispersion and nonlinear lengths when the propagating pulse is soliton. Chaotic output signals from the ring resonator can be converted to logic codes then inserted into an optical fiber transmission link which has a length of 180km in order to perform the transmission performance. The transmitted signals in the form of spatial and temporal solitons can be detected at the end of the transmission link.

Multiwavelength generation using an add-drop microring resonator integrated with an InGaAsP/InP sampled grating distributed feedback

A system of an add-drop microring resonator integrated with a sampled grating distributed feedback (SG-DFB) is investigated via modeling and simulation with the time-domain traveling wave (TDTW) method. The proposed microring resonator comprises a SiO2 waveguide integrated with an InGaAsP/InP SG-DFB, and the SiO2 waveguide consists of a silicon core having a refractive index of 3.48 and Kerr coefficient of 4.5 × 10-18 m2/W. The SG-DFB consists of a series of grating bursts that are constructed using a periodic apodization function with a burst spacing in the grating of 45 μm, a burst length of 5 μm, and 10 bursts across the total length of the SG-DBR. Transmission results of the through and drop port of the microring resonator show the significant capacity enhancement of the generated center wavelengths. The Q-factor of the microring resonator system, defined as the center wavelength (λ0) divided by 3 dB FWHM, without and with integration with the SG-DFB is calculated as 1.93 × 105 and 2.87 × 105, respectively. Analysis of the dispersion of the system reveals that increasing the wavelength results in a decrease of the dispersion. The higher capacity and efficiency are the advantages of integrating the microring resonator and the InGaAsP/InP SG-DFB.

2 × 2 MIMO-OFDM-RoF generation and transmission of double V-Band signals using a microring resonator system

Multi-input multi-output (MIMO) signals have been all-optically generated via orthogonal frequency division multiplexing, and transmitted over a 50 km single mode fibre (SMF) optical link and also a 5 m 2 × 2 MIMO wireless link. The series of constituent single and multi-carrier optical soliton pulses, at frequencies of f1 = 192.6988, f2 = 192.7588, f3 = 192.79 and f4 = 192.84 THz that are applicable for radio over fibre (RoF) systems, were created using a microring resonator system. Sixty four multi-carriers with specific free spectral range of 109.37 MHz across a selected range of 192.7553–192.7623 THz were produced for the purpose of establishing two MIMO V-Band RF signals, and single carriers operating at f3 and f4 optically transported two separate MIMO signals over an RoF link. The optical single sideband with carrier modulation technique has been implemented so as to overcome RF power degradation. The resultant bit error rate (BER) calculation of overall system performance is discussed, and power penalties of 1.7 and 4.7 dB in 25 and 50 km SMF transmissions at the BER threshold respectively have been identified. The results of this research show that transmission of MIMO signals is feasible for up to a 50 km SMF path length and wireless distance of 3 m.

Rabi oscillation generation in the microring resonator system with double-series ring resonators

In this paper, a microring resonator (MRR) system using double-series ring resonators is proposed to generate and investigate the Rabi oscillations. The system is made up of silicon-on-insulator and attached to bus waveguide which is used as propagation and oscillation medium. The scattering matrix method is employed to determine the output signal intensity which acts as the input source between two-level Rabi oscillation states, where the increase of Rabi oscillation frequency with time is obtained at the resonant state. The population probability of the excited state is higher and unstable at the optical resonant state due to the nonlinear spontaneous emission process. The enhanced spontaneous emission can be managed by the atom (photon) excitation, which can be useful for atomic related sensors and single-photon source applications.

Solitonic Pulse Generation for Optical Wireless Communication Using Microring Resonator

In this paper, a system of microring resonator (MRR) is presented to generate picosecond solitonic pulse for optical wireless communication. When a Gaussian pulse is circulated inside the first ring in the proposed system, chaotic signals are generated because of the nonlinear Kerr effect. Then next MRR in the system filters the chaotic signals and the solitonic pulse shape is generated. Then an add/drop filter is used to tune soliton pulses where the accurate FWHM of 130 ps and FSR of 3.7 ns with power of 2.45 W will be filtered. The performance of the proposed solitonic pulse shape is analysed in terms of bit error rate (BER). During the analysis, the proposed pulse shape is compared against the conventional rectangular and Gaussian pulse shapes in an optical wireless communication system (OWC) with an additive white Gaussian noise (AWGN) channel. Results show the superiority of the proposed solitonic pulse shape for OWC.

Radio Frequency Signal Generation and Wireless Transmission Using PANDA and Add/Drop Systems

The radio frequency (RF) signal generation and its modulation is the basic building block of wireless communication system. High frequency RF signals are desired in high speed systems but traditional methods to generate high frequency RF signals suffered from electronic devices data processing rate. On the other hand, spectral efficient modulation is also played vital rule in the high speed wireless communication where orthogonal frequency-division multiplexing (OFDM) transmission is mostly preferred. Due to the challenges regarding to electronic devices, optically generation and processing of RF OFDM signals has gained considerable attention. In this work microring resonator (MRR) system is used to implement all optically generation and modulation of RF OFDM signal. The MRRs can be used as filter devices where generation of high frequency (GHz) soliton signals as single and multi-carrier can be performed using suitable system parameters. The results show the generation of 64 multi-carriers evenly spaced in the range from 54.09 GHz to 55.01 GHz to generate OFDM signal all optically, where the RF modulation was achieved by two optical carriers with free spectral range (FSR) = by 5 GHz.

Increment of Access Points in Integrated System of Wavelength Division Multiplexed Passive Optical Network Radio over Fiber.

This paper describes a novel technique to increase the numbers of access points (APs) in a wavelength division multiplexed-passive optical network (WDM-PON) integrated in a 100 GHz radio-over-fiber (RoF). Eight multi-carriers separated by 25 GHz intervals were generated in the range of 193.025 to 193.200 THz using a microring resonator (MRR) system incorporating an add-drop filter system. All optically generated multi-carriers were utilized in an integrated system of WDM-PON-RoF for transmission of four 43.6 Gb/sec orthogonal frequency division multiplexing (OFDM) signals. Results showed that an acceptable BER variation for different path lengths up to 25 km was achievable for all four access points and thus the transmission of four OFDM channels is feasible for a 25 km standard single mode fiber (SSMF) path length.

Analytical and simulation results of micro-ring resonator system using two eyes imaging model

In this review article, the artificial vision model using the 3 cascaded conjugate mirrors system can be constructed, analyzed and simulated. A single 3D pixel (point) imaging construction is formed and obtained by using the conjugate mirror concept, where the large area of pixels can be potentially constructed and realized for large area application. This is a simulation work, where the software program is the finite difference time domain (FDTD) commercial program (Opti-wave). However, the used device parameters and materials can be fabricated and formed the artificial eyes for 3D artificial vision. Simulation result obtained has shown that the whispering gallery modes (WGMs) of radiation within the cascaded microring conjugate mirrors can be easily formed, and are coupled by the two nonlinear side rings, which can be potentially used for 3D imaging pixel construction applications by the two eyes construction model.

Cold laser therapy modeling of human cell/tissue by soliton tweezers

The interferometer system of microring resonator (MRR) can be used to generate soliton tweezers applied for medical applications. This system uses the nonlinear behaviors of light pulse traveling within a fiber optics MRR. The soliton tweezers can be used to contact the biological cells of a human tissue. Here, the non-heat creating laser is required to perform the cold laser (CL) therapy which can be utilized by a generation of low power soliton tweezers using the MRRs. The NIR (near infra-red) laser is used to generate soliton tweezers which are able to penetrate profoundly into tissues in order to improve injury healing and tissue regeneration. The Dark solitons and Gaussian beam with central wavelength of 800nm collide within the MRR system lead to generate ultra-short soliton tweezers. This type of treatment is effective and based on the photochemical and photobiological effects of the cells and tissues or any biological response by means of power transfer. Thus, the CL using the soliton tweezers provides energy toward the entire body in the form of non-thermal photons of light. In this research soliton tweezers with full width at half maximum (FWHM) of 1.5, 4, 6.8 and 15nm are generated and used to interact with the living cells and human tissues.

Analysis of ripple noise in resonant spectrum of SOI micro-ring resonator

Micro-ring resonator has been attracting attentions in studies of filters, modulators, lasers, sensors and other fields owing to the characteristics of highly integrated, low power consumption and high sensitivity. The transmission characteristics of micro-ring resonator directly determine the performance of micro-optical device for its key component of various integrated optical devices. The causes of and influences on resonant spectrum of ripple noise were analyzed by the combination of micro-ring resonator theory and Fabry-Perot Interferometer (FPI). Coupling experiments were designed to obtain and analyze the free spectrum range (FSR) and amplitude of ripple noise. The experimental results show that coupling gratings are the cause of ripple noise, which is well consistent with theoretical analysis. The relationship between etching depth of coupling gratings and ripple amplitude was found and analyzed. The study provides a reference for further optimization of micro-ring resonator and error analysis of micro-ring resonator system.

A Review of Ultra-Short Soliton Pulse Generation Using InGaAsP/InP Microring Resonator (MRR) Systems

System of microring resonators (MRRs) incorporating with an add/drop MRR system are presented to generate single and multi-temporal and spatial ultra-short soliton pulses applicable in optical soliton communications. The chaotic signals caused by the nonlinear condition could be generated and propagated within the system. The Kerr effect in the MRR system induces the nonlinearity condition. The proposed MRR systems are used to generate ultra-short soliton pulse within the system. Using the appropriate MRR parameters, ultra-short spatial and temporal signals are generated spreading over the spectrum. In this work, narrow soliton pulses could be localized within the proposed systems. Here soliton pulses of 0.7 ps, 0.83 fs and 19 pm are generated using series of MRRs connected to an add/drop MRR system. The nonlinear refractive index is n2=2.2 x 10-17 m2/W. Using the panda ring resonator system, the ultra-short soliton pulses with full width at half maximum (FWHM) and free spectral range (FSR) of 5 MHz and 2 GHz, were generated at the throughput port. The output signals pulses with FWHM of 10 MHz and FSR of 2 GHz could be obtained at the drop port of the system. As second results using this system, multi-carrier soliton pulses with FWHM=20 MHz are localized within this system with respect to 20,000 roundtrips of the input pulse. Localized optical tweezers could be generated using the half-Panda MRR system, where the peaks have FWHM and FSR of 8.9 nm and 50 nm respectively. The nonlinear refractive index was selected to n2=2.5×10-17 m2/W.

Full Width at Half Maximum (FWHM) Analysis of Solitonic Pulse Applicable in Optical Network Communication

In this paper, we propose a system of microring resonator (MRR). This system uses a laser diode input which can be incorporated with an optical add/drop filter system. When light from the laser diode feedbacks to the fiber ring resonator, the pulses in the form of soliton can be generated by using appropriate fiber ring resonator parameters and also the input power. The filtering process occurs during the propagation of the pulse within the ring resonators. The full width at half maximum (FWHM) or bandwidth characterization of the pulse can be performed using the proposed system. Results obtained have established particular possibilities from the application such as optical network communication. The obtained results show the effects of coupling coefficients and ring radius on the bandwidth of the soliton pulse, where the graph of the FWHM versus the variable parameters such as the radius and coupling coefficient are presented.

All-Optical Generation of Two IEEE802.11n Signals for 2 <inline-formula> <tex-math notation="TeX">$\times$</tex-math></inline-formula> 2 MIMO-RoF via MRR System

A radio-over-fiber system capable of very spectrally efficient data transmission and based on multiple-input multiple-output (MIMO) and orthogonal frequency-division multiplexing (OFDM) is presented here. Carrier generation is the basic building block for implementation of OFDM transmission, and multicarriers can be generated using the microring resonator (MRR) system. A series of MRRs incorporated with an add/drop filter system was utilized to generate multicarriers in the 193.00999–193.01001-THz range, which were used to all-optically generate two MIMO wireless local area network radio frequency (RF) signals suitable for the IEEE802.11n standard communication systems, and single wavelengths at frequencies of 193.08, 193.1, and 193.12 THz with free spectral range of 20 GHz used to optically transport the separated MIMO signals over a single-mode fiber (SMF). The error vector magnitude (EVM) and bit error rate of the overall system performance are discussed. Results show that the generated RF signals wirelessly propagated through the MIMO channel using the 2 $\times$ 2 MIMO Tx antennas. There is an acceptable EVM variation for wireless distance lower than 70, 30, and 15 m. It can be concluded that the transmission of both MIMO RF signals is feasible for up to a 50-km SMF path length and a wireless distance of 15 m.

Generation and transmission of 3 × 3 W-Band multi-input multi-output orthogonal frequency division multiplexing-radio-over-fiber signals using micro-ring resonators.

Using the micro-ring resonator (MRR) system, the single and multi-carriers at frequencies of f(1)=192.898, f(2)=192.990, f(3)=193.1, f(4)=193.315, and f(5)=193.537 THz with a free spectral range (FSR) of 92, 110, 215, and 222 GHz, respectively, are generated to be suitable for a radio-over-fiber (RoF) system based on multi-input multi-output (MIMO) with orthogonal frequency division multiplexing (OFDM). Demonstrated are the concepts of all-optical MIMO signal generation and its transmission over a 50 km single mode fiber (SMF) optical link and an up to 3 m wireless link. Sixty-four multi-carriers are used in the all-optical generation of three MIMO W-Band RF signals, where the single carriers (f(3)-f(5)) transport the signals over the RoF link. The bit error rate (BER) of the overall system performance is discussed; thus, the transmission of MIMO signals is feasible for up to an SMF path 50 km long and a wireless distance of 3 m.

Optical Quantum Generation and Transmission of 57–61 GHz Frequency Band Using an Optical Fiber Optics

An optical panda ring resonator connecting to two microring resonators (MRRs) can be used to generate a high frequency optical soliton. The optical soliton pulse of 57-61 GHz can be generated and transmitted via an optical quantum transmission link. This system uses a Gaussian laser pulse propagating within a nonlinear MRRs system. The ultra-short single and multi soliton pulses within the range of 57-61 GHz can be generated and seen at the through and drop ports of the system. The transmission link consists of MRRs system, optical transmitter, connector, fiber optics, erbium doped fiber amplifier (EDFA), receiver and antenna which provide transmission of optical soliton via the wired/wireless communications. The fiber optic has a length of 1 km, where the wireless link covers a short distance optical communication of 10 m. Here, the transmitted optical soliton pulses can be received, detected and used by the users.

Detection of Salmonella bacterium in drinking water using microring resonator

A new microring resonator system is proposed for the detection of the Salmonella bacterium in drinking water, which is made up of SiO2-TiO2 waveguide embedded inside thin film layer of the flagellin. The change in refractive index due to the binding of the Salmonella bacterium with flagellin layer causes a shift in the output signal wavelength and the variation in through and drop port's intensities, which leads to the detection of Salmonella bacterium in drinking water. The sensitivity of proposed sensor for detecting of Salmonella bacterium in water solution is 149 nm/RIU and the limit of detection is 7 × 10− 4 RIU.

Femtosecond Optical Quantum Memory Generation Using Optical Bright Soliton

Optical system of microring resonator is presented to form the femtosecond (fs) memory time of optical soliton signals. Localised soliton pulses can be stored within the microring device using suitable parameters of the system. The optical quantum memory is a solution for storing large amounts of data which is very inexpensive and more importantly, it helps to transport the data between optical communication devices. The integrated optical system of a series of microring resonators and two add or drop systems are presented. This system is used to generate chaotic signals using an input bright soliton pulse. The large output gain is obtained by the self-phase modulation which is required to balance the dispersion effects of the medium. The ultra-short single and multi-spatial and temporal soliton pulses are obtained by using the add/drop filter systems. The results show that the single and multi-soliton pulses can be localised within the microring waveguide while the optical quantum memory time of 83 fs could be generated.

Optical Stretcher of Biological Cells Using Sub-Nanometer Optical Tweezers Generated by an Add/Drop Microring Resonator System

The design system consists of a nonlinear modified add/drop Microring Resonators (MRR) to build up optical tweezers in the form of potential wells is presented. The optical tweezers can be used for sub-nanometer objects trapping to form an optical stretcher used to deform the biological cells. The fabricated material used is InGaAsP/InP, which provide the required output signals. The optical tweezers can be formed by the dark soliton pulses and can be tuned and amplified using the Gaussian laser beam input. The optical dark soliton pulses with the central wavelengths range 1.4 to 1.55-m are fed into the system, collide with the input Gaussian laser beam at the add port and finally the optical tweezers with bandwidth of 4, 12 and 18 nm could be generated and used to trap sub-nanometer objects using a molecular buffer system. Interacting the tweezers holding the subnanometer objects with human tissue, influence the cellular surface of the cells by the generated forces. Therefore an optical stretcher can be formed to deform the biological cells of human tissue using optical tweezers.