Nonlinear Microring Resonator Research Articles

Design and Analysis of Ultralow Voltage Graphene on the Silicon Rich Nitride Tunable Ring Resonator-Based Add-Drop Filter for DWDM Systems

We propose and simulate a third-order 3D electro-optically highly tunable compact add-drop filter based on nonlinear microring resonators. The used tuning mechanism relies on enhanced Kerr nonlinearity in a graphene layer integrated on top of a two-photonabsorption-free and low loss silicon-rich nitride core material at telecommunication wavelengths. An ultrahigh tuning efficiency (150 pm/V) over a tuning range of 1.3 nm, ensuring ultralow voltage consumption, was achieved in this work. We used titanium oxide and silicon oxide as the upper-cladding and under-cladding materials, respectively, around the silicon-rich nitride core material, to come up with a polarization-insensitive, and the thermally resilient third-orderadd-drop optical filter in the L band (1565 nm–1625 nm) with a full wave at a half maximum bandwidth of 50 GHz (linewidth of 0.4 nm) around 1570 nm, a high-free spectral range of 18.5 nm, a quality factor of 2580, an extinction ratio of 60 dB, a finesse of 19, and a thermal stability of 0.3 pm/K. A three-dimensional multiphysics approach was used to simulate the propagation of transverse electric and transverse magnetic polarized waves through the filter, combining the electromagnetic features with thermo-optic and stress-optical effects. The contribution of this work to the existing literature is that the designed filter proposes a new and highly tunable material system compatible with the complementary metal-oxide-semiconductor fabrication technology while combining high tunability, polarization insensitivity, and high thermal stability features for an ultracompact and energy-efficienton-chip integrated photonic tunable filter for dense wavelength division multiplexing systems in the less occupied L band.

Backscattering in nonlinear microring resonators via a Gaussian treatment of coupled cavity modes

Systems of coupled cavity modes have the potential to provide bright quantum optical states of light in a highly versatile manner. Microring resonators, for instance, are highly scalable candidates for photon sources. Thanks to CMOS fabrication techniques for their small footprint and the relative ease of coupling many such microrings together. However, surface roughness of the waveguides and defects in the coupler geometry routinely induce splitting of the cavity modes due to backscattering and backcoupling. The parasitic back-propagating mode in a microring leads to hybridization of the modes, altering the linear and nonlinear properties of a system of coupled cavity modes and ultimately constraining the fidelity of quantum light sources that can be produced. In this paper, we derive a comprehensive general model for Gaussian nonlinear processes in systems of coupled cavity modes based on an effective field Hamiltonian and a dispersive input–output model. The resulting dynamics of the equations of motion are evaluated in a Gaussian process formalism via symplectic transformations on the optical modes. We then use this framework to numerically model and explore the problem of backscattering in microring resonators in physically relevant parameter regimes, involving the splitting of various resonances, and we calculate the consequent impurity and heralding efficiency of various heralded photon schemes. We provide a perturbative explanation of the observations and assess the correspondence between spontaneous and stimulated processes in these systems.

Combining FDTD and coupled-mode theory for self-pulsing modeling in coupled nonlinear microring resonators

By means of finite-difference time-domain (FDTD) simulations, the stationary and dynamic responses of coupled optical microring resonators made with a material exhibiting an instantaneous Kerr nonlinearity are numerically investigated. We compare the results with the coupled-mode theory (CMT) and find good agreement. We demonstrate by integrating Maxwell’s equations that this system can show a self-pulsing operation in the normal dispersion regime. Finally, this work shows that FDTD simulations can be combined with a CMT analysis for the purpose of designing optical functions whose operation is based on nonlinear coupled micro-resonators.

Multi-frequency radiation of dissipative solitons in optical fiber cavities

New resonant emission of dispersive waves by oscillating solitary structures in optical fiber cavities is considered analytically and numerically. The pulse propagation is described in the framework of the Lugiato-Lefever equation when a Hopf-bifurcation can result in the formation of oscillating dissipative solitons. The resonance condition for the radiation of the dissipative oscillating solitons is derived and it is demonstrated that the predicted resonances match the spectral lines observed in numerical simulations perfectly. The complex recoil of the radiation on the soliton dynamics is discussed. The reported effect can have importance for the generation of frequency combs in nonlinear microring resonators.

Simulation of reconfigurable double-input optical gates based on a microring flower-like structure. part I. basic gates.

In this paper, a simulation and general analysis of nonlinear microring resonators (MRRs) as all-optical switches are discussed in a flower-like structure. These MRRs are modulated through an optical pump beam, which receives temporal shift of MRRs' resonance wavelengths. These shifts are a result of the refractive index changing due to carrier injection. A green laser is used as the optical pump to shift the resonant wavelength of each MRR. This proposed structure can operate as all-optical logic gates. Of those innovations are reconfigurable structure to achieve various gates, integrating capability, and a high extinction ratio between zero and one logical levels. This configuration would be useful to design optical integrated circuits.

Enhanced Small-Signal Responsivity in Silicon Microring Photodetector Based on Two-Photon Absorption

We experimentally investigated methods of enhancing the small-signal responsivity of a silicon pin microring photodetector based on two-photon absorption for detecting small optical signals in the telecommunication wavelength range. Two approaches are demonstrated, the first exploiting the bistability effect in the nonlinear microring resonator while the second employing an optical bias at a different wavelength to increase the differential responsivity. We achieved a small-signal responsivity of 180 mA/W with the first approach and 141 mA/W with the second approach, both of which represent almost 10-fold enhancement over direct detection of small optical signals by the same silicon pin microring detector. Our techniques have potential applications in amplitude demodulation, heterodyne detection, and optical power monitoring in WDM communication channels.

High performance RF filters via bandwidth scaling with Kerr micro-combs

We demonstrate high-resolution photonic RF filters using an RF bandwidth scaling approach based on integrated Kerr optical micro-combs. By employing both an active nonlinear micro-ring resonator (MRR) as a high-quality micro-comb source and a passive high-Q MRR to slice the shaped comb, a large RF instantaneous bandwidth of 4.64 GHz and a high resolution of 117 MHz are achieved, together with a broad RF operation band covering 3.28 to 19.4 GHz (L to Ku bands) using thermal tuning. We achieve programmable RF transfer functions including binary-coded notch filters and RF equalizing filters with reconfigurable slopes. Our approach is an attractive solution for high performance RF spectral shaping with high performance and flexibility.

Meditation mathematical formalism and Lorentz factor calculation based-on Mindfulness foundation

Abstract Mindfulness foundation is an excellent method of the human spiritual development by the reasonable thinking and consideration, which was established by Lord Buddha a long time ago. There are four ways of thinking and consideration-(i) form (body), (ii) sensation, (iii) spiritual and (iv) Dhamma. In this paper, we propose the use of the form consideration for the spiritual development, in which the form can be considered thoroughly inside the body by the spiritual projection. By using the nonlinear microring resonator known as a Panda-ring resonator, the electromagnetic (EM) signals called polaritons can be generated by the coupling interaction between the intense EM fields and the ionic diploes within the almost closed system, where the dipoles can obtain from the coupling between the gold grating and the strong electromagnetic fields. In the manipulation, cells, tissues, and organs inside the human body can communicate with the spiritual (polaritonic) signals and investigation. The simulation results obtained have shown that the Lorentz factor of 0.99999959 is obtained. The successively filtering of the signal circulation within the body during the meditation can be formulated and the meditation behaviors modeled. The aura, the stopping, and the cold body states can be configured and explained.

Simulation Results of Coherent Light in a Modified Microring Resonator

By using short Gaussian pulses from a monochromatic light source as input ones, we simulate the photon distribution and analyze the output signals of a nonlinear microring resonator with two nonlinear side rings. Such a configuration is called a Panda ring resonator, which is a modified add-drop filter with two alongside phase modulators. We consider the directional couplers, which are characterized by two parameters, i.e., the power coupling coefficient (к) and the power coupling loss (y). The nonlinear refractive index (n2) of the phase modulator affects the center ring and reveals more interesting aspects. The simulation model is constructed, and the results obtained with the use of a combination of the Lumerical FDTD and MODE programs are presented. The photon is conceptually interpreted in terms of a wave packet and discussed for possible applications.

Dual mode grating sensor using microring conjugate mirror and plasmonic island

AbstractIn this study, we propose a model for the dual mode gold grating sensor using a microring conjugate mirror (MCM) and the plasmonic island. The sensor measurement of derived quantity is the change in the Bragg wavelength and electron mobility that can be related to the optical phase‐shift or gold grating mobility changes. The plasmonic island consists of the stacked layers of silicon‐graphene‐gold materials. At the resonant condition, the gold electron mobility is driven by the whispering gallery mode generated by the nonlinear microring resonator. Additionally, the 3D reflection power profile of the grating sensor and target source interaction can be formed by the MCM. By selecting the suitable parameters, it can be arranged to have the four‐wave mixing output, which is the criterion of the 3D output of the MRC. The calculation results have shown that there is a relationship between the change in the electron mobility and Bragg wavelength of ~1.5 × 10−21 cm2 V−1 s−1 (mW)−1 at the λ Bragg of 1.55 μm, where the separation of 1 nm is obtained. The related mathematical formulas are re‐arranged for suitable applications.

Mode-locked self-pumping and squeezing photons model in a nonlinear micro-ring resonator

Photon squeezing and self-pumping within a nonlinear microring GaAsInP/P resonator are modeled and simulated, based on practical, published device parameters. A slowly varying amplitude pulse is input to the system, with a pulse width of 20 ns, a wavelength of 1.55 µm and peak power of 100 mW. The nonlinear effect resulting from the photons within the nonlinear ring resonator can be increased by adding external nonlinear coupling where, in this case, two nonlinear side rings are provided. The Dirac approach is used to generate the squeezed photons within the system. Three different device structures have been investigated, which include an add-drop filter, and a modified add-drop filter with two inner and outer side ring coupling resonators, where the nonlinear four-wave mixing effect is introduced. By using the commercial Opti-wave and MATLAB programs (in which suitable parameters have been chosen), the balance between the creation and annihilation operators can form the squeezed photons, which can be seen at the edge and center rings. The results obtained have shown that the squeezed center photon optical path (between 0 and 1 nm can be obtained) can be useful for interferometry, photon sources, and security code and sensor applications.

All-optical simultaneous AND & XOR logic gates based on nonlinear micro-ring resonator

ABSTRACTIn this paper, we have proposed AND and XOR logic gates simultaneously in one structure. The presented structure is based on two-dimensional (2D) nonlinear photonic crystal with T–shaped waveguide and micro-ring resonator. In the proposed structure, the power consumption is that is lower than similar logic gates and the extinction ratio is about 6.5 dB. Also, the switching time is attained to be 0.2 and 0.26 ps for AND and XOR logic gates, respectively. Simplicity and small size (18.4 µm×18.4 µm) of the structure make it suitable for photonic integrated circuits (PICs). All simulations are based on finite-difference time-domain (FDTD) and plane wave expansion (PWE) numerical methods.

On-chip polariton generation using an embedded nanograting microring circuit

Abstract We have proposed a model of polariton generation, which is normally generated by the dipole and the strong coupling field interaction. This system consists of a gold grating embedded on the plasmonic island, which is embedded at the center of the nonlinear microring resonator, which is known as a panda-ring resonator. The strong coupling between the plasmonic waves and the grating can be formed by the whispering gallery mode (WGM) of light within a Panda-ring resonator, in which the output is a dipole-like particle known as a polariton and seen at the system output. By varying the energy of high-intensity laser pulse in the system and gold granting a strong field is generated at the output. A dipole is formed by a pair of the grating signals, where one propagates in the opposite direction of the other. By using suitable parameters, dipole-like signals can be generated. Theoretical formulation is performed for a two-level system and polariton oscillation frequency i.e., the Rabi frequency is plotted. The obtained ground and excited state frequencies of this two-level system are 187.86 and 198.20 THz, respectively.

All-Optical Reservoir Computing on a Photonic Chip Using Silicon-Based Ring Resonators

We present in our work numerical results on the performance of a $\mathbf {4 \times 4}$ swirl-topology photonic reservoir integrated on a silicon chip. Nonlinear microring resonators are used as nodes. We analyze the performance of such a reservoir on a classical nonlinear Boolean task (the delayed XOR task) for: various designs of the reservoir in terms of lengths of the waveguides between consecutive nodes, and various injection parameters (injected power and optical detuning). From this analysis, we find that this kind of reservoir can perform–for a large variety of parameters–the delayed XOR task at 20 Gb/s with bit error rates lower than $\mathbf {10^{-3}}$ and an averaged injection power lower than 2.5 mW.

A microring conjugate mirror design and simulation for naked‐eye 3D imaging application

AbstractWe present a design of micro‐conjugate mirror using a nonlinear microring resonator, which is made of GaAsInP/P, is rapidly achieving widespread option in several three‐dimensional (3D) imaging applications. By exploiting the conjugate mirror properties, the 3D light probes can be formed by the whispering gallery modes (WGM) in which the WGM probe is also available within a nonlinear microring resonator. It is important to understand, these light probes use the similar functional principle to provide structured light through the object, just as the reference beams to light up and develop a hologram using the holographic method. The interference of 2 beams constructs the 3D image which can be seen by the naked‐eye while providing the 3D perception. The simulation results obtained from the transmission of 3D imaging are processed using MATLAB and OptiFDTD are compared and analyzed. These convincing theoretical results suggest that the proposed method can be used in practice to realize the naked‐eye 3D imaging with convincing visual perception and efficient transmission while providing the ultimate mode of convenience for viewers.

Engineering spectrally unentangled photon pairs from nonlinear microring resonators by pump manipulation.

The future of integrated quantum photonics relies heavily on the ability to engineer refined methods for preparing the quantum states needed to implement various quantum protocols. An important example of such states is quantum-correlated photon pairs, which can be efficiently generated using spontaneous nonlinear processes in integrated microring-resonator structures. In this work, we propose a method for generating spectrally unentangled photon pairs from a standard microring resonator. The method utilizes interference between a primary and a delayed secondary pump pulse to effectively increase the pump spectral width inside the cavity. This enables on-chip generation of heralded single photons with state purities in excess of 99% without spectral filtering.

Micro-optical probe model using integrated triple microring resonators for vertical depth identification

The nonlinear microring resonator system is designed and the triple vertically Panda rings arranged for 3D imaging probe generation. The required whispering gallery modes (WGM) probe can be generated by controlling the input soliton and the reflected power within the microring system. It can be configured to be a microring conjugate mirror (MCR) and theoretically confirmed by the obtained nonlinear four-wave mixing output. The different depths of the MCCs are arranged by the differences of the vertical heights, which can offer the triple vertical probe requirement. The analytical solution of the WGM probe output is derived and the selected simulation results investigated. The results obtained have shown that the triple WGM probes can be generated and used for the 3D imaging detection, from which the two surface depths are ~ 2 and 4 µm are plotted, the calculated and the different colored shades seen. In application, such a proposed system may be used for the 3D imaging of the soft tissues (cells) investigations.

Characteristics of microring circuit using plasmonic island driven electron mobility

The plasmonic electronic component consists of the stacked layers of silicon–graphene–gold materials can be integrated with the driven group velocity system, which is nonlinear microring resonator. This determines the suitable driven velocity in controlling the side ring phase modulators. In such a case, the proposed system can give the advantage of the greater switching speed and the hybrid function between electronic and light signals. The obtained I–V output characteristics of the transmitted results have shown that the proposed circuit can function to be the electronic devices with very high stability.

Naked-eye 3D imaging model using the embedded micro-conjugate mirrors within the medical micro-needle device

A micro-conjugate mirror (MCC) is designed and modified using a nonlinear microring resonator system, a system consists of a nonlinear microring resonator known as a Panda ring resonator. An MCC can be formed by adjusting the reflected light power from the Throughput and Add ports, from which the outputs can be detected by the Drop port output and 3D image construction can be performed. The short distance naked-eye 3D imaging transmission is accomplished, which can be confirmed by the four-wave mixing outputs, which is useful for 3D image transmission, bio-sensors and medical imaging and diagnostic applications.

Micro-Current Source Generated by a WGM of Light Within a Stacked Silicon-Graphene-Au Waveguide

A micro-current source using the drive electron mobility model is proposed by using the non-linear micro-ring resonator. The system consists of a nonlinear microring resonator known as Panda ring resonator made of InGaAsP/InP. The stacked waveguide (plasmonic island) of silicon-graphene-gold is formed at the center of the Panda ring, through which the whispering gallery mode (WGM) of light can be controlled and generated by the central ring it allows the driven electron mobility within the gold layer that can increase WGM beam acceleration and device current density with respect to the input optical power and ring parameters. The simulation results are obtained using the Opti-wave and MATLAB software programs. Results have shown that the relationship between the input of optical power and driven output current density can be obtained.