Four-wave Mixing Phenomenon Research Articles

Four-wave mixing temperature sensor based on graphene oxide-coated microfiber hybrid waveguide

Utilizing a hybrid waveguide comprising microfiber and graphene oxide (GO), this study introduced an innovative temperature sensor based on four-wave mixing (FWM) effect. The methodology involved a tunable continuous wave (TCW) laser and a self-engineered all-fiber mode-locked laser operating at 1560 nm. The microfiber, featuring a minimum diameter of 10 μm, was fabricated through the flame fusion tapering technique, and the microfiber surface was coated with a GO film through the spontaneous evaporation of a GO solution. To improve the stability and robustness of the sensor, a layer of polydimethylsiloxane (PDMS) was applied to the surface as a protective coating. The GO film compensated for dispersion in conjunction with microfiber, enhanced nonlinearity and facilitated low-power FWM phenomena. Furthermore, it increased temperature sensing sensitivity. By measuring the center wavelength shift of the idler and signal light, we achieved a temperature sensing sensitivity of −2.08 nm/℃ from −15 ℃ to 20 ℃ using the CW laser at 1540 nm. This sensor also had a resolution of 0.024 ℃, a response time of 0.12 s and a maximum temporal resolution of 0.08 s. Our study marks the initial investigation of a temperature sensing mechanism employing the FWM phenomenon within this unique hybrid waveguide. It serves as a proof of concept for using a microfiber combined with the two-dimensional material GO film to generate nonlinear FWM for temperature sensing. Continuous optimization of experimental conditions and waveguide dimensions is expected to enhance sensing performance. This opens up new avenues for future research in novel optical sensing technology, particularly in the exploration of high-performance sensors through the integration of nonlinear phenomena with different two-dimensional materials, showcasing substantial research potential.

Controllable Fano-type optical response and four-wave mixing via magnetoelastic coupling in an opto-magnomechanical system

We analytically investigate the Fano-type optical response and the four-wave mixing (FWM) process by exploiting the magnetoelasticity of a ferromagnetic material. The deformation of the ferromagnetic material plays the role of mechanical displacement, which is simultaneously coupled to both optical and magnon modes. We report that the magnetostrictively induced displacement leads to realization of Fano profiles in the output field and is effectively well-tuned through adjusting the system parameters, such as effective magnomechanical coupling, magnon detuning, and cavity detuning. It is found that the magnetoelastic interaction also gives rise to the FWM phenomenon. The number of the FWM signals mainly depends upon the effective magnomechanical coupling and the magnon detuning. Moreover, the FWM spectrum exhibits suppressive behavior upon increasing (decreasing) the magnon (cavity) decay rate. The present scheme will open new perspectives in highly sensitive detection and quantum information processing.

Mitigation of non-linear four-wave mixing phenomenon in a fully optical communication system

This paper aims to point out the nonlinear phenomenon occurring in coarse/dense wavelength division multiplex (C/D-WDM) systems. This phenomenon has to betaken into account during the design of the optical network itself, as wavelengthsin the optical fiber are constantly densified. The paper points out the emergence of the non-linear four-wave mixing (FWM) phenomenonand how it relates to the dispersion in the optical fiber together with the transmit power. The output of the paper is a proposed design of the system that points to the improvement of the bit error rate (BER) with a suitable choice of dispersion and suitable transmission power.

Stimulated four-wave mixing in the cascade-type atomic system of a warm Cs atomic ensemble.

We investigate stimulated four-wave mixing (FWM) in the 6S1/2-6P3/2-8S1/2 open transition of a warm 133Cs atomic ensemble. Despite the absence of the two-photon cycling transition, we measure high-contrast FWM signals in the 6P3/2-8S1/2 transition between the upper excited states according to the frequency detuning and powers of the coupling and driving lasers. The FWM light generation in the upper excited states is interpreted as the FWM phenomena induced by the driving laser of the 6S1/2-6P3/2 transition from the cascade-type two-photon coherent atomic ensemble with the coupling and pump lasers. We believe that this work can contribute to the development of hybrid photonic quantum networks between photonic quantum states generated from different atomic systems.

Four‐Wave Mixing Response via Hybrid Coulomb‐Coupled Cavity Optomechanics

AbstractThe generation and manipulation of the four‐wave mixing (FWM) phenomenon is reported in a hybrid electrostatically Coulomb‐coupled optomechanical system as a result of light–matter interaction. The cavity is driven by a strong coherent pump and a weak probe field simultaneously in the presence of nanomechanical resonators (NMRs), and the output field can produce a new frequency component called the FWM frequency. In a hybrid Coulomb‐coupled cavity scheme, the existence of optomechanical coupling due to radiation pressure gives rise to the FWM phenomenon, which is shown both analytically and numerically. A controllable enhancement of the FWM intensity is found by tuning the pump field strength and its spectrum disappears upon switching the strength off. A significant enhancement in the FWM spectrum with two peaks is also predicted due to the Coulomb coupling strength existing between two electrostatically coupled NMR1 and NMR2. A suppressive behavior of the FWM signal is also observed upon increasing the cavity decay rate and a substantial modulation in the signal by changing the probe‐pump field detuning. Finally, the FWM spectrum is very sensitive to both the effective resonance frequencies and effective masses of the NMRs.

Multiple modal and wavelength conversion process of a 10-Gbit/s signal in a 6-LP-mode fiber.

We demonstrate experimentally a simultaneous threefold modal and wavelength conversion process of a 10-Gbit/s On/Off keying signal in a 1.8-km long graded-index 6-LP-mode fiber. The principle of operation is based on a phase-matched inter-modal four-wave mixing phenomenon occurring between the fundamental mode and 3 higher-order modes of the fiber. The converted signals show well-opened eye-diagrams and error-free processing.

FWM in DCF based four-input all-optical NOR/AND gate

A simple four-input all-optical NOR/AND logic gate is simulated and evaluated. The design module is polarization dependent because of the four-wave mixing phenomenon applied to a dispersion compensation fiber. A successful logic function is obtained with a relatively simple simulation setup and low power requirements. With an optimized data signal power of 0.5 mW and probe power of 0.06 mW at a prominent BER with extinction ratio (ER) > 16 dB, a noticeably low harmonic-level indicator of the output logic pulse is achieved. A comparison with related studies is presented to explore the merits of this work.

Multimode four-wave mixing in an unresolved sideband optomechanical system

We have studied multimode four-wave mixing (FWM) in an unresolved sideband cavity optomechanical system. The radiation pressure coupling between the cavity fields and multiple mechanical modes results in the formation of a series of tripod-type energy-level systems, which induce the multimode FWM phenomenon. The FWM mechanism enables remarkable amplification of a weak signal field accompanied by the generation of an FWM field when only a microwatt-level pump field is applied. For proper system parameters, the amplified signal and FWM fields have equal intensity with opposite phases. The gain and frequency response bandwidth of the signal field can be dynamically tuned by varying the pump intensity, optomechanical coupling strength, and additional feedback control. Under certain conditions, the frequency response bandwidth can be very narrow and reaches the level of hertz.

Effect of four-wave mixing interference on spectrally separated channels in passive optical networks

The phenomenon of four-wave mixing in passive optical networks with wavelength-division multiplexing of channels has been studied. This paper presents the results of modeling the distribution of combination frequencies over the spectrum as a function of the number of channels and the channel frequency spacing. To suppress crosstalk between the channels at combination frequencies, it is proposed to divide the spectrum into two parts and select a guard band between them. The effect of combination frequencies on the signal transmission quality is considered as a function of the channel power, channel frequency spacing, and transmission length.

Geometric interpretation of four-wave mixing

The nonlinear phenomenon of four-wave mixing (FWM) is investigated using a method, where, without the need of calculus, both phase and amplitudes of the mixing fields are visualized simultaneously, giving a complete overview of the FWM dynamics. This is done by introducing a set of Stokes-like coordinates of the electric fields, which reduce the FWM dynamics to a closed two-dimensional surface, similar to the Bloch sphere of quantum electrodynamics or the Pointcar\'e sphere in polarization dynamics. The coordinates are chosen so as to use the gauge invariance symmetries of the FWM equations which also give the conservation of action flux known as the Manley-Rowe relations. This reduces the dynamics of FWM to the one-dimensional intersection between the closed two-dimensional surface and the phase-plane given by the conserved Hamiltonian. The analysis is advantageous for visualizing phase-dependent FWM phenomena which are found in a large variety of nonlinear systems and even in various optical communication schemes.

On the Nonlinear Mechanoplasmonic Theory of Frequency Scaling and Mixing Effects

In this work, the theoretical model explaining the frequency scaling and multi photon effects in metal nanoparticles has been suggested. Its capabilities are demonstrated in relation to the second and third harmonic generation phenomena and the four-wave mixing phenomena as well. The continuum mechanical description of the electron gas of valence electrons underlies the theory. The principal equations of motion are deduced by the Hamilton’s least action principle. The compatibility of the model with the Drude theory is demonstrated in the linear case. On the basis of the proposed model, we investigate the effect of Coulomb interaction in clusters of metal nanoparticles and the resulting motion of particles under the assumption of the compliance of an ambient medium.

Radio over Fiber Networks Synthesis Using Meta-Heuristic BCO

Radio access network over fiber (RoF) technology combines both wireless and fiber-optic technology. The advantages of this technology are low attenuation, bigger network bandwidth, easy installation and management, reduced power consumption, multiservice, dynamic allocation of resources. There are many methods of designing optical and wire-less networks. Since RoF combines these technologies, the design tasks are a complex problem. Therefore there is a need for a new design method for RoF technology. The main problem in designing DWDM transport networks is the wavelength assignment of light paths. If the network topology has a great need to use heuristic methods there is one way to solve this problem: use of the BCO-RWA algorithm. Meta-based heuristic algorithm BCO-RWA contains the modeling of the beha-vior of bees collecting nectar. The main advantage of this algorithm is low computational complexity. However, BCO-RWA has the following disadvantage: during the calculation of route selection probability, base algorithm does not take into account the nonlinear four-wave mixing phenomenon. In this paper we present new method to design RoF network and modification of BCO-RWA algorithm.

Wave mixing in nonlinear magnetic metacrystal

We present experimental measurements of three- and four-wave mixing phenomena in an artificially structured nonlinear magnetic metacrystal at microwave frequencies. The sum frequency generation signal for the varactor-loaded split-ring resonator (VLSRR) metamaterial agrees quantitatively with that predicted using an analytical effective medium model describing the VLSRR medium. A resonant enhancement of the nonlinear response is observed near the metamaterial resonance.

Distribution planning in design wavelength DWDM transport network

The mathematical formulation of the distribution of wavelengths of light paths optic communication channels of the transport network, taking into account four-wave mixing phenomenon. Proposed method of distribution of wavelengths, which allows for nonlinear four-wave mixing phenomenon by introducing additional constraints

Semiconductor optical amplifier-based multi-wavelength ring laser utilizing photonic crystal fiber

A multi-wavelength laser source is demonstrated with a semiconductor optical amplifier (SOA) as a gain medium. A multi-wavelength comb with equal spacing is achieved due to Fabry–Pérot modes of the SOA which oscillates in the ring cavity. A 100 m long photonics crystal fiber (PCF) is inserted in the ring cavity to provide a nonlinear gain by four-wave mixing (FWM) so that the output comb spectrum can be greatly broadened and flattened. The stability of the ring laser is also increased due to the efficient FWM phenomenon occurring in the PCF. The SOA-based laser can generate 35 lasing lines with equal spacing of 0.28 nm and extinction ratios of more than 30 dB at room temperature. The number of channels of the multi-wavelength laser can be controlled flexibly by changing the ratio of the coupler used in the ring cavity configuration as well as controlling the polarization state of the oscillating laser.

Four-wave mixing in silicon wire waveguides

We report the observation of four-wave mixing phenomenon in a simple silicon wire waveguide at the optical powers normally employed in communications systems. The maximum conversion efficiency is about -35 dB in the case of a 1.58-cm-long silicon wire waveguide. The nonlinear refractive index coefficient is found to be 9x10-18 m2/W. This value is not negligible for dense wavelength division multiplexing components, because it predicts the possibility of large crosstalk. On the other hand, with longer waveguide lengths with smaller propagation loss, it would be possible to utilize just a simple silicon wire for practical wavelength conversion. We demonstrate the wavelength conversion for data rate of 10-Gbps using a 5.8-cm-long silicon wire. These characteristics are attributed to the extremely small core of silicon wire waveguides.

Measurement of spectral lines produced by four-wave mixing in 30 km dispersion-shifted single-mode optical fiber

Interaction between two copropagating narrowband light waves in a monomode optical fiber can occur because of four-wave mixing phenomena. Light beams from two lasers, a tunable external cavity laser and a distributed feedback semiconductor laser with wavelength separation around 0.36 nm (45 GHz) at λ=1.545 μm, are first amplified by an erbium-doped amplifier and then launched into a 30 km dispersion-shifted fiber. The fiber acts as a nonlinear medium to mix two optical waves and generates one, two, three, and even four optical waves (sidebands) at other wavelengths. An optical spectrum analyzer with a resolution of 0.1 nm has been used to measure the power of the output sidebands. In good agreement with theory, by raising the power of input signals, the number of output sidebands and their powers is also increased.

Vibrational second hyperpolarizability of symmetrically substituted `quadrupolar' π-conjugated systems

Calculations of the electronic and vibrational second hyperpolarizabilities of various quadrupolar π-conjugated molecules performed at the ab initio Hartree-Fock level of approximation show that the vibrational contribution is large for most nonlinear optical phenomena. As for unsubstituted π-conjugated compounds, the Raman term which contributes to the dc-Kerr and degenerate four-wave mixing phenomena is of the same order of magnitude as the static electronic counterpart. The term related to the infrared and hyper-Raman intensities is substantial and, in the case of a squaraine dye, dictates the sign of the global response. This infrared-hyper-Raman term which is often negligible for unsubstituted compounds contributes substantially to the vibrational dc-Kerr and electric field-induced second harmonic generation responses.

Novel four-wave mixing phenomenon in a Raman amplifier.

We report on an investigation of second Stokes generation in a Raman amplifier, during which we observed a pattern of narrow, approximately radial lines in the second Stokes far-field distribution. This previously unreported phenomenon, and other features in the far field, can be explained by a combination of diffuse scattering and four-wave mixing.

Coherent and incoherent specular inverse Faraday effect: χ^(3) measurements in opaque materials

We report what is to our knowledge the first observation of coherent and incoherent terms of the specular inverse Faraday effect. The specular inverse Faraday effect is treated as a four-wave mixing phenomenon, and the role of the phase-conjugated wave in the polarization-altering interaction is disclosed. Several components of the nonresonant cubic susceptibility tensor in InSb and GaAs are measured and found to be in the 10(-7)-10(-6)-esu range.