Real-time spectroscopy access to ultrafast fiber lasers opens new opportunities for exploring complex soliton interaction dynamics. Here, we have reported the first observation, best of our knowledge, entire buildup process molecules (SMs) in a mode-locked laser. We observed that birth dynamics stable SM experiences five different stages, i.e., raised relaxation oscillation (RO) stage, beating transient single pulse bound state, and finally state. discovered evolution pulses RO stage follows...

We propose a plasmonic nanosensor based on Fano resonance in the strong-confinement metal-dielectric-metal waveguide side-coupled with pair of nanoresonators. Due to coherent interference splitting discrete and quasi-continuum modes, reflection spectrum possesses sharp asymmetric dip, which is dependent cavity-cavity phase refractive index change dielectric. The physical features contribute highly efficient sensor for sensing. yields sensitivity ~900 nm/RIU figure merit ~500, remarkable...

We have theoretically and numerically investigated an analog of electromagnetically induced transparency (EIT) in plasmonic systems consisting multiple cascaded nanodisk resonators, aperture-side-coupled to metal-insulator-metal bus waveguides. A simplified theoretical model is established study spectral features the waveguide-resonator systems, calculated results are good agreement with finite-difference time-domain simulations. The main dependent factors EIT-like response, namely,...

A novel ultrafast all-optical switching based on metal-insulator-metal nanoplasmonic waveguide with a Kerr nonlinear resonator is proposed and investigated numerically. With the finite-difference time-domain simulations, it demonstrated that an obvious optical bistability of signal light appears by varying control-light intensity, excellent effect achieved. This originates from intensity-dependent change induced in dielectric constant material filled nanodisk resonator. It found exhibits...

A novel and simple plasmonic filter based on metal-insulator-metal waveguides with a nanodisk resonator is proposed investigated numerically. By the resonant theory of disk-shaped nanocavity, we find that resonance wavelengths can be easily manipulated by adjusting radius refractive index which in good agreement results obtained finite-difference time-domain (FDTD) simulations. In addition, bandwidths spectra are tunable changing coupling distance between nanocavity waveguides. This result...

Abstract Harmonic mode‐locking (HML) is an important technique enabling the generation of high‐repetition‐rate ultrashort pulses. Using emerging time‐stretch dispersive Fourier transform technique, experimental observation entire buildup process passive HML state in ultrafast fiber laser reported here. It unveiled that whole successively undergoes seven different phases: raised relaxation oscillation, spectral beating behavior, birth a giant pulse, self‐phase‐modulation‐induced instability,...

The tunable multi-channel wavelength demultiplexer (WDM) based on metal-insulator-metal plasmonic nanodisk resonators is designed and numerically investigated by utilizing Finite-Difference Time-Domain (FDTD) simulations. It found that the channel of WDM easily tuned changing geometrical parameters structure material filled in resonator. consisting a waveguide several increases transmission up to 70% at telecommunication regime, which two times higher than results reported recent literature...

Q switching (QS) and mode locking (ML) are the two main techniques enabling generation of ultrashort pulses. Here, we report first observation pulse evolution dynamics in QS-ML transition stage, where ML soliton formation evolves from QS pulses instead relaxation oscillations (or quasi-continuous-wave oscillations) reported previous studies. We discover a new way buildup an ultrafast laser, passing through four stages: initial spontaneous noise, QS, beating dynamics, ML. reveal that multiple...

Real-time spectroscopy based on an emerging time-stretch technique can map the spectral information of optical waves into time domain, opening several fascinating explorations nonlinear dynamics in mode-locked lasers. However, self-starting process lasers is quite sensitive to environmental perturbation, which causes transient behaviors deviate from true buildup solitons. We optimize laser system improve its stability, suppresses Q-switched lasing induced by perturbation. We, therefore,...

Based on the fiber Bragg gratings (FBGs) and high nonlinear photonic crystal (HN-PCF), a novel dual-wavelength erbium-doped (EDF) laser is proposed demonstrated. The experimental results show that, owing to contributions of two degenerate four-wave mixings in HN-PCF, great stable output signals are uniform at room temperature. With adjustment attenuator, our can selectively realize one wavelength lasing.

An optical effect analogous to electromagnetically induced transparency (EIT) is observed in nanoscale plasmonic resonator systems. The system consists of a slot cavity as well bus and resonant waveguides, where the phase-matching condition waveguide tunable for generation an obvious EIT-like coupled resonator-induced effect. A dynamic theory utilized exactly analyze influence physical parameters on transmission characteristics. by resonance may have potential applications switching,...

We have proposed a metal-insulator-metal (MIM) waveguide system, which exhibits significant slow-light effect, based on plasmonic analogue of electromagnetically induced transparency (EIT). By appropriately adjusting the distance between two stubs unit cell, flat band corresponding to nearly constant group index over broad bandwidth 8.6 THz can be achieved. The analytical results show that velocity dispersion (GVD) parameter reach zero and normalized delay-bandwidth product (NDBP) is more...

We have proposed a novel type of bandpass plasmonic filter consisting metal–insulator–metal bus waveguides coupled with series side-coupled cavities and stub waveguides. The theoretical modeling demonstrates that our waveguide-resonator system performs analogue electromagnetically induced transparency (EIT) in atomic systems, as is confirmed by numerical experiments. EIT-like response enables the realization nanoscale filters multiple channels. Additionally, operating wavelengths bandwidths...

Abstract Monolayer of transition metal dichalcogenides (TMDs), with lamellar structure as that graphene, has attracted significant attentions in optoelectronics and photonics. Here, we focus on the optical absorption response a new member TMDs, rhenium disulphide (ReS 2 ) whose monolayer bulk forms have nearly identical band structures. The nonlinear saturable polarization-induced ReS are investigated at near-infrared communication beyond its bandgap. It is found -covered D-shaped fiber...

All the optical properties of materials are derived from dielectric function. In spectral region where permittivity approaches zero, known as epsilon-near-zero (ENZ) region, propagating light within material attains a very high phase velocity, and meanwhile exhibits strong nonlinearity. The interplay between linear nonlinear response in these thus offers unprecedented pathways for all-optical control device design. Here authors demonstrate ultrafast modulation based on typical ENZ indium tin...

We demonstrate the existence of multiple electromagnetically induced transparencies (EIT)-like spectral responses in graphene metamaterials consisting a series self-assembled Fabry-Pérot (FP) cavities. By exploiting plasmon resonances and phase-coupling effects, transfer matrix model is established to theoretically predict EIT-like responses, calculated results coincide well with numerical simulations. It found that high-contrast (~90%) windows are observed over broad range mid-infrared....

We investigate the properties of spatial solitons in fractional Schrodinger equation (FSE) with parity-time (PT)-symmetric lattice potential supported by focusing Kerr nonlinearity. Both one- and two-dimensional can stably propagate PT-symmetric lattices under noise perturbations. The domains stability for both strongly depend on gain/loss strength lattice. In domain, are rigidly modulated weak diffraction FSE systems. inverse space, due to periodicity lattices, spectra experience sharp...

We propose and numerically investigate a novel kind of nanoscale plasmonic wavelength demultiplexing (WDM) structure based on channel drop filters in metal-insulator-metal waveguide with reflection nanocavities. By using finite-difference time-domain simulations, it is found that the transmission efficiency filter can be significantly enhanced by selecting proper distance between cavities. The result exactly analyzed temporal coupled-mode theory. According to this principle,...

Based on a two-dimensional plasmonic metal-dielectric-metal (MDM) waveguide with thin metallic layer and dielectric photonic crystal in the core, novel absorber at visual near-infrared frequencies is presented. The spectra filed distributions are investigated by transfer-matrix-method finite-difference time-domain method. Numerical results show that attributing to excitation of optical Tamm states MDM wave trapped proposed structure without reflection transmission, leading perfect absorption...

Surface plasmon polariton reflector (SPPR) based on metal-insulator-metal (MIM) Bragg grating waveguide is numerically studied. A quasi-chirped technique applied to the engraved grooves in surface of MIM waveguide, and a new kind broad-bandgap SPPR achieved. Meanwhile, by optimizing profile gap width between metal dielectric, spectral sidelobe effectively suppressed thus performance o f further improved.

We have investigated the generation and propagation of robust bound-state pulses emitted from a passively mode-locked figure-eight laser with net-anomalous dispersion. Two pulse duration 1.3 ps separation 2.2 exhibit strongly modulated spectral profile. The experimental observations show that increase approximately linearly along extracavity single-mode fiber (SMF). are broadened by factor 7 5.7, respectively, after pair propagates through standard SMF 202 m. theoretical results well agree...

We have proposed a graphene-integrated Fabry-Pérot microcavity for efficient modulation of spatial light. A simplified theoretical model is established to analyze the performance our system, and calculated results agree well with simulation results. It shown that plasmon-induced transparency (PIT) effect achieved in central frequency PIT window can be dynamically tuned by gate voltages. In particular, spectra exhibit extremely large depths (∼90%) across broad range frequencies. The...

We have proposed a graded grating plasmonic system with significant slow-light effect for the propagation of high-confinement surface plasmon (SP) wave. Theoretical analysis and numerical simulations show that localized position SP wave in waveguide is dependent on operating frequency. It found exhibits an obvious enhancement propagation. The ultracompact configuration offers advantage large trapping bandwidth 90 THz, which may find excellent applications systems, especially optical buffers.

We address the existence and stability of off-site on-site vortex solitons with a unit topological charge in space-fractional Kerr lattices. In contrast to reported ordinary lattices, proposed lattices are stable only intermediate region propagation constant, this widens rapidly increase Lévy index. Under same index, range vortices is larger than that ones. particular, for solitons, upper edge appears where maximum soliton power located, which provides an effective way identify vortices. Our...

Abstract The field of nonlinear optics has grown substantially in past decades, leading to tremendous progress fundamental research and revolutionized applications. Traditionally, the optical nonlinearity for a light wave at frequencies beyond near-infrared is observed with very high peak intensity, as most materials only electronic dominates while ionic contribution negligible. However, it was shown that can be much larger than one microwave experiments. In terahertz (THz) regime, phonon...