Journal of Nonlinear Optical Physics & Materials最新文献

{"title":"Analysis of highly efficient DFG in an electro-optic material exhibiting polarization rotation using TIR-based ORQPM technique","authors":"M. Saha, S. Deb","doi":"10.1142/s0218863522500011","DOIUrl":"https://doi.org/10.1142/s0218863522500011","url":null,"abstract":"This paper is a numeric-analytical work for highly efficient difference-frequency generation (DFG) by the integrated effect of total-internal-reflection-based optical rotation quasi-phase-matching (ORQPM) and nonresonant quasi-phase-matching techniques in a thin yttrium oxide-coated rectangular slab of magnesium oxide-doped lithium niobate crystal. The conversion efficiency of 37.2% has been obtained by ray-optics analysis, corresponding to an idler wavelength of 1570[Formula: see text]nm. Moreover, the guided-wave approach has also been analyzed for more accurate and realistic outcomes, yielding a peak conversion efficiency of 1.64%. The impact of the influencing factors like surface roughness, absorption, and nonlinear law of reflection has also been incorporated in the computer-aided simulation for providing a pragmatic understanding of the whole study.","PeriodicalId":16520,"journal":{"name":"Journal of Nonlinear Optical Physics & Materials","volume":"101 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2021-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75736170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis, characterization, and femtosecond third-order optical nonlinearity of Au@Ag core–shell nanoparticles","authors":"Heng Lu, B. Gu","doi":"10.1142/s0218863522500023","DOIUrl":"https://doi.org/10.1142/s0218863522500023","url":null,"abstract":"In this work, the Au@Ag bimetallic core–shell nanostructures were synthesized by a seed-mediated growth. The crystal structure, morphology, elemental composition, atomic concentration, and absorption spectrum of the as-synthesized nanoparticles were characterized by means of X-ray diffraction, transmission electron microscopy, energy dispersive spectroscopy, X-ray photoelectron spectroscopy, and ultraviolet–visible linear absorption spectrum, respectively. The femtosecond third-order optical nonlinearities of nanoparticle dispersions were investigated by carrying out the femtosecond-pulsed [Formula: see text]-scan measurements at 800[Formula: see text]nm. The experimental results indicate that Au@Ag core–shell nanoparticles exhibit the positive refractive nonlinearity and negative absorptive nonlinearity. The third-order nonlinear refraction indexes of Au and Au@Ag nanoparticles are measured to be [Formula: see text] and [Formula: see text][Formula: see text]cm2/GW, respectively. The results show that the bimetallic nanoparticle has potential possibility in nonlinear photonic applications.","PeriodicalId":16520,"journal":{"name":"Journal of Nonlinear Optical Physics & Materials","volume":"49 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2021-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75307809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Controllable optical bistability based on rotation in semiconductor micro-cavity","authors":"K. Mukherjee, Anjan Samanta, P. Jana","doi":"10.1142/s0218863521500120","DOIUrl":"https://doi.org/10.1142/s0218863521500120","url":null,"abstract":"In this paper, we discuss a possibility to realize the optical bistability in a rotating semiconductor micro-cavity system. To study the mean cavity photon number profile, we have obtained stationary solution by solving Heisenberg–Langevin equations of motion. In a rotating semiconductor micro-cavity system, bistability is observed when the cavity is driven externally in one direction but not the other direction. The bistable behavior is possible for strong coupling regime, and this can be controlled by hopping strength, decay rates and pump power. The photon profile also shows tunable zero intensity window. The system may be useful to design all-optical switch and optical flip–flop i.e., optical memory element, which would be faster in applications and compact in size.","PeriodicalId":16520,"journal":{"name":"Journal of Nonlinear Optical Physics & Materials","volume":"71 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2021-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85881049","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In situ x-ray computed tomography of zinc–air primary cells during discharge: correlating discharge rate to anode morphology","authors":"J. Hack, Drasti Patel, J. Bailey, F. Iacoviello, P. Shearing, D. Brett","doi":"10.1088/2515-7639/ac3f9a","DOIUrl":"https://doi.org/10.1088/2515-7639/ac3f9a","url":null,"abstract":"Zinc–air batteries have gained significant attention as safe battery alternatives, with high theoretical energy densities and a high abundance of their constituent materials. However, barriers to their widespread adoption include the need to improve their cycling lifetime, as well as stability and avoiding degradation mechanisms such as zinc dendrite growth and hydrogen-producing side reactions. X-ray computed tomography (CT) is a widely used technique for the study of batteries. In situ / operando x-ray CT has been increasingly used to study the zinc anode of zinc–air batteries to evaluate the interesting morphological changes occurring during the reaction from zinc (Zn) to zinc oxide (ZnO) during discharge (vice versa during charge). However, several studies have been carried out using synchrotron x-ray sources, which have limited availability for users. In this work, we present a comprehensive study of the discharge of commercial, primary zinc–air batteries using a laboratory-based x-ray source for in situ x-ray CT measurements. Four different discharge rates are investigated (C/30, C/60, C/90 and C/150), with tomograms collected at various stages throughout each discharge. Results confirm that with decreasing C-rate (i.e. decreasing discharge current) a greater volume of zinc is reacted, with average mass utilisations of 17%, 76%, 81% and 87% for C/30, C/60, C/90 and C/150, respectively. Furthermore, quantification using x-ray CT datasets showed that there is a direct correlation between the volume of zinc remaining in the cell and the state-of-charge of the cell, which deviated from linearity for the longer C-rates. Finally, a potential new mechanism for shape change is discussed, where a Zn particle is replaced with a pore of a similar volume. As well as improvements in statistical relevance gained from multiple repeats for each C-rate, the results presented here could be used in both modelling of battery performance, as well as consideration for future anode design concepts.","PeriodicalId":16520,"journal":{"name":"Journal of Nonlinear Optical Physics & Materials","volume":"88 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2021-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81174545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dirac materials under linear polarized light: quantum wave function time evolution and topological Berry phases as classical charged particles trajectories under electromagnetic fields","authors":"V. G. Ibarra-Sierra, J. C. Sandoval-Santana, A. Kunold, Sa'ul A. Herrera, G. Naumis","doi":"10.1088/2515-7639/ac5231","DOIUrl":"https://doi.org/10.1088/2515-7639/ac5231","url":null,"abstract":"\u0000 The response of electrons under linearly polarized light in Dirac materials as borophene or graphene is analyzed in a continuous wave regime for an arbitrary intense field. Using a rotation and a time-dependent phase transformation, the wave function evolution is shown to be governed by a spinor-component decoupled Whittaker-Hill equation. The numerical solution of these equations enables to find the quasienergy spectrum. For borophene it reveals a strong anisotropic response. By applying an extra unitary transformation, the wave functions are proven to follow an Ince equation. The evolution of the real and imaginary parts of the wave function is interpreted as the trajectory of a classical charged particle under oscillating electric and magnetic field. The topological properties of this forced quantum system are studied using this analogy. In particular, in the adiabatic driving regime, the system is described with an effective Matthieu equation while in the non-adiabatic regime the full Whittaker-Hill equation is needed. From there, it is possible to separate the dynamical and Berry phase contributions to obtain the topological phase diagram due to the driving. Therefore, a different path to perturbation theory is developed to obtain time-driven topological phases.","PeriodicalId":16520,"journal":{"name":"Journal of Nonlinear Optical Physics & Materials","volume":"12 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83397794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phoebe: a high-performance framework for solving phonon and electron Boltzmann transport equations","authors":"Andrea Cepellotti, J. Coulter, A. Johansson, N. Fedorova, B. Kozinsky","doi":"10.1088/2515-7639/ac86f6","DOIUrl":"https://doi.org/10.1088/2515-7639/ac86f6","url":null,"abstract":"Understanding the electrical and thermal transport properties of materials is critical to the design of electronics, sensors, and energy conversion devices. Computational modeling can accurately predict material properties but, in order to be reliable, requires accurate descriptions of electron and phonon states and their interactions. While first-principles methods are capable of describing the energy spectrum of each carrier, using them to compute transport properties is still a formidable task, both computationally demanding and memory intensive, requiring integration of fine microscopic scattering details for estimation of macroscopic transport properties. To address this challenge, we present Phoebe—a newly developed software package that includes the effects of electron–phonon, phonon–phonon, boundary, and isotope scattering in computations of electrical and thermal transport properties of materials with a variety of available methods and approximations. This open source C++ code combines MPI-OpenMP hybrid parallelization with GPU acceleration and distributed memory structures to manage computational cost, allowing Phoebe to effectively take advantage of contemporary computing infrastructures. We demonstrate that Phoebe accurately and efficiently predicts a wide range of transport properties, opening avenues for accelerated computational analysis of complex crystals.","PeriodicalId":16520,"journal":{"name":"Journal of Nonlinear Optical Physics & Materials","volume":"122 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85706677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Have Mysterious Topological Valley Currents Been Observed in Graphene Superlattices?","authors":"S. Roche, S. R. Power, Branislav K. Nikoli'c, Jose H. Garcia, A. Jauho","doi":"10.1088/2515-7639/ac452a","DOIUrl":"https://doi.org/10.1088/2515-7639/ac452a","url":null,"abstract":"\u0000 We provide a critical discussion concerning the claim of topological valley currents, driven by a global Berry curvature and valley Hall effect proposed in recent litterature. After pointing out a major inconsistency of the theoretical scenario proposed to interpret giant nonlocal resistance, we discuss possible alternative explanations and open directions of research to solve the mystery of nonlocal transport in graphene superlattices.","PeriodicalId":16520,"journal":{"name":"Journal of Nonlinear Optical Physics & Materials","volume":"248 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2021-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78839610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of piezoelectricity, doping and magnetostatic field on Brillouin amplification in compound (AIIIBV and AIIBVI) semiconductors","authors":"Arun Kumar, S. Dahiya, Navneet Singh, Manjeet Singh","doi":"10.1142/s0218863521500107","DOIUrl":"https://doi.org/10.1142/s0218863521500107","url":null,"abstract":"A theoretical formulation followed by numerical analysis describing Brillouin amplification in compound (AIIIBV and AIIBVI) semiconductors is explored. The threshold condition for the onset of Brillouin amplification is determined. Well above the threshold intensity, the influence of piezoelectricity, doping concentration, and external magnetostatic field on the parameters characterizing Brillouin amplification viz. Brillouin amplification coefficient, transmitted intensity of Brillouin-scattered Stokes mode (BSSM), and Brillouin cell efficiency of the Brillouin cell isestimated. Numerical analysis is made for three different Brillouin cells consisting of [Formula: see text]-InSb, [Formula: see text]-GaAs, and [Formula: see text]-CdS, at 77[Formula: see text]K duly irradiated by a pulsed CO2 laser. Efforts are directed towards to determine appropriate values of doping concentration and magnetostatic field to enhance the parameters characterizing Brillouin amplification, at lower excitation intensity, and to establish the suitability of compound semiconductors as hosts for fabrication of efficient Brillouin amplifiers.","PeriodicalId":16520,"journal":{"name":"Journal of Nonlinear Optical Physics & Materials","volume":"1 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2021-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75431405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modulation instability in the presence of slowly varying saturable nonlinearity, dispersion and a PT-symmetric external potential over the length of waveguide","authors":"V. Sharma","doi":"10.1142/s0218863521500090","DOIUrl":"https://doi.org/10.1142/s0218863521500090","url":null,"abstract":"We study the modulation instability (MI) for optical wave propagation in the presence of slowly varying saturable nonlinearity, group velocity dispersion and a PT-symmetric external potential over the length of tapered graded-index waveguide. First we study the MI with space-dependent dispersion and saturated nonlinearity and then with constant dispersion and saturated nonlinearity. We analytically compute the growth rate and analyze the possibility of existence of MI for focussing and defocussing nonlinearities for different choices of group velocity dispersion terms and saturated nonlinearities. We observe that MI is independent of PT symmetric potential term and typically depends upon the choice of group velocity dispersion term, nonlinearity, saturated nonlinearity and wave amplitude. MI gain decreases with increase in cw amplitude however it increases with increase in saturated nonlinearity both for focussing and defocussing nonlinearities.","PeriodicalId":16520,"journal":{"name":"Journal of Nonlinear Optical Physics & Materials","volume":"21 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2021-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83217818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nonlinear optical responses of molecular systems with vibronic coupling in fluctuating environments","authors":"J. L. Paz, M. Loroño, Lenin A. González-Paz, E. Márquez, J. Vera-Villalobos, J. Mora, Y. Alvarado","doi":"10.1142/s0218863521500119","DOIUrl":"https://doi.org/10.1142/s0218863521500119","url":null,"abstract":"The topological profiles of the nonlinear optical properties of a two-level molecular system involving simplified versions of intramolecular coupling immersed in a thermal reservoir have been studied in four-wave mixing (FWM) spectroscopy. Solvent effects have been explicitly considered by modeling the nonradiative interaction with the solute as a random variable. To formulate a solution, it is necessary to introduce stochastic considerations. We assume that system–solvent interactions induce random shifts in the Bohr frequency of the adiabatic states, and their manifestation corresponds to the broadening of the upper level. The Born–Oppenheimer (BO) electronic energy curves for this molecular model consist of two intertwined harmonic oscillator potentials shifted in both their position and their minimum equilibrium energy. The critical quantities for this analysis are the transition and permanent dipole moments, which depend strongly on intramolecular coupling. Our results show how absorption and refractive index are affected by vibronic coupling and solvent stochasticity.","PeriodicalId":16520,"journal":{"name":"Journal of Nonlinear Optical Physics & Materials","volume":"382 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2021-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83448541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}