bluuebunny/crossref_metadata_2025_split huggingface dataset:
Strain tunable intrinsic ferromagnetic in 2D square CrBr2
Authors: Li Fei , Ren Yulu , Wan Wenhui , Liu Yong , Ge Yanfeng 
Published: November 2021

Two-dimensional intrinsic magnetic materials with high Curie temperature (Tc) coexisting with 100% spin polarization are highly desirable for realizing promising spintronic devices. In the present work, the intrinsic magnetism of monolayer square CrBr2 is predicted by using first-principles calculations. The monolayer CrBr2 is an intrinsic ferromagnetic half-metal with the half-metallic gap of 1.58 eV. Monte Carlo simulations based on the Heisenberg model estimate Tc as 212 K. Furthermore, the large compressive strain makes CrBr2 undergo ferromagnetic–antiferromagnetic phase transition when the biaxial tensile strain larger than 9.3% leads to the emergence of semiconducting electronic structures. Our results show that the intrinsic half-metal with a high Tc and controllable magnetic properties endow monolayer square CrBr2 as a potential material for spintronic applications.
Focusing grating couplers for radio-frequency surface ion traps
Authors: Abbasov Timur , Kazakov Ivan , Sherstov Ivan , Kontorov Sergey , Shipulin Arkadi , Kueppers Franko , Lakhmanskiy Kirill 
Published: November 2021

Abstract
We present a photonic integrated circuit design with multiple focusing grating couplers that can be used in a surface ion trap. This system allows transferring laser radiation from different laser sources to the ion trapped 240 μm above the surface for further manipulations.
Chiral light in single-handed Fabry-Perot resonators
Authors: Taradin Alexey , Baranov Denis G. 
Published: November 2021

Abstract
Chirality is a universal phenomenon that is encountered on many different length scales in nature. Interaction of chiral matter with chiral light results in the effect of circular dichroism, which underlies many techniques of discriminating molecular enantiomers. Enhancing dichroic effects is typically achieved by interfacing chiral matter with various optical resonators. In this context it is important to understand how the eigenmodes of optical cavities relate to the field states with well-defined handedness. Here, we present the model of a single-handedness chiral optical cavity supporting only an eigenmode of a given handedness without the presence of modes of other helicity. Resonant excitation of the cavity with light of appropriate handedness enables formation of a helical standing wave with a uniform chirality density, while the opposite handedness does not cause any resonant effects. Our findings expand the set of tools for investigations of chiral matter and open the door towards studies of chiral electromagnetic vacuum states.
Multi wall carbon nanotubes as a top electrode for perovskite light-emitting electrochemical cells
Authors: Bodyago Elena , Gets Dmitry , Baeva Maria , Mukhin Ivan , Makarov Sergei , Zakhidov Anvar 
Published: November 2021

Abstract
Carbon nanotubes are promising materials for use as flexible and transparent electrodes for a wide variety of optoelectronic devices like solar cells and light-emitting diodes. Moreover, the chemical inertness of carbon nanotubes matches with the operation of light-emitting electrochemical cells where ion migration is a main working principle especially based on halide perovskite, in which ions corrode metal electrodes. Here we demonstrate how the removal of synthesis residuals via synthesis enables the use of multiwall carbon nanotubes as a transparent electrode.
Optical properties of new hybrid nanoantenna in submicron cavity
Authors: Gritsienko A V , Kurochkin N S , Lega P V , Orlov A P , Ilin A S , Eliseev S P , Vitukhnovsky A G 
Published: November 2021

Abstract
An essential area of nanophotonics is the creation of efficient quantum emitters operating at high frequencies. In this regard, plasmon nanoantennas based on nanoparticles on metal (nanopatch antennas) are incredibly relevant. We have created and investigated a new hybrid nanoantenna with a cube on metal and quantum emitters. We demonstrate an increase up to 60 times for the rate of spontaneous emission and the gap-plasmon mode changing for nanopatch antenna in the metallic well. The results show the possibility of creating plasmon antennas in a controlled way by creating an array of regularly arranged nanoscale cavities-resonators.
Broadband metasurfaces loaded with non-Foster elements
Authors: Kalmykov Nikita , Buiantuev Bair , Kholodnyak Dmitry 
Published: November 2021

Abstract
Metasurfaces have been widely used to design low-profile antennas, thin absorbers, lenses etc. The operational frequency band of a metasurface is rather narrow due to its resonant nature. Loading metasurface unit cells with non-Foster elements allows for remarkable bandwidth extension. In this paper, design of a broadband metasurface to operate as an artificial magnetic conductor is considered. The main issues which influence the bandwidth extension such as implementation of the non-Foster load, minimization of conversion error of a negative impedance converter, and circuit stabilization are addressed.
Floquet engineering of carbon nanotubes
Authors: Kibis O. V. , Boev M. V. , Kovalev V. M. 
Published: November 2021

Abstract
The Floquet theory for electrons in carbon nanotubes (CNTs) irradiated by a circularly polarized electromagnetic wave propagating along the CNT axis is developed. It is demonstrated, particularly, that the irradiation opens the gap between the conduction and valence bands of CNTs of metal type and lifts the degeneracy of electron states with mutually opposite angular momenta along the CNT axis. As a consequence, the optically-induced metal-insulator transition and the optical Zeeman effect appear in the CNTs. It follows from the theory that these light-induced phenomena can be observed in the modern experiments.
Second-harmonic generation enhancement in high-contrast micropillar AlGaAs resonator in bound states in the continuum regime
Authors: Kolodny Stanislav , Kozin Valerii , Iorsh Ivan 
Published: November 2021

Abstract
It has been shown that the use of micropillar resonators, which comprise a cylindrical semiconductor cavity sandwiched between the Bragg mirrors can substantially increase the quality factor preserving the mode volume, and thus substantially enhance the local fields. Here, we show that these structures indeed can facilitate the significant enhancement of the SHG efficiency. We provide a specific design of the AlGaAs pillar microcavity and use the numerical modelling to directly show the resonant enhancement of the SHG efficiency. We believe that the presented results would be of high interest to the nanophotonic community, especially in nonlinear optics field.
Silicon nanowires as multi—environment sensor elements for carbon monoxide and ammonia detection
Authors: Kondratev V. M. , Morozov I.A. , Vyacheslavova E.A. , Gudovskikh A. S. , Nalimova S. S. , Moshnikov V.A. , Bolshakov A. D. 
Published: November 2021

Abstract
Carbon monoxide and ammonia are inorganic agents found both in nature and in the human body, which is of great interest for modern sensing. First, in concentrations of the order of 1 ppm agents are produced by human and can be markers of changes in human health. Second, at concentrations of the order of 100 ppm, carbon monoxide and ammonia are toxic and hazardous. This work is aimed at fabrication and study of precise, technological and relatively cheap sensors compatible with a gas and liquid medium for CO and NH3 detection, respectively.
Probing guided monolayer semiconductor polaritons below the light line
Authors: Kondratyev V. , Permyakov D. , Kravtsov V. , Krizhanovskii D. N. , Samusev A. K. 
Published: November 2021

Abstract
In this work, we demonstrate an approach to study exciton-polaritons supported by transition metal dichalcogenide monolayers coupled to an unstructured planar waveguide below the light line. In order to excite and probe such waves propagating along the interface with the evanescent fields exponentially decaying away from the guiding layer, we employ a hemispherical ZnSe solid immersion lens (SIL) precisely positioned in the vicinity of the sample. We visualize the dispersion of guided polaritons using back focal (Fourier) plane imaging spectroscopy with the high-NA objective lens focus brought to the center of SIL. This results in the effective numerical aperture of the system exceeding an exceptional value of 2.2 in the visible range. In the experiment, we study guided polaritons supported by a WS2 monolayer transferred on top of a Ta2O5 plane-parallel optical waveguide. We confirm room-temperature strong light-matter coupling regime enhanced by ultra-low intrinsic ohmic and radiative losses of the waveguide. Note that in the experiment, total radiative losses can be broadly tuned by controlling SIL-to-sample distance. This gives a valuable degree of freedom for the study of polariton properties. Our approach lays the ground for future studies of light-matter interaction employing guided modes and surface waves.
Doubly excited states in a chiral waveguide-QED system: description and properties
Authors: Kornovan D. , Vlasiuk E. , Poddubny A. , Petrov M. 
Published: November 2021

Abstract
In modern quantum optics chiral waveguide quantum-electrodynamical (wQED) systems are attracting a lot of attention from the perspective of fundamental science, and possible interesting applications. In our work we theoretically analyze the eigenstates in a two-excitation domain of an ensemble of two-level atoms that are periodically spaced, and asymmetrically coupled to a guided mode. We found that in a regime when all atoms emit photons in-phase, most eigenstates in such a system can be well-approximated and described through the eigenstates from a single excitation domain, while the rest present a superposition of bound states with two strongly attracting excitations, and states, for which the excitations strongly repel from each other occupying the opposite edges of the system.
Bosonic Hofstadter butterflies in the presence of phonon modes
Authors: Krivosenko Yury , Iorsh Ivan , Shelykh Ivan 
Published: November 2021

Abstract
We have investigated the influence of lattice sites vibrations on bosonic Hofstadter’s butterfly (HB) spectrum for the case of conventional square lattice. Only the pair of specific phonon modes with opposite quasimomenta has been taken into account. The study has shown that HB-type spectra can be substantially modified by the presence of phonons, depending on the ratios of such parameters of the system as site-to-site transition amplitudes, particle-phonon interaction constant, and characteristic vibration frequency.
Non-Huygens transparent metasurfaces based on the novel Hybrid anapole state
Authors: Kuznetsov A V , Canós Valero A 
Published: November 2021

Abstract
In this work we studied the optical properties of the metasurfaces based on silicon nanocylinders experincing hybrid anapole. Our investigation shows the possibility of creating fully invisible metasurfaces consisting of silicon nanocylinders based on the novel state which in their properties can compete with the Huygens’ metasurfaces. These results can be used in various fields of nanophotonics and may have important outcome in the development of various photonic devices.
Up-conversion photoluminescence specificity of a hybrid sponge nanostructures
Authors: Larin Artem , Kurganov Egor , Bruyére Stephanie , Nominé Alexandre , Ageev Eduard , Samusev Anton , Zuev Dmitry 
Published: November 2021

Abstract
Over the past decades, silicon is proved to be as a promising material for the development of devices in the fields of nanophotonics and optoelectronics. However, the material so popular at the current time did not find its application in nanoscale radiation sources due to the indirect bandgap of the semiconductor, which leads to low quantum efficiency. This work represents experimental results on the features of the silicon up-conversion photoluminescence enhanced by the optical resonances of the plasmonic nanosponge. The internal configuration of the nanostructure was confirmed by scanning transmission electron microscopy. The optical characterisation was provided by the dark-field spectroscopy, up-conversion photoluminescence generation and life-time measurements. The such new nanostructure type is promising for the development of nanoscale sources of broadband radiation and other applications of silicon photonics.
Flat-band dark polaritons in two-dimensional chiral-waveguide quantum electrodynamics
Authors: Marques Y. , Shelykh I. A. , Iorsh I. V. 
Published: November 2021

Abstract
We consider a two-dimensional extension of the one-dimensional waveguide quantum electrodynamics and investigate the nature of linear excitations in two-dimensional arrays of qubits (particularly, semiconductor quantum dots) coupled to networks of chiral waveguides. We show that the combined effects of chirality and long-range photon mediated qubit-qubit interactions lead to the emergence of the two-dimensional flat bands in the polaritonic spectrum, corresponding to slow strongly correlated light.
Upconversion photoluminescence of perovskite nanoparticles encapsulated in porous sub-micron spheres supporting Mie resonances.
Authors: Masharin Mikhail , Peltek Oleksii , Talianov Pavel , Zelenkov Lev , Zuyzin Mikhail , Makarov Sergey 
Published: November 2021

Abstract
Currently, halide perovskites are very perspective materials not only for photovoltaics but also for nanophotonic and especially nonlinear optics. These materials have already demonstrated high two-, three- and many- photon absorption coefficients, strong Kerr-nonlinearity, and high-efficient second harmonic generation. Easy and cheap fabrication gives halide perovskites a wide area for scientific research and engineering applications. However, to achieve the stability of perovskites is still a challenging task, which scientific community is working on. In this work, we study a new form of encapsulation of perovskite nanoparticles in sub-micron porous dielectric nanospheres. Due to small pores in such spheres, perovskites are not only protected from external factors, but also are confined in size, which brings several features in the photoluminescence emission. We also show resonant properties of spherical sub-micron particles, which can be used for enhancing upconversion photoluminescence intensity.
Stability of bound states in the continuum in low-contrast photonic structures
Authors: Maslova E. E. , Bogdanov A.A. , Rybin M. V. , Sadrieva Z. F. 
Published: November 2021

Abstract
We consider quality (Q) factor of accidental bound states in the continuum in bilayer resonators consisting of low-index dielectric rods. The dependence of Q factor on the number of periods shows that Q factors increase with the increasing number of rods. We calculated the dependence of the resonator Q factor on the disorder by two methods: analytical (multiple scattering theory) and numerical (finite difference method) and showed that the results are in good agreement. Also, we investigated the dependence of the resonance frequency on disorder.
Creation of complex composites from Metal-Organic Frameworks with pure metal nanoparticles under electronic irradiation
Authors: Mezenov Yuri A. , Bruyere Stéphanie , Milichko Valentin A. 
Published: November 2021

Abstract
Metal-organic frameworks (MOFs) are unique materials with high porosity and flexibility utilized widely in chemistry and physics. However, they could be used as initial materials for creation new types of composites with nanoparticles. The creation of NPs inside MOFs crystals is related with different types of outer stimuli (temperature, light, and electron irradiation). Here we report about a new approach of the creation complex composites from MOFs’ crystals using the electron irradiation of the transmission electron microscope (TEM) as a highly precise method for the growing of different types of Ni and Cu nanoparticles and discuss about the dynamical process of NPs growth using the classical kinetic theory.
3D printed Ku band cylindrical Luneburg lens
Authors: Grigoriev I , Munina I , Zelenchuk D 
Published: November 2021

Abstract
The design of the cylindrical Luneburg lens manufactured by using 3D printing facilities was presented, fabricated and experimentally verified. The two different approaches to lens parameter discretization were applied to lens design and compared. The effective dielectric permittivity of Polylactic Acid (PLA) plastic samples with different infilling percentage were estimated by a resonant method.
Trapping-influenced photoluminescence intensity decay in semiconductor nanoplatelets
Authors: Kurilovich A A , Mantsevich V N , Stevenson K J , Chechkin A V , Palyulin V V 
Published: November 2021

Abstract
We present a diffusion-based simulation model for explanation of long time power-law decay of photoluminescence (PL) emission intensity in semiconductor nanoplatelets. In our model the shape of emission curves is an outcome of interplay of recombination, diffusion and trapping of excitons. At short times the excitons diffuse freely following the normal diffusion behaviour. The emission decay is purely exponential and is defined by recombination. At long times the transition into the subdiffusive motion happens and the emission occurs due to the release of excitons from surface traps. A power-law tail for intensity is a consequence of the release. The crossover from onelimit to another is controlled by diffusion properties. The approach reproduces the properties of experimental curves measured for different nanoplatelet systems.
Angular Goos-Hanchen shift in subwavelength gratings enhanced by surface plasmon resonance
Authors: Petrov N I , Danilov V A , Usievich B A 
Published: November 2021

Abstract
The angular Goos-Hanchen shift dependence on the subwavelength grating parameters and the incident Gaussian beam width is investigated theoretically. High sensitivity of the angular Goos-Hanchen shift to the incident angle of a light beam near the surface plasmon resonance is demonstrated. Splitting of the reflected beam into two angularly separated beams is shown for strongly focused beam incident at the surface plasmon resonance angle.
Theoretical study of surface states excitation in one-dimensional photonic crystal by halide perovskite microstructures
Authors: Popkova A.A. , Safronov K.R. , Markina D.I. , Pushkarev A. , Makarov S.V. , Bessonov V.O. , Fedyanin A.A. 
Published: November 2021

Abstract
In this work we develop the concept of integrated light source based on halide perovskite microwires for Bloch surface waves (BSWs) in one-dimensional photonic crystals. We theoretically study modes supported by a CsPbBr3 microwire placed on the surface of a photonic crystal. The modes with field distribution similar to BSW are observed. We study the coupling of microwire modes with BSWs depending on the geometric parameters of the wire. BSW excitation efficiency exceeding 40% is found for BSW-like modes of microwire. We also examine resonant modes of finite microwire and show that BSW-like modes play a main role in the excitation of BSWs with perovskite radiation. Our research paves the way for the implementation of complete integrated optical setups on the surface of photonic crystals.
Magneto-optical effects in second harmonic generation from W/Co/Pt nanofilms
Authors: Radovskaya V.V. , Mamonov E.A. , Pashen’kin I.Yu. , Gusev N.S. , Murzina T.V. 
Published: November 2021

Abstract
Interfaces between ferromagnetic metals and nonmagnetic specimen attract much attention as they are very important for the formation of magnetic properties of nanostructures. Vice versa, specific magnetic ordering at such interfaces may provide new effects in their optical and nonlinear optical response. In this work we study the magnetization-induced effects in optical second harmonic generation (SHG) in W/Co/Pt-based thin films with the thicknesses of the Co layer of 2 – 10 nm. Besides common odd in magnetization effects in the SHG intensity, we observe additional one that is not expected for homogeneously magnetized ferromagnetic films, which consists in modulation of p-polarized SHG intensity under longitudinal magnetic field application. The phenomenological description of the observed effect is performed in terms of gradient and second-order in magnetization contributions to the SHG polarization, where gradient of magnetization along the normal to the structure plays the key role.
Non-collinear ground state and stable bimerons from four-spin chiral interactions in D3h magnet
Authors: Rakhmanova G R , Osipov A N , Ilin D I , Shushakova I V , Iorsh I V 
Published: November 2021

Abstract
We demonstrate that four-spin interactions in crystals with D3h point group of symmetry can cause a phase transition from a collinear state to a non-collinear magnetic ground state (such as magnetic vortices or magnetic skyrmions), while all anti-symmetric chiral terms are forbidden by symmetry in such crystals. Moreover, D3h point group rather common among two dimensional magnets. Taking into account possible four-spin chiral exchange interactions is important for understanding noncollinear magnetic order in these systems. We also address a possible stabilization of bimerons by the same contribution.
Light propagation and interaction modelling in ring fibre nonlinear microcavities
Authors: Razukov V A , Melnikov L A 
Published: November 2021

Abstract
Usage of the ”Cabaret” explicit-implicit numerical scheme is proposed to model field dynamics both in microcavities and fibre cavities. Two opposite running waves are investigated with a number of the nonlinear effects included in the model, with potential to include more if necessary.
III-V nanowires with quantum dots: MBE growth and properties
Authors: Reznik R R , Kotlyar K P , Gridchin V O , Ilkiv I V , Khrebtov A I , Samsonenko Yu B , Soshnikov I P , Kryzhanovskaya N V , Leandro L , Akopian N , Cirlin G E 
Published: November 2021

Abstract
We demonstrate growth of AlGaAs NWs with GaAs QDs and InP NWs with InAsP QDs on silicon substrates. Results of GaAs QDs optical properties study have shown that these objects are sources of single photons. In case of InP NWs with InAsP QDs, the results showed that ~ 100% of homogeneously oriented NWs were formed with good optical quality of this system on a Si(111). PL spectrum peak near 1.3 μm indicates that such system is promising for optoelectronic devices.
Optical heating of doped semiconductor nanocylinders supporting quasi-BIC modes
Authors: Ryabov Daniil , Pashina Olesia , Zograf George , Makarov Sergey , Petrov Mihail 
Published: November 2021

Abstract
In the recent years, semiconductor and dielectric nanophotonic structures attracted a lot of attention for their resonant optical properties finding applications in thermal tuning and optical heating. Exciting high quality optical modes of both electric and magnetic nature in nanoresonators of high-index materials, one can effectively enhance optical absorption in such structures. Another big advantage of semiconductor materials is the ability to finely control the level of optical losses in visible and near infrared (near-IR) range through varying the doping level. In this work, we show theoretically that by moderate carrier doping of silicon via donors from group V materials one can achieve effective heating of nanoresonators. We show that by tuning the doping level of crystalline silicon supporting high quality non-radiative modes based on quasi bound states in the continuum one can achieve strong heating in near-IR under continuous wave regime illumination. We believe that our finding will pave the way for an efficient semiconductor near-IR all-optical sensors and nanoheaters.