In this paper, the results of studying the structural and optical properties of individual GaP(111) nanowires (NWs) and their arrays by Raman spectroscopy and atomic force microscopy (AFM) were presented. The GaP NW arrays were grown on a Si(111) substrate by self-catalytic growth via the vapor–liquid–crystal mechanism. Individual NWs were mechanically transferred onto a gold surface. In the Raman spectra of GaP nanowires, the modes of transversal (TO), longitudinal (LO), and surface (SO) optical phonons were observed. Surface-enhanced Raman scattering by optical modes was revealed in GaP nanowires near the gallium droplet due to the localized surface plasmon resonance in the droplet. The Raman maps of GaP NWs were recorded in different scattering geometries. The Raman enhancement factor for GaP NWs of 104 and 60 nm in diameter attained ∼ 11 and 6, respectively.

Monolayer triangular WS2 and MoS2 islands grown by chemical vapor deposition was investigated by near-field photoluminescence (nano-PL) enhanced by the metallized atomic force microscope (AFM) tip. To achieve maximum near-field response from WS2 and MoS2 materials fabricated Au and Ag metallized AFM tips were used. Maximum nano-PL responds from the islands is observed under the resonant conditions when the energy of the localized surface plasmon of the metallized probe coincides with the energy of the exciton luminescence of the WS2 and MoS2 materials. Nano-PL mapping of the exciton response allows visualizing structural defects and determine the local thickness changes of monolayer islands with nanometer spatial resolution.

Monolayer triangular WS 2 and MoS 2 islands grown by chemical vapor deposition was investigated by near-field photoluminescence (nano-PL) enhanced by the metallized atomic force microscope (AFM) tip. To achieve maximum near-field response from WS 2 and MoS 2 materials fabricated Au and Ag metallized AFM tips were used. Maximum nano-PL responds from the islands is observed under the resonant conditions when the energy of the localized surface plasmon of the metallized probe coincides with the energy of the exciton luminescence of the WS 2 and MoS 2 materials. Nano-PL mapping of the exciton response allows visualizing structural defects and determine the local thickness changes of monolayer islands with nanometer spatial resolution.

Локальный спектральный анализ полупроводниковых структур для устройств фотоники возможен с помощью наноспектроскопии, включая нано-КРС (комбинационное рассеяние света) и нано-ФЛ (фотолюминисценцию).Эти методы представляют собой комбинацию атомно-силовой микроскопии (АСМ) и КРС, либо ФЛ и основаны на усилении оптического сигнала наноструктуры полем локализованного поверхностного плазмона металлического зонда АСМ микроскопа могут быть применены для изучения фононного и электронного спектров двумерных (2D), одномерных (1D) и нульмерных (0D) отдельных полупроводниковых наноструктур с пространственным разрешением ниже дифракционного предела.Представлены результаты исследования нано-КРС на оптических фононах нанокристаллов (НК) CdSe и AlN наноколонн AlN и пленок графена и мультиграфена, помещенных на плазмонные подложки и нано-ФЛ нанокристаллов GaAs и двумерных островков дихалькогенидов металлов (MoS2 и WS2).В диапазоне частот оптических фононов выполнено нано-КРС коллоидных нанопластинок CdSe/CdS, сформированных по типу ядро/оболочка, монослоев MoS2, помещенные в зазоре между металлизированным (Au, Ag) острием АСМ микроскопа и плазмонной подложкой, определены размеры и форма наноструктур, структурные дефекты и возникающие в них механические напряжения.Обсуждается различие нано-КРС от НК CdSe на отдельном нанодиске золота, записанное при различных длинах волн возбуждения.Нано-КРС на частотах поверхностных оптических (SO) фононов наблюдалось от отдельных наноколонн AlN (1D), помещенных на поверхность Au, и НК AlN (0D), выращенных с помощью молекулярно-лучевой эпитаксии на Si, и.Нано-КРС изображение отдельного НК AlN размером около 250 нм с кристаллической структурой вюрцита демонстрирует его гексагональную форму.Обсуждаются различия в нано-КРС изображениях наноколонн AlN, записанных при различной поляризации света.Нано-ФЛ от монослойных островков MoS2 и WS2, выращенных кремниевой подложке, демонстрируют локальное изменение энергии и интенсивности экситонной ФЛ в зависимости от числа монослоев и наличия структурных дефектов.Обнаружено усиление непрямозонной нано-ФЛ в нанокристаллах GaAs, что позволило выполнить нано-ФЛ картирование отдельного нанокристалла.Исследование поддержано Российским Научным Фондом (грант №22-12-00302).

In this work, the phonon spectra of atomically thin ZnSenanoplatelets(NPLs) were studied using Raman and infrared spectroscopies. Atomicallythin ZnSe NPLs were grown on the Si substrate covered with a 100 nmthick gold layer by the colloidal method in the temperature rangeof 100-170 & DEG;C. The triangular and rectangular NPLs with2.5- and 4-monolayer thicknesses, respectively, were synthesized,as determined by atomic force microscopy (AFM) measurements. Longitudinaloptical (LO) and transverse optical (TO) phonon modes in ZnSe NPLswere found at 198 and 252 cm(-1), respectively, andthe surface optical phonon mode was observed at about 216 cm(-1). The LO and TO phonon modes revealed the opposite frequency shiftswith increasing growth temperature. The effect was induced by thephonon confinement, and it confirmed the formation of NPLs of differentthicknesses. Comparing the frequency positions of longitudinal andTO phonon modes confined in ZnSe NPLs with the data on the dispersionof optical phonons in bulk ZnSe, the thickness of the NPLs formedat a low temperature was derived as 0.567 nm, correlating well withthe AFM results.

Resonance reflection of light from the ordered arrays of silicon nanopillars (Si NP) was investigated. The height of Si NP was 450 nm. The effect of Si NP oxidation in concentrated nitric acid on the position of resonances in reflection spectra was studied. A weak influence of the additional polymeric coating on the characteristics of reflection from the structures was proven. It is established on the basis of the results of experimental investigation and direct numerical modeling by means of three-dimensional finite difference time domain algorithm (3D FDTD) that the dependence of the resonant wavelength for Si NP on the diameter of Si NP is a linear function with nonzero displacement depending on the pitch.

Resonance reflection of light from the ordered arrays of silicon nanopillars (Si NP) was investigated. The height of Si NP was 450 nm. The effect of Si NP oxidation in concentrated nitric acid on the position of resonances in reflection spectra was studied. A weak influence of the additional polymeric coating on the characteristics of reflection from the structures was proven. It is established on the basis of the results of experimental investigation and direct numerical modeling by means of three-dimensional finite difference time domain algorithm (3D FDTD) that the dependence of the resonant wavelength for Si NP on the diameter of Si NP is a linear function with nonzero displacement depending on the pitch. Keywords: silicon nanopillars, structural colors, all-dielectric nanophotonics.

In this work, approaches for fabrication metal coated probes for Tip Enhanced Raman Spectroscopy (TERS) are considered. It was proposed to use optical characterization of probes to achieve the effective TERS of semiconductor nanoobjects. The shape and size of the metal cluster at the tip apex determines the position of the localized surface plasmon resonance, the electromagnetic field enhancement and, thus, TERS performance. The possibility of optimizing the characteristics of the probes for TERS studies of nanoobjects has been investigated.

В данной работе исследовался фононный спектр нанопластинок ZnSe разной толщины, синтезированных методом коллоидной химии. Для определения структурных параметров нанопластинок ZnSe использовалась просвечивающая электронная микроскопия. Нанопластинки ZnSe наносились капанием на Si подложку, покрытую тонким слоем (100 нм) золота. Затем проводился термический отжиг полученных образцов при Т=140ºС для удаления органики. Для измерения ИК спектров использовался ИК Фурье спектрометр Vertex 80v. ИК измерения проводились при нормальном и наклонном (75º) падении. Измерение спектров КРС проводилось с помощью спектрометра Horiba XploRa Plus в геометрии обратного рассеяния при комнатной температуре, длины волн возбуждения составляли 532 и 638 нм.

The sublimation and van der Waals (vdW) epitaxy on Bi2Se3(0001) surface have been first visualized using in situ reflection electron microscopy. When Bi2Se3(0001) surface was exposed to a Se molecular beam (up to 0.1 nm/s) and heated to ∼400°C, we observed ascending motion of atomic steps corresponding to congruent Bi2Se3 sublimation. During the sublimation, grooves made by probe lithography act as sources of atomic steps: groove depth increases and generates atomic steps that move in the ascending direction away from the source. We used this phenomenon to create self-organized regularly-spaced zigzag atomic steps having 1 nm height on the Bi2Se3(0001) surface. The deposition of Bi (up to ∼0.01 nm/s) onto the Bi2Se3(0001) surface at constant Se flux (up to ∼0.1 nm/s) reversed the direction of the step flow, and vdW epitaxy was observed. The deposition of In and Se onto the Bi2Se3(0001) surface at ∼400°C led to the epitaxial growth of layered In2Se3. This vdW heteroepitaxy started with 2D island nucleation and, after 3–5 nm growth, continued with a screw-dislocation-driven formation of 3D islands. Ex situ Raman scattering measurements have shown that the grown 20-nm-thick In2Se3 film exhibits vibrational modes that originate from the β-In2Se3 crystal phase.

Сообщается об обнаружении комбинационного рассеяния света (КРС) двумерными, одномерными и нульмерными полупроводниковыми наноструктурами, усиленного металлизированным зондом атомного-силового микроскопа (АСМ). При нанесении наноструктур на поверхность массивов золотых нанодисков обнаружено гигантское усиление сигнала КРС при нанометровом пространственном разрешении (нано-КРС).

Silicon nanopillar (Si NP) arrays with the axial p-n junction were formed and investigated. A method to fabricate Si NP ordered arrays by means of electron beam lithography using the negative electron resist and reactive ion etching is presented.

Abstract —The results of investigating the spectral characteristics of reflection from silicon nanopillar (Si NP) microarrays in the wavelength region from 400 to 1100 nm are presented. The Si nanopillars are formed by electron lithography on a negative resist with subsequent reactive ion etching. The Si nanopillars are etched through a resist mask and SiO_2 100 nm thick. In the spectra of reflection from nanopillar microarrays, minima are observed, the position of which depends strongly on the Si nanopillar diameter.

The results of investigating the spectral characteristics of reflection from silicon nanopillar (Si NP) microarrays in the wavelength region from 400 to 1100 nm are presented. The Si nanopillars are formed by electron lithography on a negative resist with subsequent reactive ion etching. The Si nanopillars are etched through a resist mask and SiO2 100 nm thick. In the spectra of reflection from nanopillar microarrays, minima are observed, the position of which depends strongly on the Si nanopillar diameter.

Проведено исследование спектральных характеристик отражения оптического излучения микромассивами кремниевых нанопилларов в видимом и ближнем ИК диапазоне.Микромассивы кремниевых нанопилларов формируются посредством электронно-лучевой литографии и реактивного ионного травления.Измерены спектры отражения микромассивов с периодом нанопилларов в

The optical-reflection spectra of microarrays of silicon nanopillars are studied in the visible and near-IR regions. The microarrays of silicon nanopillars are formed by electron-beam lithography and reactive ion etching. The reflection spectra of nanopillar arrays with pitches of 400, 600, 800, and 1000 nm are measured. The height of nanopillars in the array is 0.5 μm, and the diameter varies from 150 to 240 nm. It is noted that the spectral features of the reflection are caused by increased absorption of individual nanopillars and interference effects inside the array. A relation between the geometric parameters of nanopillars and the resonance reflection characteristics is determined taking into account the influence of the substrate.

In this paper, the formation of the arrays of silicon nanopillars by means of electron-beam lithography and dry etching is described. Silicon nanopillars 50 to 350 nm in diameter, 80 to 800 nm high were fabricated. Important features of the formation of these structures were described. Cones and tapered cones can be formed with the help of this method.