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Writing with atoms： Oxygen adatoms on the MoO2/Mo（110） surface

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Nano Research 2013年第12期6卷 929-937页

作者： sergey A. Krasnikov Olaf Lubben Barry E. Murphy sergey I. Bozhko Alexander N. Chaika Natalia N. Sergeeva Brendan Bulfin and Igor v. Shvets Centre for Research on Adaptive Nanostructures and Nanodevices School of Physics Trinity College Dublin Dublin 2 Ireland Institute of Solid State Physics Russian Academy of Sciences Chernogolovka Moscow District 142432 Russia School of Chemistry University of Leeds Leeds LS2 9JT UK

Writing at the nanoscale using the desorption of oxygen adatoms from the oxygen-rich MoO2＋x/Mo（110） surface is demonstrated by scanning tunnelling microscopy （STM）. High-temperature oxidation of the Mo（110） surface results in a strained, bulk-like MOO2（010） ultra-thin film with an O-Mo-O trilayer structure. Due to the lattice mismatch between the Mo（110） and the MOO2（010）, the latter consists of well-ordered molybdenum oxide nanorows separated by 2.5 nm. The MoO2（010）/Mo（110） structure is confirmed by STM data and density functional theory calculations. Further oxidation results in the oxygen-rich MoOa^x/Mo（110） surface, which exhibits perfectly aligned double rows of oxygen adatoms, imaged by STM as bright protrusions. These adatoms can be removed from the surface by scanning （or pulsing） at positive sample biases greater than 1.5 v. Tip movement along the surface can be used for controlled lithography （or writing） at the nanoscale, with a minimum feature size of just 3 nm. By moving the STM tip in a predetermined fashion, information can be written and read by applying specific biases between the surface and the tip.

关键词： scanning tunnellingmicroscopy inelastic tunnelling atom manipulation molybdenum oxide

Direct patterning of reduced graphene oxide/graphene oxide memristive heterostructures by electron-beam irradiation

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Journal of Materials Science & Technology 2020年第3期38卷 237-243页

作者： Olesya O.Kapitanova Evgeny v.Emelin sergey G.Dorofeev Pavel v.Evdokimov Gennady N.Panin Youngmin Lee Sejoon Lee Lomonosov Moscow State University Leninskie gory119991 MoscowRussia Moscow Institute of Physics and Technology 9 Institutskiy per.DolgoprudnyMoscow Region141701Russia Institute of Microelectronics Technology and High-Purity Materials Russian Academy of SciencesChernogolovkaMoscow district142432Russia Nano Information Technology Academy Dongguk University-SeoulSeoul 04620Korea Quantum-Functional Semiconductor Research Center Dongguk University-SeoulSeoul 04620Korea Department of Semiconductor Science Dongguk University-SeoulSeoul 04620Korea

Memristive heterostructures,composed of reduced graphene oxide with different degree of reduction,were demonstrated through a simple method of‘direct electron-beam writing’on graphene *** with an electron beam at various doses and accelerating voltages made it possible to define highand low-conductivity graphene-oxide *** electron beam-reduced graphene oxide/graphene oxide heterostructure clearly exhibited a nonlinear behavior and a well-controlled resistive switching characteristic at a low operating-voltage range(v).The proposed memristive heterostructures are promising for highly-efficient digital storage and information process as well as for analogous neuromorphic computations.

关键词： Electron beam irradiation Reduced graphene oxide Graphene oxide Memristive heterostructure

Microperforation of the human nail plate by radiation of erbium lasers

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Frontiers of Optoelectronics 2017年第3期10卷 299-307页

作者： Andrey v. BELIKOv Andrey N. SERGEEv sergey N. SMIRNOv Anastasia D. TAvALINSKAYA Department of Laser Technologies and Systems Saint-Petersburg National Research University of Information Technologies Mechanics and Optics (ITMO University) Saint Petersburg 197101 Russia

The nail plate forms a barrier that limits the effectiveness of drug delivery in the treatment of nail diseases and prevents the outflow of fluid in the case of subungual hematoma formation. Microperforation of the nail plate through laser radiation can increase the effectiveness of drug delivery and ensure the possibility of blood outflow. This study detected and identified the type and threshold of effects that arise from exposing the nail plate to Yb,Er： Glass （λ = 1.54 μm） and Er：YLF （λ= 2.81 μm） laser radiation. The rate and efficiency of nail plate ablation by the radiation of these lasers were studied. The effect of the storage time of a freshly extracted nail plate in open air on its ablation rate by Er：YLF （ λ=2.81 μm） laser radiation was also investigated. The impact of the Yb,Er：Glass and Er：YLF laser pulses on the nail plate caused bleaching, carbonization, ablation with microcrater formation, and microperforation. The laser energy densities WE （thresholds） required for these effects were determined. The maximum ablation rate for Yb,Er：Glass laser radiation was 8 μm/pulse at WE = 91 ±2 J/cm2, whereas that for Er：YLF laser radiation was 12 μm/ pulse at WE= 10.5＋0.5 J/cm2. The maximum ablation efficiency for Yb,Er：Glass laser radiation was 0.1 μm/mJ at Ws = 10.5±0.5 J/cm2, whereas that for Er：YLF laser radiation was 4.6 μm/mJ at WE = 5.3±0.3 J/cm2. The laser ablation rate depends on the storage time and conditions of the freshly extracted nail plate. For example, when exposed to Er：YLF laser radiation, the laser ablation rate decreased by half from the initial maximum value in 96 h of air storage and returned to the initial value after 1 h of storage in distilled water.

关键词： Yb Er:Glass laser Er:YLF laser nail plate microperforation ablation rate ablation efficiency dehydration

Sinterability of nanopowders of terbia solid solutions with scandia,yttria,and lutetia

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Journal of Advanced Ceramics 2018年第4期7卷 362-369页

作者： Stanislav S.BALABANOv Dmitry А.PERMIN Elena Ye.ROSTOKINA sergey v.EGOROv ANDrey A.SOROKIN G.G.Devyatykh Institute of Chemistry of High-Purity Substances RAS Federal Research Center the Institute of Applied Physics RAS

The synthesis of nanopowders of terbia compounds with scandia, yttria, and lutetia was carried out using a self-propagating high-temperature synthesis method involving a mixture of nitrates of metals and glycine as a precursor. The nanopowder phase transformations were investigated using X-ray diffraction analysis. It was found that lutetia has a negligible effect on the phase formation in terbia. On the other hand, yttrium and scandium ions significantly suppressed crystallization. The densification kinetics of nanopowders of the Tb_2O_3 compounds and the microstructure of ceramics after microwave sintering were studied using dilatometry and scanning electron microscopy. The introduction of scandia, yttria, or lutetia contributed to the intensification of the densification of the terbia ceramics when heated in a microwave field. Near full-density materials of terbia solid solutions with lutetia and yttria were obtained at about 1600–1640 ℃. The ceramics of scandia–terbia compounds contained the second phase, which causes light scattering.

关键词： terbia microwave sintering X-ray analysis ceramics

Fe Nanoclusters on the Ge（001） Surface Studied by Scanning Tunneling Microscopy, Density Functional Theory Calculations and X-Ray Magnetic Circular Dichroism

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Nano Research 2011年第10期4卷 971-978页

作者： Olaf LUbben sergey A. Krasnikov Alexei B. Preobrajenski Barry E. Murphy Igor v. Shvets Centre for Research on Adaptive Nanostructures and Nanodevices （CRANN） School of Physics Trinity College Dublin Dublin 2 Ireland MAX-lab Lund University Box 118. 22100 Lund Sweden

Ge (001 ) 表面上的 Fe nanoclusters 的生长用低温度的扫描通道显微镜学(STM ) 和密度被学习了功能的理论(DFT ) 计算。STM 结果显示 Fe 在 Ge (001 ) 表面上起核心作用，形成一致尺寸的秩序井然的 nanoclusters。取决于准备条件， nan... 详细信息

Ge (001 ) 表面上的 Fe nanoclusters 的生长用低温度的扫描通道显微镜学(STM ) 和密度被学习了功能的理论(DFT ) 计算。STM 结果显示 Fe 在 Ge (001 ) 表面上起核心作用，形成一致尺寸的秩序井然的 nanoclusters。取决于准备条件， nanoclusters 的二种类型被观察在 nanocluster 以内有四或十六个 Fe 原子。结果被 DFT 计算证实。退火在 420 K 的 nanoclusters 导致 nanorow 结构的形成，由于在如此的温度的簇活动性。在 Ge (001 ) 表面上形成的 Fe nanoclusters 和 nanorow 结构显示出由 X 光检查磁性的圆形的二色性测量了的 superparamagnetic 行为。

关键词：扫描隧道显微镜 DFT计算密度泛函理论纳米团簇磁性圆二色 X射线铁团簇表面

Numerical method for axial motion artifact correction in retinal spectral-domain optical coherence tomography

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Frontiers of Optoelectronics 2020年第4期13卷 393-401页

作者： sergey Yu.KSENOFONTOv Pavel A.SHILYAGIN Dmitry A.TERPELOv valentin M.GELIKONOv Grigory v.GELIKONOv BioMedTech Lie Nizhny Novgorod 603155Russia Institute of Applied Physics of the Russian Academy of Science Nizhny Novgorod 603950Russia

A numerical method that compensates image distortions caused by random fluctuations of the distance to an object in spectral-domain optical coherence tomography(SD OCT)has been proposed and verified *** proposed method is based on the analysis of the phase shifts between adjacent scans that are caused by micrometer-scale displacements and the subsequent compensation for the displacements through phase-frequency correction in the spectral *** efficiency of the method is demonstrated in model experiments with harmonic and random movements of a scattering object as well as during in vivo imaging of the retina of the human eye.

关键词： optical coherence tomography(OCT) motion artifact correction retinal imaging numerical method

Genetic structure of the Amur tiger(Panthera tigris altaica)population:Are tigers in Sikhote-Alin and southwest Primorye truly isolated?

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Integrative Zoology 2016年第1期11卷 25-32页

作者： Pavel A.SOROKIN vyatcheslav v.ROZHNOv Anna U.KRASNENKO victor S.LUKAREvSKIY sergey v.NAIDENKO Jose A.HERNANDEZ-BLANCO A.N.Severtsov Institute of Ecology and Evolution Russian Academy of SciencesMoscowRussia

We used molecular genetic analyses to noninvasively identify individual Amur tigers and define subpopulations of tigers in the Russian Far *** identified 63 individuals after genotyping 256 feces,7 hair and 11 blood samples collected within southern,central and northern Sikhote-Alin,as well as Southwest *** of nuclear DNA at 9 microsatellite loci demonstrated greater genetic similarity between animals from southern and northern Sikhote-Alin(some 500 km apart)than between animals from Ussuriskii State Nature Reserve and Southwest Primorye(less than 10 km apart at their nearest point),suggesting that a true barrier exists preventing movements of tigers between Southwest Primorye and the southern Sikhote-Alin Mountains.

关键词： Amur tiger fecal DNA noninvasive genetic sampling Panthera tigris altaica

Effect of fluence and ambient environment on the surface and structural modification of femtosecond laser irradiated Ti

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Chinese Physics B 2016年第1期25卷 789-795页

作者： Umm-i-Kalsoom Shazia Bashir Nisar Ali M Shahid Rafique Wolfgang Husinsky Chandra S R Nathala sergey v Makarov Narjis Begum Institute for Applied Physics Vienna University of TechnologyViennaAustria Centre for Advanced Studies in Physics GC University LahorePakistan Department of Physics The University of LahorePala'stan Department of Basic Sciences and Humanities University of Engineering and Technology FasalabadPakistan Department of Physics University of Engineering and Technology LahorePakistan P.N.Lebedev Physics Institute RAS MoscowRussia Department of Physics COMSATS Institute of Information and TechnologyIslamabadPakistan

Under certain conditions, ultrafast pulsed laser interaction with matter leads to the formation of self-organized conical as well as periodic surface structures （commonly reffered to as, laser induced periodic surface structures, LIPSS）. The purpose of the present investigations is to explore the effect of fsec laser fluence and ambient environments （vacuum ＆ 02） on the formation of LIPSS and conical structures on the Ti surface. The surface morphology was investigated by scanning electron microscope （SEM）. The ablation threshold with single and multiple （N = 100） shots and the existence of an incubation effect was demonstrated by SEM investigations for both the vacuum and the 02 environment. The phase analysis and chemical composition of the exposed targets were performed by x-ray diffraction （XRD） and energy dispersive x-ray spectroscopy （EDS）, respectively. SEM investigations reveal the formation of LIPSS （nano ＆ micro）. FFT d-spacing calculations illustrate the dependence of periodicity on the fluence and ambient environment. The periodicity of nano-scale LIPSS is higher in the case of irradiation under vacuum conditions as compared to 02. Furthermore, the 02 environment reduces the ablation threshold. XRD data reveal that for the 02 environment, new phases （oxides of Ti） are formed. EDS analysis exhibits that after irradiation under vacuum conditions, the percentage of impurity element （A1） is reduced. The irradiation in the 02 environment results in 15% atomic diffusion of oxygen.

关键词： LIPSS ablation threshold incubation coefficient structural modification

Medium chromatic dispersion spectral-domain optical calculation and correction in coherence tomography

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Frontiers of Optoelectronics 2017年第3期10卷 323-328页

作者： vasily A. MATKIvSKY Alexander A. MOISEEv sergey Yu. KSENOFONTOv Irina v. KASATKINA Grigory v. GELIKONOv Dmitry v. SHABANOv Pavel A. SHILYAGIN valentine M. GELIKONOv Institute of Applied Physics Russian Academy of Sciences Nizhny Novgorod 603950 Russia

A method for determining and correcting distortions in spectral-domain optical coherence tomography images caused by medium dispersion was developed. The method is based on analysis of the phase distribution of the interference signal recorded by an optical coherence tomography device using an iterative approach to find and compensate for the effect of a medium＇s chromatic dispersion on point-spread function broadening in optical coherence tomography. This enables compensation of the impact of medium dispersion to an accuracy of a fraction of a radian （units of percent） while avoiding additional measurements and solution of the optimization problem. The robustness of the method was demonstrated experimentally using model and biological objects.

关键词： optical coherence tomography (OCT) dispersion image resolution restoration