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Quantum information and microscopic measuring instruments

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Communications in Theoretical Physics 2020年第1期72卷 44-51页

作者： alexey v Melkikh Ural Federal University YekaterinburgRussia

The consideration of measuring instruments as macroscopic bodies leads to neglect of the microscopic processes that occur during *** disregard is not justified in general *** an example of measurements using microscopic instruments,the scattering of a photon by an electron with electron interference at two slits(Compton effect)was *** amount of information that can be obtained in such a process is inversely proportional to the wavelength of the incident *** large photon wavelengths(soft measurements),the pure state of the electron can be disrupted by an arbitrarily small extent;accordingly,the amount of information extracted in such an experiment is also arbitrarily *** is shown that the energy price for a bit obtained in such a measurement tends toward a constant value for increasing the photon *** instruments can be used in situations where energy costs for measurements are important.

关键词： measurement problem double-slit experiment von Neumann entropy decoherence compton effect

Nonlinearity of Quantum Mechanics and Solution of the Problem of Wave Function Collapse

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Communications in Theoretical Physics 2015年第7期64卷 47-53页

作者： alexey v.Melkikh Ural Federal University

The problem of the wave function collapse(a problem of measurement in quantum mechanics) is *** is shown that it can be solved based on quantum mechanics and does not require any additional assumptions or new theories. The particle creation and annihilation processes, which are described based on quantum field theory, play a key role in the measurement processes. Superposition principle is not valid for the system of equations of quantum field theory for particles and fields, because this system is a non-linear. As a result of the creation(annihilation) of a particle,an additional uncertainty arises, which "smears" the interference pattern. The imposition of such a large number of uncertainties in the repetitive measurements leads to the classical behavior of particles. The decoherence theory also implies the creation and annihilation of particles, and this processes are the consequence of non-linearity of quantum mechanics. In this case, the term "collapse of the wave function" becomes a consequence of the other statements of quantum mechanics instead of a separate postulate of quantum mechanics.

关键词： creation and annihilation of particles decoherence

Nanoscopic imaging of oxidized graphene monolayer using tip-enhanced Raman scattering.

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Nano Research 2018年第12期11卷 6346-6359页

作者： Joseph M.Smolsky alexey v.Krasnoslobodtsev Department of Physics University of Nebraska at Omaha6001Dodge StreetOmaha NE 68182USA

Tip-enhanced Raman scattering (TERS) can be used for the structural and chemical characterization of materials with a nanoscale resolution, and offers numerous advantages compared to other forms of imaging. We use TERS to track the local structural features of a CvD-grown graphene monolayer. Ag nanoparticles were added to AFM probes using ion-beam sputtering in order to make them TERS-active. Such modification provides probes with large factors of enhancement and good reproducibility. TERS measurements on graphene show an emergence of a defect-induced D-Raman band and a strain-induced shoulder of the graphene’s G-band. Comparison of TERS results with micro-Raman for oxidized graphene suggests that local oxidation occurs with the introduction of sp3 defects, under TERS conditions.

关键词： graphene Raman spectroscopy tip-enhanced Raman scattering graphene oxidation

A simple semiempirical model for the static polarizability of electronically excited atoms and molecules

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Chinese Physics B 2023年第4期32卷 290-301页

作者： Alexander S Sharipov alexey v Pelevkin Boris I Loukhovitski Central Institute of Aviation Motors Aviamotornaya 2Moscow 111116Russia

We present a semiempirical analytical model for the static polarizability of electronically excited atoms and molecules,which requires very few readily accessible input data,including the ground-state polarizability,elemental composition,ionization potential,and spin multiplicities of excited and ground *** very simple model formulated in a semiclassical framework is based on a number of observed trends in polarizability of electronically excited *** adjust the model,both accurate theoretical predictions and reliable measurements previously reported elsewhere for a broad range of multielectron species in the gas phase are *** some representative compounds of general concern that have not yet attracted sufficient research interest,the results of our multireference second-order perturbation theory calculations are additionally *** show that the model we developed has reasonable(given the considerable uncertainties in the reference data)accuracy in predicting the static polarizability of electronically excited species of arbitrary size and excitation *** findings can be useful for many applications,where there is a need for inexpensive and quick assessments of the static gas-phase polarizability of excited electronic states,in particular,when building the complex nonequilibrium kinetic models to describe the observed optical refractivity(dielectric permittivity)of nonthermal reacting gas flows.

关键词： polarizability electronic excitation semiempirical model quantum chemistry

Tuning the chemiluminescence of a luminol flow using plasmonic nanoparticles

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Light(Science & Applications) 2016年第1期5卷 430-436页

作者： Alina Karabchevsky Ali Mosayyebi alexey v Kavokin Electrooptical Engineering Unit and Ilse Katz Institute for Nanoscale Science&Technology Ben-Gurion UniversityBeer-Sheva 84105Israel Engineering Sciences Unit Engineering and the EnvironmentUniversity of SouthamptonSouthampton SO171BJUK Department of Physics and Astronomy University of SouthamptonSouthampton SO171BJUK CNR-SPIN Viale del Politecnico 1I-00133 RomeItaly

We have discovered a strong increase in the intensity of the chemiluminescence of a luminol flow and a dramatic modification of its spectral shape in the presence of metallic *** observed that pumping gold and silver nanoparticles into a microfluidic device fabricated in polydimethylsiloxane prolongs the glow time of *** have demonstrated that the intensity of chemiluminescence in the presence of nanospheres depends on the position along the microfluidic serpentine *** show that the enhancement factors can be controlled by the nanoparticle size and ***,the emission peak of luminol overlaps with the absorption band of the nanospheres,which maximizes the effect of confined plasmons on the optical density of states in the vicinity of the luminol emission *** observations,interpreted in terms of the Purcell effect mediated by nano-plasmons,form an essential step toward the development of microfluidic chips with gain *** implementation of the discovered effect will include improving the detection limits of chemiluminescence for forensic science,research in biology and chemistry,and a number of commercial applications.

关键词： chemiluminescence microfluidics nanoparticles plasmonics

Asymmetry ratio as a parameter of Eu^3＋ local environment in phosphors

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Journal of Rare Earths 2018年第5期36卷 474-481页

作者： Ilya E. Kolesnikov alexey v. Povolotskiy Daria v. Mamonova Evgeny Yu. Kolesnikov alexey v. Kurochkin Erkki Lahderanta Mikhail D. Mikhailov Saint Petersburg State University 7/9 Universitetskaya nab. 199034 St.petersburg.Russia Lappeenranta University of Technology LUT Skinnarilankatu 34 53850 Lappeenranta Finland Scientific and Technological Institute of Optical Material Science VNTs S. I. Vavilov State Optical Institute Babushkina 36-1 192171 St. Petersburg Russia volga State University of Technology Lenin Sq. 3 424000 Yoshkar-Ola Russia

Study of the local environment of certain ion is quite a complex problem. Due to the unique luminescent properties, Eu^3＋ ions can be used as a structural probe. In this paper, effect of doping concentration,excitation wavelength and excitation mechanism on asymmetry ratio was systematically studied using Y3Al5O12：Eu^3＋, YvO4：Eu^3＋ and Y2O3：Eu^3＋nanophosphors. The asymmetry ratio gives information about the local surrounding and environmental changes around the Eu^3＋ ions. Asymmetry ratios of YAG：Eu^3＋and YvO4：Eu^3＋ nanopowders were calculated using standard technique and the obtained average values were found to be 0.75 and 8.2, respectively. However, it is found that standard method of asymmetry ratio calculation is suitable only for samples where all Eu^3＋ ions occupy one site. The ＂multisite model＂ of asymmetry ratio calculation was developed and used for Y2O3：Eu^3＋ nanocrystalline powders. Average value of asymmetry ratio for Eu^3＋ ions occupied ＂normal＂ sites is 6.0 and for Eu^3＋ ions occupied ＂defect＂sites is 2.3.

关键词： Eu3+ Oxide powders Luminescence Asymmetry ratio Structural probe Rare earths

Effects of subsampling on characteristics of RNA-seq data from triple-negative breast cancer patients

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Chinese Journal of Cancer 2015年第10期34卷 427-438页

作者： alexey Stupnikov Galina v Glazko Frank Emmert-Streib Computational Biology and Machine Learning Laboratory Faculty of MedicineHealth and Life SciencesSchool of MedicineDentistry and Biomedical SciencesCenter for Cancer Research and Cell BiologyQueen's University Belfast Division of Biomedical Informatics University of Arkansas for Medical Sciences Computational Medicine and Statistical Learning Laboratory Department of Signal ProcessingTampere University of Technology

Background:Data from RNA-seq experiments provide a wealth of information about the transcriptome of an ***,the analysis of such data is very *** this study,we aimed to establish robust analysis procedures that can be used in clinical ***:We studied RNA-seq data from triple-negative breast cancer ***,we investigated the subsampling of RNA-seq ***:The main results of our investigations are as follows:(1) the subsampling of RNA-seq data gave biologically realistic simulations of sequencing experiments with smaller sequencing depth but not direct scaling of count matrices;(2) the saturation of results required an average sequencing depth larger than 32 million reads and an individual sequencing depth larger than 46 million reads;and(3) for an abrogated feature selection,higher moments of the distribution of all expressed genes had a higher sensitivity for signal detection than the corresponding mean ***:Our results reveal important characteristics of RNA-seq data that must be understood before one can apply such an approach to translational medicine.

关键词： RNA-seq data, Computational genomics, Statistical robustness, High-dimensional biology,Triple-negative breast cancer

Uncertainty of Climate Response to Natural and Anthropogenic Forcings Due to Different Land Use Scenarios

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Advances in Atmospheric Sciences 2011年第5期28卷 1215-1232页

作者： alexey v.ELISEEv Igor I.MOKHOv A. M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences3 Pyzhevsky 119017 Moscow Russia

The *** Institute of Atmospheric Physics,Russian Academy of Sciences （IAP RAS） climate model （CM） of intermediate complexity is extended by a spatially explicit terrestrial carbon cycle *** experiments with the IAP RAS CM are performed forced by the reconstructions of anthropogenic and natural forcings for the 16th to the 20th centuries and by combined SRES （Special Report on Emission Scenarios） A2-LUH （Land Use Harmonization） anthropogenic scenarios for the 21st ***,the impact of uncertainty in land-use scenarios on results of simulations with a coupled climate-carbon cycle model is *** simulations of the model realistically reproduced historical changes in carbon cycle *** the IAP RAS CM,climate warming reproduced in the 20th and 21st centuries enhanced terrestrial net primary production but terrestrial carbon uptake was suppressed due to an overcompensating increase in soil *** year 2100,the simulations the model forced by different land use scenarios diverged markedly,by about 70 Pg （C） in terms of biomass and soil carbon stock but they differed only by about 10 ppmv in terms of atmospheric carbon dioxide content.

关键词： terrestrial carbon cycle climate model anthropogenic scenarios uncertainty in projections

Gradient-induced long-range optical pulling force based on photonic band gap

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Light(Science & Applications) 2024年第5期13卷 865-874页

作者： Wenlong Lu alexey v.Krasavin Sheng Lan Anatoly v.Zayats Qiaofeng Dai Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and DevicesSchool of Information and Optoelectronic Science and EngineeringSouth China Normal UniversityGuangzhou 510006China Department of Physics and London Centre for Nanotechnology King’s College LondonLondon WC2R 2LSUK

Optical pulling provides a new degree of freedom in optical *** is generally believed that long-range optical pulling forces cannot be generated by the gradient of the incident ***,we theoretically propose and numerically demonstrate the realization of a long-range optical pulling force stemming from a self-induced gradient field in the manipulated *** analogy to potential barriers in quantum tunnelling,we use a photonic band gap design in order to obtain the intensity gradients inside a manipulated object placed in a photonic crystal waveguide,thereby achieving a pulling *** the usual scattering-type optical pulling forces,the proposed gradient-field approach does not require precise elimination of the reflection from the manipulated *** particular,the Einstein-Laub formalism is applied to design this unconventional gradient *** magnitude of the force can be enhanced by a factor of up to 50 at the optical resonance of the manipulated object in the waveguide,making it insensitive to *** developed approach helps to break the limitation of scattering forces to obtain longrange optical pulling for manipulation and sorting of nanoparticles and other *** developed principle of using the band gap to obtain a pulling force may also be applied to other types of waves,such as acoustic or water waves,which are important for numerous applications.

关键词： optical waveguide scattering