TUNNELING SPECTROSCOPY OF MANGANITES WITH NANOSCALE STRUCTURAL NON-UNIFORMITIES

We report on our recent electron-tunneling studies of bulk manganite samples that provide important information about the structure of the near-surface layers of the material and the nature of the charge transport across them. It is shown that the even part of the differential conductance of contacts formed by a metallic injector with the surface of a manganite is a power function of the voltage bias. High voltages applied to the sample are found to locally modify the conductance of the degraded native surface layer. Experiments aimed to monitor the force applied to a metal tip pressed into the surface of a manganite prove the presence of sub-surface layers with properties significantly different from those near the surface. Experimental data are analyzed and interpreted within the Glazman–Matveev theory taking into account inelastic tunneling through two metallic "drops" inside the insulating barrier.

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Electron-tunneling analysis of defect structure in near-surface layers of conducting materials

Technical Physics Letters ◽

10.1134/s1063785012020204 ◽

2012 ◽

Vol 38 (2) ◽

pp. 193-195

Author(s):

I. V. Boylo ◽

M. A. Belogolovskii

Keyword(s):

Defect Structure ◽

Electron Tunneling ◽

Surface Layers ◽

Near Surface ◽

Conducting Materials

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Исследование механизма наноструктурирования приповерхностных слоев титана при воздействии лазерными импульсами наносекундной длительности

Письма в журнал технической физики ◽

10.21883/pjtf.2021.03.50575.18492 ◽

2021 ◽

Vol 47 (3) ◽

pp. 40

Author(s):

А.Ю. Токмачева-Колобова

Keyword(s):

Surface Layer ◽

Dynamic Recrystallization ◽

Laser Treatment ◽

Power Density ◽

Water Layer ◽

Surface Layers ◽

Near Surface ◽

Physical Mechanisms ◽

Nanosecond Pulses ◽

Irradiation Power

The microstructure of near-surface layers of submicrocrystalline (SMC) technical titanium brand VT1-0 after laser treatment under the water layer with nanosecond pulses with an irradiation power density of F=2 GW/cm2 was studied. The effect of significant reduction of the initial SMC structure to a nanostructured state in a thin near-surface layer with a thickness of about 1 µm was found. The possibility of implementing physical mechanisms of nanostructuring of near-surface layers associated with phase recrystallization or rotational dynamic recrystallization is considered.

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A generalized theory of charge transport in low-barrier Mott diodes with near-surface δ-doping: Comparison with experimental data

Russian Microelectronics ◽

10.1134/s1063739710050045 ◽

2010 ◽

Vol 39 (5) ◽

pp. 323-330 ◽

Cited By ~ 3

Author(s):

V. I. Shashkin ◽

A. V. Murel’

Keyword(s):

Experimental Data ◽

Charge Transport ◽

Near Surface ◽

Comparison With Experimental Data

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Turbulence Modeling and Simulation of Atmospheric Boundary Layers

Journal of Fluids Engineering ◽

10.1115/1.2909997 ◽

1992 ◽

Vol 114 (1) ◽

pp. 40-44 ◽

Cited By ~ 1

Author(s):

T. W. Abou-Arab ◽

M. A. Serag-Eldin

Keyword(s):

Experimental Data ◽

Surface Layer ◽

Modeling And Simulation ◽

Experimental Validation ◽

Turbulence Modeling ◽

Boundary Surface ◽

Future Research ◽

Surface Layers ◽

Atmospheric Boundary Layers ◽

Comparison With Experimental Data

The essence and shortcoming of turbulence modeling and simulation of atmospheric boundary/surface layers are discussed. The present approach rests on the extensively tested and widely used two-equation k-ε model to predict such flows. All features and constants of the standard version of the k-ε model as it is used for shear flows are retained here. This eliminates the requirement of rigorous experimental validation. However, the model with its set of boundary conditions features compatibility and realizability with the commonly reported stable, unstable and neutral atmospheric boundary/surface layer data. The paper presents also a comparison with experimental data and other models and the need for future research in this direction.

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Features of sound propagation in the presence of bubble clouds in the perturbed surface layer of the ocean

Доклады Академии наук ◽

10.31857/s0869-56524876691-695 ◽

2019 ◽

Vol 487 (6) ◽

pp. 691-695

Author(s):

V. A. Bulanov ◽

L. K. Bugaeva

Keyword(s):

Surface Layer ◽

Sound Propagation ◽

Sea Water ◽

Low Frequency ◽

Field Structure ◽

Spatial Decay ◽

Surface Layers ◽

Near Surface ◽

Spatial Restructuring ◽

Main Effect

There are contradictory views on the contribution of the near-surface layer of bubbles to the attenuation of low-frequency sound in the ocean. Taking into account the new experimental data on the distribution of bubbles in sea water, it is shown that the influence of the near-surface layer of bubbles on the structure of the spatial decay in the propagation of sound can be significant at fairly typical concentrations of bubbles in the near-surface layers of the ocean. A possible explanation for the contradictions is the spatial restructuring of the field structure, in which the main effect of the bubbles is concentrated at the near distance, at the same time not affecting the sound attenuation at the far distance.

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Milling-Induced Reset of Thermoluminescence and Deformation of Hydroxyl Species in the Near-Surface Layers of Quartz Grains

Geochronometria ◽

10.2478/v10003-008-0021-x ◽

2008 ◽

Vol 32 (-1) ◽

pp. 61-68 ◽

Cited By ~ 3

Author(s):

Akihiro Takeuchi ◽

Tetsuo Hashimoto

Keyword(s):

Surface Layer ◽

Fourier Transform ◽

Infrared Absorption ◽

The Other ◽

Surface Layers ◽

Near Surface ◽

Fourier Transform Spectrometry ◽

Infrared Absorption Spectra ◽

Blue Range ◽

Quartz Grains

Milling-Induced Reset of Thermoluminescence and Deformation of Hydroxyl Species in the Near-Surface Layers of Quartz GrainsReset mechanisms of thermoluminescence (TL) signals in the near-surface layers (~500 nm thick) of quartz grains during milling are discussed on the basis of the dependence of TL glow-curves and infrared absorption spectra on grain diameter. TL measurements (heating to 370°C at 1°C/s) indicate that the near-surface layer does not seem to emit TL at ~250-400°C, especially in the blue range, even in TL measurements after re-irradiation. In contrast, the layer seems to emit more TL at ~130°C than the inner original quartz. On the other hand, diffused reflection infrared Fourier transform spectrometry indicates that hydroxyl species (e.g. Al-OH, Li-dependent OH and molecular H2O species) are deformed in the near-surface layer. These two series of data suggest that TL recombination sites in the near-surface layer are deformed or broken during milling and contribute to TL emission unusually strongly.

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Investigation of Surface Layers of Aluminum Alloy after Superplastic Deformation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.880.190 ◽

2014 ◽

Vol 880 ◽

pp. 190-194

Author(s):

Evgeniy V. Naydenkin ◽

Konstantin V. Ivanov ◽

Gennadiy E. Rudenskii

Keyword(s):

Surface Layer ◽

Aluminum Alloy ◽

Phase Transformations ◽

Structural Phase ◽

Grain Boundary Sliding ◽

Surface Layers ◽

Near Surface ◽

Structural Phase State ◽

Ultrafine Grained ◽

Boundary Sliding

The structure and phase composition of an ultrafine-grained aluminum alloy subjected to tension under superplasticity conditions are studied. It is shown that phase transformations governed by solid solution decomposition occur in the surface layer. The rate of these phase transformations in the near-surface layer is higher due to intensive grain boundary sliding. Maximum changes of the structural-phase state of the alloy are observed in a near-surface layer of about 10 μm thick.

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