Total number
Full text
Total number
Full text
Number of local repositories
Full text
0220U000702,
0120U000267
,
Nano-hetero-structures on the base of magnetic half-metals and superconductors as promising functional materials for superconducting spintronics: electrical, magnetic and optical properties, effects of electronics topological state
Kryvoruchko Volodymyr Mykolayovych, Доктор фізико-математичних наук
14-12-2020
A.A. Galkin Physics and Engineering Institute of National Academy of Science of the Ukraine
The goals of the work - experimental research and theoretical calculations of physical properties of perspective nano-hetero-materials and establishment of scientifically substantiated principles of novel functional materials for spin electronics. Objects of research - superconductor - half-metal ferromagnet nanocomposites, crystalline and amorphous nickel films, hybrid nano-heterostructures based on superconductors and magnets. Research methods - Andreev spectroscopy; measurement of transport/resistive properties of nanocomposites; magnetic, magneto-optical, transport and optical measurements, electron microscopy studies; variations of density and volume concentration of components; theoretical modeling of transport properties of nanoscale hybrid structures based on superconductors and magnets. The transition to a superconducting state of nanocomposites from microparticles of the Bi2Sr2Ca2Cu3O6 superconductor with a d-symmetry of the order parameter (Bi2223) and nanoparticles of the magnet La2/3Sr1/3MnO3 (LSMO) - Bi2223: LSMO nanocomposites has been investigated. It is established that experimental dependences of the resistive superconducting transition and current-voltage characteristics of superconducting bulk nanocomposite samples, with the content of Bi2223: LSMO components (4: 1), are well described by the Berezinsky - Kosterlitz - Thouless model for two-dimensional superconductors. The observed transport features are due to the current flow along the ferromagnetic nanogranules LSMO, which cover Bi2223 microgranules. The influence of Ni film structure on the degree of the spin polarization of conduction electrons, as well as on other physical (mainly magnetic) properties that are essential for spin electronics, has been established. It was found that annealing of amorphous Ni films at temperatures (Tann = 300 - 350 C) causes their crystallization with the formation of FCC phase, restores their magnetic, optical, magneto-optical, and transport properties, that are typical for massive crystalline nickel. Using existing technology, Heusler alloys have been prepared for further detailed study of their electronic structure and physical properties. Single-phase Fe2CrGa alloy suitable for further study of its physical characteristics was obtained. Two- or multiphase Co2ZrGe and Co2HfGe alloys were considered unsuitable for further experimental research. Their fabrication requires improvement of the existing technology. Conductivity and current fluctuations in layered hybrid structures formed by a metal injector, nanosized insulator, normal metal layer and a superconductor have been studied. It is shown that the measurements of the shot noise and differential conductivity in such samples can serve as a source of reliable information about the presence of two energy bands with different superconducting gaps.
Дмитренко В.Ю.
Житлухіна О.С.
Кудрявцев Ю.В.
Таренков В.Ю.
Уваров М.В.
2022-03-09
Updated: 2025-12-17
Saving a scientific data set occurs in two stages:
1.) Creating a data set
Enter the name of the set, a brief description of the set (annotation), and click the “Create set” button. After that, a draft data set will be automatically created, which you can save for further work with the set. The system will redirect you to the “Data set information” page.
2.) Filling in the data
On the “Data set information” page, you need to fill in all the fields related to the data set and upload the files.
Please note! Each file is uploaded separately. This is done to ensure the stable operation of the system.
Once you have filled in the information about the scientific data set and added the necessary files, you can save the draft or send the data to the system.
Please note! Once the data has been sent, you cannot change it.
Drafts are necessary for storing the data set and editing it before sending.
All accounts on the NRA website go through a standard registration procedure and are verified. However, in order to obtain additional features, such as publishing open reviews of academic texts, verification by affiliation is required.
To obtain the status “verified”, you must change your primary email address to a corporate one, which is tied to a scientific or educational institution.
For example: user@ukrintei.ua, user@nas.gov.ua
After confirming your corporate email address, your account will be automatically verified by affiliation.
If your email address is corporate, but your account does not have a verification mark, you need to write to us at the email address NRAT@ukrintei.ua. After verification, we will add your address to the database, and your account will be verified.
After completing the verification procedure for affiliation, you can change the primary email address to a convenient one for you, without losing your status during the current verification.
You only need to verify for affiliation once.
* We use corporate addresses from the Unified State Database on Education and the State Register of Scientific Institutions Supported by the State
To search for news published on the official website of NRАT in the “News” section, you need to enter one word, several words, or an exact phrase in the search field. Different terms are separated by spaces.
The search is performed everywhere – in the title and the news text.
For a more comprehensive result, it is recommended to use word stems (parts of words without endings).
When using multiple words for the search, they are combined using one of the logical methods described below.
By default, the logical connector “and” is used. In this case, search results will include all news releases that contain the specified words, even if they are located separately from each other and are in different parts of the text.
Example: Search phrase: OECD report. Search result: all news containing the words “report” and “OECD” in the text and in the title, both together and separately.
If a phrase or phrase is enclosed in quotation marks (“), the results will include all publications where this exact phrase or phrase is found.
Example: Search phrase: “OECD report.” Search result: all news containing the exact phrase “OECD report.”
If you know the publication date of the news or are interested in a specific time frame in which they were published on the website, you can select such a date or date range in the additional field that looks like a calendar. The date is entered in the format year-month-day and confirmed by clicking on the corresponding date in the calendar dropdown. You can enter a date or choose one by browsing through the calendar by months and years. By default, the interval starts from the oldest date (2018-01-23) and ends with the current date.
You can also use one or more hashtags, which are located under the search field on the right side of the “News” page.
Please note: The search for academic texts is carried out in a separate search window at the following link https://nrat.ukrintei.ua/searchdb.
