Кафедра "Природничі науки"

Постійне посилання колекціїhttps://repository.kpi.kharkov.ua/handle/KhPI-Press/1703

Увага! Поповнення колекції кафедри "Природничі науки" від травня 2023 року тимчасово призупинено.

Офіційний сайт кафедри http://web.kpi.kharkov.ua/ken

Кафедра "Природничі науки" заснована в 1973 році.

Кафедра забезпечувала викладання дисциплін природничого циклу іноземним громадянам, які готуються продовжувати навчання у вищих навчальних закладах України.

Студенти отримують необхідний рівень знань з природничих дисциплін і мають можливість вступати в будь-які вузи України для подальшого навчання.

Кафедра входить до складу Навчально-наукового інституту міжнародної освіти Національного технічного університету "Харківський політехнічний інститут".

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2012 - 201932020 - 20211

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  • Ескіз
    Публікація
    University education in Ukraine
    (Видавничий центр НТУ "ХПІ", 2021) Khrypunova, Аlina; Hasanov, Magomedemin; Kudiy, Dmitriy; Zaitseva, Liliia
    In the study guide the basic terminological concepts of the course "University Education in Ukraine", exercises for mastering these concepts, post-text questions and tasks are considered. Designed for international students during classroom and independent work.
  • Ескіз
    Публікація
    Quantum Size Effects and Transport Phenomena in PbSe Quantum Wells and PbSe/EuS Superlattices
    (AIP Publishing LLC, 2013) Rogacheva, E. I.; Nashchekina, O. N.; Olkhovskaya, S. I.; Sipatov, A. Yu.; Dresselhaus, M. S.
    It is established that the room-temperature dependences of transport properties on the total thickness of PbSe layers d in PbSe/EuS superlattices exhibit an oscillatory behavior. It is shown that the oscillation period Δd practically coincides with the period of the thickness oscillations observed earlier in single PbSe/EuS quantum well. The non-monotonic character of these dependences is attributed to quantum size effects. The theoretically estimated and experimentally determined Δd values are in good agreement.
  • Ескіз
    Публікація
    Size effects in thin PbSe films
    (Institute of Thermoelectricity, 2012) Rogacheva, E. I.; Nashchekina, O. N.; Olkhovskaya, S. I.; Dresselhaus, M. S.
    The objects of the study are thin PbSe films with thicknesses d in the range of d = 5.5 – 410 nm, grown by thermal evaporation in vacuum of stoichiometric p-PbSe crystals on KCl substrates and covered with a EuSe layer. The room-temperature d-dependences of the Seebeck coefficient, Hall coefficient, electrical conductivity, charge carrier mobility, thermoelectric power factor are obtained. When d increases to ~ 20 nm, an inversion of the conductivity sign from p to n is observed. In the d-dependences of the transport properties one can isolate a monotonic and oscillatory components, whose presence is attributed to the manifestation of classical and quantum size effects, respectively. The oscillation periods Δd for electronic and hole gases are determined. Theoretically calculated Δd, assuming a size quantization of the electronic and hole spectra, and our estimate of the monotonic component of the electrical conductivity, using the Fuchs-Sondheimer theory, are in good agreement with the experimental data.
  • Ескіз
    Публікація
    Size Effects in Transport Properties of PbSe Thin Films
    (The Minerals, Metals & Materials Society, 2017) Rogacheva, E. I.; Nashchekina, O. N.; Menshikova, S. I.
    This paper presents an overview and analysis of our earlier obtained experimental results on the dependences of kinetic properties of single PbSe quantum wells and PbSe-based superlattices on the PbSe layer thickness d. The observed oscillatory character of these dependences is attributed to quantum size effects due to electron or hole confinement in quantum wells. Some general regularities and factors that determine the character of these quantum size effects are established. The influence of the oxidation processes and doping on the d-dependences of the transport properties is revealed. A periodic change in the conductivity type related to quantum size oscillations is detected. It is shown that the experimentally determined values of the oscillation period Dd are in good agreement with the results of theoretical calculations based on the model of a rectangular quantum well with infinitely high walls, taking into account the dependence of the Fermi energy eF on d and the availability of subbands below eF. It is established that the Dd value for the superlattices is practically equal to the Dd value observed for the single PbSe thin film.