Investigation of power loss mechanisms by using the SdH Method of graphene structures

In this doctorate thesis, galvonomagnetic measurements of single layer graphene samples grown on SiO2/Si and SiC substrates were done. Classical Hall effect measurements which was done in low magnetic field values was done under stable magnetic circumstance and with the range of 1.8 to 275K as a function of temperature. Mangetotransport measurements have two different parts. In first part, it contains the resistance measurements, which are linked to magnetic field in different temperatures under stable electricity circumstance. In the second part, the magnetoresistance measurements, which were, linked to magnetic field in different electric field values under the lowest lattice temperatures. Magnetotransport data Rxx(B) which is to get Shubnikov-de Haas (SdH) oscillations was calculated by taking the second derivative of a function dependent with regard to the magnetic field. SdH Oscillations which are dependent on the temperature with changing relative amplitude in-plane effective mass (m*), quantum lifetime (τq) in changing magnetic field and with using periods of SdH oscillations two dimension (2D) carrier density (N2D) and Fermi energy (EF-E1) were determined. With comparing with relative amplitude of SdH oscillations which are linked to the temperature and the electricity field, electron temperature which is contrast to the electricity field and power loss were obtained. For experimental power loss mechanism, theoretical analyses were done.