Regensburg 2019 – wissenschaftliches Programm
HL 8.4: Vortrag
Montag, 1. April 2019, 15:45–16:00, H33
Suppression of magnetic-field-induced electronic transitions in graphite microflakes — •Jose Luis Barzola Quiquia1, Christian Precker1, Markus Stiller1, Mahsa Zoragui1, Pablo Esquinazi1, Tobias Foerster2, and Thomas Herrmannsdoerfer2 — 1Felix-Bloch Institute for Solid State Physics, University of Leipzig, 04103 Leipzig, Germany — 2Hochfeld-Magnetlabor Dresden (HLD-EMFL), Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany
In this contribution we report a detailed study of the magnetoresistance of bulk and microflakes of different thickness prepared from a highly oriented pyrolytic graphite sample. Measurements have been done at different temperatures with pulsed magnetic fields up to 62 T applied parallel to the c-axis. The bulk and thicker samples show the well-known sudden jumps in the magnetoresistance in a restricted field region that were interpreted in the past as field-induced electronic phase transitions in graphite associated with, e.g., charge density waves. In the case of the thin graphite flakes the jumps in the magnetoresistance nearly vanish. In general, this suppression agrees very well with other thickness dependent results, such as the temperature dependence of the resistance, the absolute resistivity, the relative change in the magnetoresistance and the Shubnikov-de-Haas oscillations amplitude. Our results indicate that the electronic transport properties of bulk graphite are dominated by the two-dimensional electron gas formed at the interfaces between crystalline regions with the same or different stacking orders present in graphite.