Parts | Days | Selection | Search | Updates | Downloads | Help
MA: Fachverband Magnetismus
MA 9: Cooperative Phenomena: Spin Structures and Magnetic Phase Transitions
MA 9.5: Talk
Monday, March 27, 2023, 16:15–16:30, HSZ 401
Investigating the CMR Effect in EuCd2P2 by Means of Nonlinear Transport and Fluctuation Spectroscopy — •Marvin Kopp1, Charu Garg1, Sarah Krebber1, Kristin Kliemt1, Cornelius Krellner1, Sudhaman Balguri2, Fazel Tafti2, and Jens Müller1 — 1Institute of Physics, Goethe-University Frankfurt, Frankfurt (Main), Germany — 2Departments of Physics, Boston College, USA
The colossal magnetoresistance (CMR) effect has inspired extensive studies for decades and is still the subject of intense research due to its central place in the physics of correlated electron systems as well as its potential relevance for applications. Unlike the prototypical CMR compounds based on mixed valence and double exchange in manganites or a structural Jahn-Teller distortion and ferromagnetic ordering, we focus on EuCd2P2, that exhibits a strikingly large (104 %) negative MR significantly above its antiferromagnetic ordering temperature TN = 11 K. Initial reports suggest that strong magnetic fluctuations within the layered structure could be responsible for the drastic change of resistance in the magnetic field [1]. In this work, we aim to investigate these fluctuations using higher harmonic resistance and resistance fluctuation (noise) spectroscopy. Higher harmonic measurements are sensitive to the small changes in magneto-electric coupling caused by the postulated forming of magnetic clusters (polarons), often hidden in standard resistance measurements. The dynamics of these magnetic clusters is studied using resistance noise spectroscopy as a function of temperature and magnetic field. [1] Adv. Mat., 2021, 33, 2005755.