Evolution of the line shape of radiation-induced magnetoresistance oscillations under bi-chromatic microwave excitation

ORAL

Abstract

We examine the evolution of the line shape of radiation-induced magnetoresistance oscillations under bi-chromatic microwave excitation as the microwave power level at one frequency is held fixed and the power level at the other frequency is varied. In order to overcome signal to noise issues in the limit of small oscillations at very low magnetic fields, we applied a double modulation, double lock-in technique where the magnetic field was modulated sinusoidally while applying a small ac-current to the sample. With this approach, it became possible to measure the magnetic field derivative, dRxx /dB, of the diagonal resistance, and realize more oscillations, especially in the low $B$-field limit. Thus, while using this double lock in measurement technique, the sample was bi-chromatically excited at various bichromatic microwave frequency combinations. Half cycle plots of dRxx/dB reveal that the bichromatic response magneto-transport response follows mostly low frequency response at low magnetic field region and starts following the high frequency response at high magnetic field regions. Here we present the results to address the question of whether or not superposition is followed in the bichromatic microwave magnetoresistance response.

–

Presenters

  • Binuka Gunawardana

    Physics and Astronomy, Georgia State University, Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303, USA, Department of Physics and Astronomy, Georgia State University, Physics & Astronomy, Georgia State University, Georgia State University

Authors

  • Binuka Gunawardana

    Physics and Astronomy, Georgia State University, Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303, USA, Department of Physics and Astronomy, Georgia State University, Physics & Astronomy, Georgia State University, Georgia State University

  • C.Rasadi Munasinghe

    Physics and Astronomy, Georgia State University

  • Rasanga Samaraweera

    Physics and Astronomy, Georgia State University, Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303, USA, Department of Physics and Astronomy, Georgia State University, Physics & Astronomy, Georgia State University, Georgia State University

  • Tharanga Nanayakkara

    Physics and Astronomy, Georgia State University, Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303, USA, Department of Physics and Astronomy, Georgia State University, Physics & Astronomy, Georgia State University, Georgia State University

  • Annika Kriisa

    Physics and Astronomy, Georgia State University, Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303, USA, Georgia State University, Department of Physics and Astronomy, Georgia State University, Physics & Astronomy, Georgia State University

  • U. Kushan Wijewardena

    Physics and Astronomy, Georgia State University, Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303, USA, Department of Physics and Astronomy, Georgia State University, Physics & Astronomy, Georgia State University, Georgia State University

  • Sajith Withanage

    Physics and Astronomy, Georgia State University, Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303, USA, Department of Physics and Astronomy, Georgia State University, Physics & Astronomy, Georgia State University, Georgia State University

  • Christian Reichl

    Solid State Physics, ETH Zürich, Laboratorium für Festkörperphysik, ETH Zürich, ETH Zürich, CH-8093 Zürich, Switzerland, Laboratorium für Festkörperphysik, ETH-Zurich, Solid State Physics Laboratory, ETH Zurich, Laboratorium für Festkörperphysik, ETH-Zürich, Department of Physics, ETH Zurich, Department of Physics, ETH Zurich, Switzerland, ETH Zurich

  • Werner Wegscheider

    Solid State Physics, ETH Zürich, Laboratorium für Festkörperphysik, ETH Zürich, ETH Zürich, CH-8093 Zürich, Switzerland, Laboratorium für Festkörperphysik, ETH-Zurich, Solid State Physics Laboratory, ETH Zurich, Laboratorium für Festkörperphysik, ETH-Zürich, Department of Physics, ETH Zurich, Department of Physics, ETH Zurich, Switzerland, ETH Zurich

  • Ramesh Mani

    Physics and Astronomy, Georgia State University, Department of Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303, USA, Georgia State University, Department of Physics and Astronomy, Georgia State University, Physics & Astronomy, Georgia State University