Details

Autor(en) / Beteiligte

• Drichko, I. L.
• Diakonov, A. M.
• Malysh, V. A.
• Smirnov, I. Yu
• Galperin, Y. M.
• Ilyinskaya, N. D.
• Usikova, A. A.
• Kummer, M.
• von Känel, H.

Titel

Contactless measurement of alternating current conductance in quantum Hall structures

Ist Teil von

• Journal of applied physics, 2014-10, Vol.116 (15)

Ort / Verlag

Melville: American Institute of Physics

Erscheinungsjahr

2014

Quelle

AIP Journals Complete

Beschreibungen/Notizen

• We report a procedure to determine the frequency-dependent conductance of quantum Hall structures in a broad frequency domain. The procedure is based on the combination of two known probeless methods—acoustic spectroscopy and microwave spectroscopy. By using the acoustic spectroscopy, we study the low-frequency attenuation and phase shift of a surface acoustic wave in a piezoelectric crystal in the vicinity of the electron (hole) layer. The electronic contribution is resolved using its dependence on a transverse magnetic field. At high frequencies, we study the attenuation of an electromagnetic wave in a coplanar waveguide. To quantitatively calibrate these data, we use the fact that in the quantum-Hall-effect regime the conductance at the maxima of its magnetic field dependence is determined by extended states. Therefore, it should be frequency independent in a broad frequency domain. The procedure is verified by studies of a well-characterized p-SiGe/Ge/SiGe heterostructure.