Eur. Phys. J. Special Topics 228, 697–702 (2019)
https://doi.org/10.1140/epjst/e2019-800146-1

Regular Article

Unconventional magnetic field effect on noise properties of AlO_x thin films in Kondo-like transport regime

¹ Dipartimento di Fisica “E.R. Caianiello” and CNR-SPIN Salerno, Università di Salerno, 84084 Fisciano, Salerno, Italy
² Physikalisches Institut, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
³ Dipartimento di Ingegneria, Università del Sannio, 82100 Benevento, Italy
⁴ Russian Quantum Center, National University of Science and Technology MISIS, 119049 Moscow, Russia

^a e-mail: cbarone@unisa.it

Received: 19 September 2018
Received in final form: 30 January 2019
Published online: 3 July 2019

Abstract

Granular aluminum oxide is an interesting material for application in quantum circuits. However, several issues regarding its normal state transport properties are still open. Here, detailed DC and noise transport measurements have been performed on thin films of granular Al oxide. The results evidence the presence of a Kondo-type resistivity increase at low temperatures, where specific excess 1/f noise is observed. The magnetic dependence of the excess noise further strengthens its connection with the Kondo mechanism.