Noise Properties of YBCO Nanostructures
Artikel i vetenskaplig tidskrift, 2017

Voltage noise measurements on close to optimally doped YBa2Cu3O7-delta nanostructures have been performed. The measured resistance noise at temperature T = 96 K (above critical temperature T-C = 85 K) shows a quadratic dependence on the bias current, e.g., the voltage power spectral density S-V alpha V-2. Moreover, the normalized voltage noise S-V/V-2 is inversely proportional to the device volume. This is a clear indication that the noise is the result of an ensemble of independent resistive fluctuators, evenly distributed within the sample volume. For our structures, we obtain a product S-V/V-2 x Vol. = const. approximate to 6 x 10-(33) m(3)/Hz resulting in a Hooge's parameter 3.4 x 10(-4), which is among the lowest reported in literature. At lower temperature, T = 2 K (well below TC) the total voltage fluctuations are given by the combined effect of critical current fluctuations and resistance fluctuations. For the critical current noise, we obtain a product S-I/IC2 x Vol. = const. approximate to 6x10(-32) m(3)/Hz. The larger value of the relative critical current noise is most probably due to the fact that the critical current is determined by edge effects whereas the resistance is given by the total volume of the device.

nanostructure

HTS

noise

critical current noise

resistance noise

YBCO

flicker noise

Författare

Edoardo Trabaldo

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Marco Arzeo

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Riccardo Arpaia

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Reza Baghdadi

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Eric Andersson

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Floriana Lombardi

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

Thilo Bauch

Chalmers, Mikroteknologi och nanovetenskap (MC2), Kvantkomponentfysik

IEEE Transactions on Applied Superconductivity

1051-8223 (ISSN)

Vol. 27 4

Ämneskategorier

Fysik

DOI

10.1109/tasc.2017.2660306