Macroscopic quantum mechanics: experiments on Josephson junctions

Citation
Vg. Palmieri et al., Macroscopic quantum mechanics: experiments on Josephson junctions, PHYSICA B, 284, 2000, pp. 593-594
Citations number
11
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICA B
ISSN journal
0921-4526 → ACNP
Volume
284
Year of publication
2000
Part
1
Pages
593 - 594
Database
ISI
SICI code
0921-4526(200007)284:<593:MQMEOJ>2.0.ZU;2-6
Abstract
We present evidence of macroscopic quantum effects in Josephson junction at temperature well above the classical-quantum crossover temperature. The cl ear observation of quantum effects up to high temperatures has been obtaine d by measuring the tunneling rate out of a metastable state while the exter nal energy was changing with time. Thermal mixing of eingenstates does not destroy quantum effects if the rate of change of the external energy is fas t with respect to the rate of thermally induced energy transitions between levels. In our experiments this condition has been fulfilled by a suitable choice of the sweeping frequency of the external bias. (C) 2000 Elsevier Sc ience B.V. All rights reserved.