– 20 –
– 10-8 accuracy of pumped current.
Fig. 2. Current plateaus at I = nef of a hybrid single-electron turnstile measured at f = 20 MHz.
Tommy Holmqvist, Matthias Meschke, Juha Muhonen, Jukka Pekola, Joonas Peltonen, and Andrey Timofeev
Collaborators: Martti Heinonen (Mikes), Eeva Isosaari (Mikes), and Antti O. Niskanen (VTT)
We have continued the work on hysteretic Josephson junctions as threshold detectors of current noise. In particular, we managed to observe the third moment of shot noise of a tunnel junction by this technique. The full counting statistics of charge transport in mesoscopic structures has been under active theoretical investigation over the past years, but experimentally it has turned out to be hard to observe moments beyond the second one.
Other 2007 activities in the group were the further development of Coulomb blockade thermometer towards lower temperatures and, as a new direction, fabrication and experiments on suspended metallic structures. Both these activities faced challenges in 2007 and will most likely produce results in 2008.
Khattiya Chalapat, Jian Li, Sorin Paraoanu, and Kari Sarvala
Part of the KVANTTI group moved in November 2007 from the University of Jyväskylä to the LTL. In November and December Sorin Paraoanu and Jian Li of the group members worked in the LTL, while Khattiya Chalapat and Kari Sarvala remained in JyU. In the LTL, the KVANTTI group continued work started already
Annual Report 2007