%0 Journal Article
%T Current quantization in an optically driven electron pump based on self-assembled quantum dots
%A Nevou, L.
%A Liverini, V.
%A Friedli, P.
%A Castellano, F.
%A Bismuto, A.
%A Sigg, H.
%A Gramm, F.
%A Müller, E.
%A Faist, J.
%J Nature Physics
%D 2011
%V 7
%F Nevou_etal2011
%O exported from refbase (https://db.rplab.ru/refbase/show.php?record=841), last updated on Wed, 13 Jun 2012 19:36:07 -0500
%X The electronic structure of self-assembled semiconductor quantum dots consists of discrete atom-like states that can be populated with a well-defined number of electrons. This property can be used to fabricate a d.c. current standard that enables the unit of ampere to be independently defined. Here we report an optically pumped current source based on self-assembled InAs/GaAs quantum dots. The accuracy obtained so far is 10–1 and is limited by the uncertainty in the number of dots. At 10 K the device generates a current difference of 2.39 nA at a frequency of 1 kHz. The accuracy could be improved by site-selective growth techniques where the number of dots is fixed by pre-patterning. The results are promising for applications in electrical metrology, where a current standard is needed to close the so-called quantum metrological triangle.
%K fromIPMRAS
%P 423–427