%0 Journal Article
%T Implementation of superconductor/ferromagnet/ superconductor
%A Feofanov, A. K.
%A Oboznov, V. A.
%A Bol'Ginov, V. V.
%A Lisenfeld, J.
%A Poletto, S.
%A Ryazanov, V. V.
%A Rossolenko, A. N.
%A Khabipov, M.
%A Balashov, D.
%A Zorin, A. B.
%A Dmitriev, P. N.
%A Koshelets, V. P.
%A Ustinov, A. V.
%J Nature Physics
%D 2010
%V 6
%N 8
%F Feofanov_etal2010
%O exported from refbase (https://db.rplab.ru/refbase/show.php?record=805), last updated on Wed, 09 May 2012 11:59:41 -0500
%X High operation speed and low energy consumption may allow the superconducting digital single-flux-quantum circuits to outperform traditional complementary metal-oxide-semiconductor logic. The remaining major obstacle towards high element densities on-chip is a relatively large cell size necessary to hold a magnetic flux quantum Φ0. Inserting a π-type Josephson junction in the cell is equivalent to applying flux Φ0/2 and thus makes it possible to solve this problem. Moreover, using π-junctions in superconducting qubits may help to protect them from noise. Here we demonstrate the operation of three superconducting circuits-two of them are classical and one quantum-that all utilize such π-phase shifters realized using superconductor/ferromagnet/superconductor sandwich technology. The classical circuits are based on single-flux-quantum cells, which are shown to be scalable and compatible with conventional niobium-based superconducting electronics. The quantum circuit is a π-biased phase qubit, for which we observe coherent Rabi oscillations. We find no degradation of the measured coherence time compared to that of a reference qubit without a π-junction.
%K fromIPMRAS
%P 593-597