ar X iv : 0 81 0 . 42 86 v 3 [ co nd - m at . s up r - co n ] 8 J an 2 00 9 Magnetic moment manipulation by a Josephson current

ar X iv : 0 80 3 . 27 76 v 1 [ co nd - m at . s up r - co n ] 1 9 M ar 2 00 8 Negative conductance in driven Josephson junctions ∗

We investigate an optimal regime of negative-valued conductance, emerging in a resistively and capacitively shunted Josephson junction, which is driven simultaneously by both, a time-periodic (ac) and a constant (dc) current. We analyze the current-voltage characteristics in the regime of absolute negative conductance. We additionally explore the stability of the negative response with respect ...

ar X iv : 0 70 7 . 42 37 v 2 [ co nd - m at . s up r - co n ] 2 3 M ar 2 00 8 Fluctuation spectroscopy of granularity in superconducting structures

We suggest to use ‘fluctuation spectroscopy’ as a method to detect granularity in a disordered metal close to a superconducting transition. We show that with lowering temperature T the resistance R(T ) of a system of relatively large grains initially grows due to the fluctuation suppression of the one-electron tunneling but decreases with further lowering T due to the coherent charge transfer o...

ar X iv : c on d - m at / 0 20 91 97 v 1 [ co nd - m at . s up r - co n ] 9 S ep 2 00 2 Oxygen Phonon Branches

Magnetic susceptibility of YbRh2Si2 and YbIr2Si2 on the basis of a localized 4f electron approach

We consider the local properties of the Yb ion in the crystal electric field in the Kondo lattice compounds YbRh2Si2 and YbIr2Si2. On this basis we have calculated the magnetic susceptibility taking into account the Kondo interaction in the simplest molecular field approximation. The resulting Curie-Weiss law and Van Vleck susceptibilities could be excellently fitted to experimental results in ...

ar X iv : c on d - m at / 0 20 63 42 v 1 [ co nd - m at . s up r - co n ] 1 8 Ju n 20 02 Andreev Level Qubit

We investigate the dynamics of a two-level Andreev bound state system in a transmissive quantum point contact embedded in an rf-SQUID. Coherent coupling of the Andreev levels to the circulating supercurrent allows manipulation and read out of the level states. The two-level Hamiltonian for the Andreev levels is derived, and the effect of interaction with the quantum fluctuations of the induced ...