Two coupled Josephson junctions: dc voltage controlled by biharmonic current

Abstract

We study transport properties of two Josephson junctions coupled by an external shunt resistance. One of the junctions (say, the first) is driven by an unbiased ac current consisting of two harmonics. The device can rectify the ac current yielding a dc voltage across the first junction. For some values of coupling strength, controlled by an external shunt resistance, a dc voltage across the second junction can be generated. By variation of system parameters such as the relative phase or frequency of two harmonics, one can conveniently manipulate both voltages with high efficiency, e.g. changing the dc voltages across the first and second junctions from positive to negative values and vice versa.

Directed transport in coupled noisy Josephson junctions controlled via ac signals

“…the detailed discussion in Ref. [17]. In this case, even for α = 0 we still can find non-zero dc voltage across the first junction.…”

“…The dimensional version of the equations is presented in Ref. [17]. Here, we recall their dimensionless form, namely,…”

“…We consider two scenarions. In the first scenario (A), the ac driving to applied to only one of the junctions [15,17], namely,…”

“…[15]. Recently the dynamics of the phase difference of coupled junctions has been addressed [16,17].…”

Untitled

“…The dimensional form of the equations of motion is presented in Ref. [8]. Therein, the dimensionless variables and parameters are defined, and the dimensionless form of dynamics is presented.…”