Superconductor transistor and method for manufacturing such transistor

Field-effect superconductor transistor comprising a source electrode and a drain electrode, connected by a superconducting channel, the channel and the source and drain electrodes being arranged on a substrate, and a gate electrode covering the channel, wherein it comprises a layer of semiconductor material arranged between the channel and the gate electrode, so as to allow control over the critical current of the superconducting channel by controlling the surface roughness of said channel, said surface roughness being controlled by combining the proximity effect between the superconducting channel and the layer of semiconductor material, with the field effect in the layer of semiconductor material by polarising the gate electrode, said critical current being controlled between a minimum value Ic_min by reducing the surface roughness under the effect of an accumulation of semiconductor free carriers at the interface between the semiconductor layer and the channel with a first polarising voltage of the gate electrode, and a maximum value Ic_max by increasing the surface roughness under the effect of depletion of semiconductor free carriers at the interface between the semiconductor layer and the channel with a second polarising voltage of the gate electrode.