Comunicazione
Bipolar thermoelectrical superconducting quantum interference proximity transistor (BTSQUIPT).
Guarcello C., Braggio A., Giazotto F., Citro R.
We explore the electrical transport properties of a Josephson device under a temperature gradient. We discuss the bipolar quasiparticle thermoelectric effect, generated by the spontaneous particle-hole symmetry breaking due to the thermal unbalance across the system, considering a specific device geometry. In fact, we demonstrate the feasibility of controlling the device's response by a more convenient "magnetic knob", $i.e.$, exploiting the magnetic flux through the superconducting ring enclosing one of the junction electrodes. This particular configuration allows the superconducting gap to be independently adjusted by the external magnetic flux. We discuss the peculiar behavior of the quasiparticles current as a function of both magnetic flux and temperatures, with a close look at the main thermoelectric figures of merit of the device. The possibility of controlling the superconducting gap by means of magnetic flux makes it possible for thermoelectric effects to occur even if the two electrodes are formed by the same type of superconductor, thus making the experimental realization of the device much easier, and even to relax the rather tight requirement of fine-temperature tuning.