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In a multi-branch metallic interconnect we demonstrate the possibility to induce targeted modifications of the material properties by properly selecting the intensity and polarity of the applied current. We illustrate this effect in Y-shape multiterminal devices made of Nb on sapphire for which we show that the superconducting critical current can be lowered in a controlled manner at a preselected junction. We further observe the gradual appearance of Fraunhofer-like critical current oscillations with magnetic field which indicates the gradual modification of a superconducting weak link. This method permits progressive modifications of a hand-picked junction without affecting the neighboring terminals. The proposed approach has the benefit of being inexpensive and requiring conventional electronics. This technique represents a major step toward all-electric control of multiterminal Josephson junctions.

The Wiedemann-Franz law states that the charge conductance and the electronic contribution to the heat conductance are proportional. This sets stringent constraints on efficiency bounds for thermoelectric applications, which seek a large charge conduction in response to a small heat flow. We present experiments based on a quantum dot formed inside a semiconducting InAs nanowire transistor, in which the heat conduction can be tuned significantly below the Wiedemann-Franz prediction. Comparison with scattering theory shows that this is caused by quantum confinement and the resulting energy-selective transport properties of the quantum dot. Our results open up perspectives for tailoring independently the heat and electrical conduction properties in semiconductor nanostructures.

We demonstrate gate control of electronic heat flow in a thermally biased single-quantum-dot junction. Electron temperature maps taken in the immediate vicinity of the junction, as a function of the gate and bias voltages applied to the device, reveal clearly defined Coulomb diamond patterns that indicate a maximum heat transfer at the charge degeneracy point. The nontrivial bias and gate dependence of this heat valve results from the quantum nature of the dot at the heart of device and its strong coupling to leads.

We report on the first measurement of the Seebeck coefficient in a tunnel-contacted and gate-tunable individual single-quantum dot junction in the Kondo regime, fabricated using the electromigration technique. This fundamental thermoelectric parameter is obtained by directly monitoring the magnitude of the voltage induced in response to a temperature difference across the junction, while keeping a zero net tunneling current through the device. In contrast to bulk materials and single molecules probed in a scanning tunneling microscopy (STM) configuration, investigating the thermopower in nanoscale electronic transistors benefits from the electric tunability to showcase prominent quantum effects. Here, striking sign changes of the Seebeck coefficient are induced by varying the temperature, depending on the spin configuration in the quantum dot. The comparison with numerical renormalization group (NRG) calculations demonstrates that the tunneling density of states is generically asymmetric around the Fermi level in the leads, both in the cotunneling and Kondo regimes.

Specialist tutors have to transfer two types of knowledge to doctors who are specialising in a particular clinic: public declarative knowledge, including facts, notions, principles in that particular field; and their own private procedural knowledge acquired in years of direct experience. Embodying this knowledge into an expert system means that this information can be shared more rapidly, and tutoring is easier. This paper presents a tutorial expert system for neurological clinics which can emulate the diagnostic process of an expert neurologist for neurogenic diseases of the lower limbs, assist users in planning the optimal sequence of NG and EMG tests, interpret the results of these tests, and help users to achieve the most suitable diagnosis.