Parallel InAs nanowires for Cooper pair splitters with Coulomb repulsion

Carbon nanotubes as cooper-pair beam splitters.

We report on conductance measurements in carbon nanotube based double quantum dots connected to two normal electrodes and a central superconducting finger. By operating our devices as beam splitters, we provide evidence for crossed Andreev reflections tunable in situ. This opens an avenue to more sophisticated quantum opticslike experiments with spin entangled electrons.

PhD Thesis booklet Cooper pair splitting in indium arsenide nanowires

Current cross-correlations in double quantum dot based Cooper pair splitters with ferromagnetic leads.

We investigate the current cross-correlations in a double quantum dot based Cooper pair splitter coupled to one superconducting and two ferromagnetic electrodes. The analysis is performed by assuming a weak coupling between the double dot and ferromagnetic leads, while the coupling to the superconductor is arbitrary. Employing the perturbative real-time diagrammatic technique, we study the Andr...

Entanglement detection from conductance measurements in carbon nanotube Cooper pair splitters Supplemental Information

Indeed, in this situation, with filters set along the axes νaτ , ν bτ ′ (ν, ν ′ = ±) and resonant conditions such that transport is restricted to the selected levels, the density matrix for the outflowing particles takes the form ρνaτ ,νbτ′ = PνaτPν′bτ′ρPν′bτ′Pνaτ , with ρ the density matrix in the absence of spin-valley filtering. Due to the perfect splitting efficiency, the currents through t...

Entanglement detection from conductance measurements in carbon nanotube cooper pair splitters.

Spin-orbit interaction provides a spin filtering effect in carbon nanotube based Cooper pair splitters that allows us to determine spin correlators directly from current measurements. The spin filtering axes are tunable by a global external magnetic field. By a bending of the nanotube, the filtering axes on both sides of the Cooper pair splitter become sufficiently different that a test of enta...