Superconducting and ferromagnetic ingredients for nanohybrids
In many nanostructures, electron transport has been shown to exhibit quantum coherence and obey peculiar laws, very different from those of macroscopic and microscopic systems. These discoveries paved the way to the new field of mesoscopic physics. Within the EU-funded project LODIHYBRIDS (Correlations and proximity effect in low-dimensional and hybrid structures), scientists explored mesoscopic behaviours in hybrid systems combining materials with antagonistic properties. Among them, superconductor-ferromagnet systems were an interesting example. Ferromagnetism and superconductivity are considered antagonism phenomena, at least at first glance. While superconductivity tends to align the spins of electrons in Cooper pairs opposite to each other, ferromagnetism favours parallel alignment of magnetic moments and equally oriented spins. In hybrid nanostructures, where a non-superconducting material is in contact with a superconductor, Cooper pairs and electronic excitations are being exchanged. The LODIHYBRIDS researchers studied the so-called Andreev current induced by ferromagnetic resonance and other effects at the interface. Next, they focused on the search for Majorana bound states, a hot topic in experimental mesoscopic physics research. The generation, detection and manipulation of Majorana bound states hold the promise of topologically protected quantum computing. A hybrid system containing topological insulators or nanowires was used to identify characteristics of Majorana bound states with the aim of proposing novel ways to realise them experimentally. The consequences of topological superconductivity associated with Majorana bound states was investigated at Josephson junctions. LODIHYBRIDS findings are expected to contribute to a better understanding of hybrid systems where close contact between materials with antagonistic properties causes the emergence of unique dynamics. Such effects will have a key role to play in future quantum computers.
Keywords
Nanohybrid, nanomaterial, quantum computing, ferromagnetism, superconductivity
