Descrizione del progetto
Spiegare il mistero dei superconduttori di cuprato ad alta temperatura
La scoperta della superconduttività ad alta temperatura nei cuprati ha portato a un periodo di spettacolare fermento per l’indagine scientifica creativa e innovativa. I superconduttori di cuprato ad alta temperatura sono oggi i magneti più potenti. Dalla loro scoperta, nel 20° secolo, sono stati utilizzati in applicazioni su larga scala, quali il Large Hadron Collider. Tuttavia, il loro meccanismo rimane uno dei più grandi misteri della fisica. Il progetto CATCH-22, finanziato dall’UE, farà luce sull’argomento esplorando la fase dello «strano metallo» per chiarire il meccanismo di accoppiamento degli elettroni in alcuni superconduttori che portano ad accoppiamenti incoerenti. I risultati forniranno un modello fenomenologico coerente per la superconduttività del cuprato.
Obiettivo
CATCH-22 sets out to resolve the mystery of the cuprate high temperature superconductors. Hailed as one of the major discoveries of the 20th Century, its central mysteries – the pairing mechanism, the origin of the ‘pseudogap’ and the nature of the ‘strange metal’ phase, have remained elusive for over 30 years. Typically, what scatters electrons also binds them into pairs, and in the cuprates, the strong pairing interaction manifests itself in the strange metal phase as intense scattering, so strong in fact that it drives the electronic states required for pairing incoherent. In other words, what first promotes high temperature superconductivity ultimately destroys it! This logical paradox is the Catch-22 conundrum.
CATCH-22, the program, comprises three parts. Part 1 will explore the fate of electronic states within the strange metal phase by studying how the metallic response diminishes across universal bounds, both as a function of temperature and interaction strength, through momentum-averaged electrical conductivity and thermal diffusivity studies and momentum-resolved photoemission spectroscopy. Part 2 will seek to access the ground state of optimally doped cuprates for the first time, by applying intense current and laser pulses to ultra-thin samples in a high magnetic field. The latter, if successful, will open up a new frontier in which intense THz light and intense magnetic fields combine to access the terra incognita of hidden phases. Finally, Part 3 will explore the origins of the strange metal at the edge of the superconducting dome and search for manifestations of incoherence in other strange metals in an attempt to unify the governing principles. Given that the central mysteries are intertwined – the strange metal is a precursor to the pseudogap which in turn leads to superconductivity - CATCH-22 will aim to bring significant new insight into all three and pave the way, finally, for a coherent phenomenological model for cuprate superconductivity.
Campo scientifico
Programma(i)
Argomento(i)
Meccanismo di finanziamento
ERC-ADG - Advanced GrantIstituzione ospitante
BS8 1QU Bristol
Regno Unito