Pair correlation and dynamic Jahn-Teller effect: High-Tc in nanoclusters

Electronic states in metallic nanoclusters form energy shells and degree of their filling depends on the number of delocalized electrons. In the region close to half-filling the cluster's geometry oscillates between the prolate and oblate configurations (dynamic Jahn-Teller effect). For large clusters ( N  > 10 2 ; N is the number of delocalized electrons) this effect competes with pair correlation and, as a result, it is perfectly realistic to observe the transition to the superconducting state. For some clusters ( e.g. , for Zn 76 , Al 70 ) the value of the critical temperature is rather high .