Metal-insulator transition in co-deposited SiCu films

Several studies have shown that the superconducting transition temperatures (Tc) of many systems are enhanced near the metal–insulator transition (MIT). Other studies have demonstrated that Tc can be increased through metamaterial engineering, particularly when the dielectric function is negative and approaches zero (ENZ). To explore the correlation between the disorder-driven MIT and the ENZ condition, and their potential role in the emergence of superconductivity, a series of sputter-grown SiCu samples with varying Si/Cu content were studied. The resistivity of the samples was measured using a Physical Property Measurement System, and the room-temperature values of the dielectric function were determined via polarization reflectometry at 633 and 488 nm. The results of the transport and optical measurements on these SiCu films will be presented, and the correlation between MIT and ENZ behavior will be discussed.