QUANTUM TRANSPORT IN LOW-DIMENSIONAL DISORDERED CARBON FILMS

by SOMNATH BHATTACHARYYA

Friday 19 Oct 2012, 16:00 → 17:00 Europe/Rome

Aula Conversi (Dip. di Fisica - Edificio G. Marconi)

In the framework of high-speed devices and low power non-volatile memory by using low-dimensional semiconductor super-structures we show a possible route using some novel carbon nanostructures. Negative differential resistance has been demonstrated in diamond-like carbon supperlattices with other unusual features such as n-type doping, a dimensionality crossover in conductivity and enhanced correlation length being demonstrated in nano-crystalline diamond films. These carbon structures are able to show switching of complex impedance in the range 100 GHz and a transition from diffusive to ballistic conduction. ! A model of non-linear structural disorder in quasi-1 D amorphous carbon structures is under construction and reflects some of the major features associated with conductivity in amorphous carbon. Nitrogen incorporation was considered and tunable resonance peaks inside the band gap were demonstrated. Further studies on impurity clusters show that the characteristic time can be controlled through enhanced quantum interference based on 2-D geometrical arrangement of the clusters.