nl202266h_si_001.pdf (2.06 MB)
Negative and Positive Persistent Photoconductance in Graphene
journal contribution
posted on 2016-02-22, 16:22 authored by Chandan Biswas, Fethullah Güneş, Duong Dinh Loc, Seong Chu Lim, Mun Seok Jeong, Didier Pribat, Young Hee LeePersistent photoconductance, a prolonged light-induced conducting
behavior that lasts several hundred seconds, has been observed in
semiconductors. Here we report persistent negative photoconductance
and consecutive prominent persistent positive photoconductance in
graphene. Unusually large yields of negative PC (34%) and positive
PC (1652%) and remarkably long negative transient response time (several
hours) were observed. Such high yields were reduced in multilayer
graphene and were quenched under vacuum conditions. Two-dimensional
metallic graphene strongly interacts with environment and/or substrate,
causing this phenomenon, which is markedly different from that in
three-dimensional semiconductors and nanoparticles.