Enhancing optoelectronic properties of SiC-grown graphene by a surface layer of colloidal quantum dotsShow others and affiliations
2017 (English)In: Current Opinion in Chemical Engineering, E-ISSN 2211-3398, Vol. 4, no 3, article id 031001Article in journal (Refereed) Published
Abstract [en]
We report a simultaneous increase of carrier concentration, mobility and photoresponsivity when SiC-grown graphene is decorated with a surface layer of colloidal PbS quantum dots, which act as electron donors. The charge on the ionised dots is spatially correlated with defect charges on the SiC-graphene interface, thus enhancing both electron carrier density and mobility. This charge-correlation model is supported by Monte Carlo simulations of electron transport and used to explain the unexpected 3-fold increase of mobility with increasing electron density. The enhanced carrier concentration and mobility give rise to Shubnikov-de Haas oscillations in the magnetoresistance, which provide an estimate of the electron cyclotron mass in graphene at high densities and Fermi energies up to 1.2 x 10(13) cm(-2) and 400 meV, respectively.
Place, publisher, year, edition, pages
IOP PUBLISHING LTD , 2017. Vol. 4, no 3, article id 031001
Keywords [en]
SiC-graphene; unipolar charge correlation; colloidal quantum dots; Monte Carlo simulations
National Category
Materials Chemistry
Identifiers
URN: urn:nbn:se:liu:diva-139175DOI: 10.1088/2053-1583/aa76bbISI: 000403655700001OAI: oai:DiVA.org:liu-139175DiVA, id: diva2:1120205
Note
Funding Agencies|Leverhulme Trust [RPG-2013-242]; Engineering and Physical Sciences Council [EP/M012700/1]; EU
2017-07-052017-07-052023-03-31