In this web you will find information about my research areas and a presentation of our theoretical tools to develop our work in solid state physics.

PHONONS IN MOS2 SINGLE-LAYER AND BULK

We have recently published a work about the vibrational properties of single layer and bulk MoS2 (together with WS2), a promising semiconductor, proposed as an alternative to graphene for building new transistors (Radisavljevic et. al., Nature). We have explained theoretically the last experimental results of Raman spectroscopy (Lee et. al., ACS Nano). For further information, see the publications lists.

Phonon mode E2g of MoS2 bulk

GRAPHENE

Carbon atoms arranged in a hexagonal honeycomb latttice, that is, graphene, is one of the cornerstone of our research. The recognizable linear dispersion of the bands at the Fermi level provides of novel electronic properties that makes graphene a very interesting material from both the theoretical and experimental point of view.

We study the optical properties of graphene and the dependence with the substrate. We explore how to identify the degree of chemical adsorption of graphene with the substrate. The theory of Raman spectroscopy is thus helpful for a better understanding of the interaction with the different types of substrates. For instance, graphene on Ni (111) has an strongly chemisorption that modifies significantly the Raman 2D-line, due to the modification of the electronic structure (Allard et. al.). In other metals, as gold, silver or cupper, we expect to have a weak or negligible chemisorption.

 

Representation of graphene phonons on Ni (111) substrate