SPM-THScanning Probe Microscopy Theory & Nanomechanics Group
Forces and Transport in Nanostructures
Our work is focused on ab initio modelling of different problems in Materials Science and Nanotechnology that involve forces and currents at the atomic scale. In particular, we try to understand and develop new capacities for the basic tools in Nanotechnology, the Scanning Probe Microscopes (SPMs), that enable us to use currents and forces to visualize and manipulate matter at the nanoscale.
We work, in close collaboration with experimental groups worldwide, in topics such as:
1. Scanning Tunneling (STM) and Atomic Force (AFM) Microscopes: Atomic contrast, energy dissipation mechanisms and nanomanipulation.
2. Nanomechanics: Fracture. Friction and Wear at the atomic scale. Mechanical and Transport properties of nanocontacts.
3. Adsorption, reactivity, and self-organization of fullerenes and other organic molecules on surfaces.
4. Reducible oxides for catalysis and energy harvesting applications.
5. Biomolecules: Multiscale studies of DNA and proteins in their native liquid environment.
We use a suite of total-energy methods based in Density Functional Theory (DFT) , --from very efficient codes based on local orbitals (OPENMX) to more accurate implementations with a plane-wave basis (VASP)-- in order to provide a realistic description of the mechanical and electronic properties. Transport properties are calculated with a non-equilibrium Green's function formalism, that can be naturally linked with the local orbital DFT methods.
For the biomolecular studies, we have devekoped a methodology based on steered molecular dynamics sumulations with AMBER classical force fields to characterize the adsorption and mechanical properties of large biomolecules.
H. Mönig, M. Todorović , M. Z. Baykara, T. C. Schwendemann, L. Rodrigo , E. I. Altman, R. Perez, U. D. Schwarz
Understanding Scanning Tunneling Microscopy Contrast Mechanisms on Metal Oxides: A Case Study
ACS Nano 7, 10233 (2013).  (DOI link)  (pdf)
M. M. Ugeda, D. Fernández-Torre , I. Brihuega, P. Pou , A. J. Martínez-Galera, R. Pérez , and J. M. Gómez-Rodríguez
Point Defects on Graphene on Metals
Physical Review Letters 107,116803 (2011).  (DOI link)  (pdf)  (supp. info)
M. Ondráček, P. Pou , V. Rozsíval, C. González, P. Jelínek, and R. Pérez
Forces and Currents in Carbon Nanostructures: Are We Imaging Atoms?
Physical Review Letters 106,176101 (2011).  (DOI link)  (pdf)  (supp. info)
(Editor's suggestion. Viewpoint: "Proper carbon ID required" , Physics 4,34 (2011).)
O. Custance, R. Pérez and S. Morita
Atomic force microscopy as a tool for atom manipulation
Nature Nanotechnology 4,803 (2009).  (DOI link)  (pdf)
Y. Sugimoto, P. Pou, O. Custance, P. Jelinek, M. Abe, R. Perez and S. Morita
Complex patterning by vertical interchange atom manipulation using atomic force microscopy
Science 322, 413-417 (2008) Read more. (DOI link) (pdf)
G. Otero, G. Biddau, C. Sánchez-Sánchez, R. Caillard, M. F. López, C. Rogero, F.J. Palomares, N. Cabello, M.A. Basanta, J. Ortega, J. Mendez, A.M. Echavarren, R. Pérez, B. Gómez-Lor and J. A. Martín-Gago
Fullerenes from aromatic precursors by surface-catalysed cyclodehydrogenation
Nature 464, 865-869 (2008) Read more. (DOI link) (pdf)
Y. Sugimoto,P. Jelinek, P.Pou, M. Abe, R. Perez, S. Morita and O. Custance
Chemical identification of individual surface atoms by atomic force microscopy
Nature 446, 64-67 (2007) Read more. (DOI link) (pdf)