Personnel of the ICMAB

Name:Martínez Perea, Benjamin
Date of assignement:Octubre, 2004
Date and place of birth:1960, El Cubillo (Cuenca)

University degrees:
Ciencias Fí­sicas, Universitat de Barcelona. 1984
Doctorat, universitat i any:
Ciencias Fí­sicas, Universitat de Barcelona. 1989
Magnetism and Magnetic Materials
Superconducting Materials
Complex Oxides
Most significative academic merits:
Member of the American Physical Society
Number of published articles:244
H Factor:34

Most significatives scientific articles:
Low temperature surface spin-glass transition in gamma-Fe2O3 nanoparticles
Authors:B. Martínez, X. Obradors, Ll. Balcells, A. Rouanet and C. Monty
Reference:Physical Review Letters Volume: 80 Issue: 1 Pages: 181-184 Published: JAN 5 1998

The Colossal Magnetoresistance of ferromagnetic manganites: structural tuning and mechanisms.
Authors:J. Fontcuberta, B. Martí­nez, A. Seffar, S. Piñol, J.L. García-Muñoz and X. Obradors.
Reference:Phys. Rev. Lett. 76, 1122 (1996)

Surface and internal spin canting in gamma-Fe2O3 nanoparticles
Authors:M.P. Morales, S. Veintemillas-Verdaguer, M.I. Montero, C.J. Serna, A. Roig, Ll. Casas, B. Martínez and F. Sadiumenge
Reference:Chemistry of Materials Volume: 11 Issue: 11 Pages: 3058-3064 Published: NOV 1999

High-field magnetoresistance at interfaces in manganese perovskites
Authors:Ll. Balcells, J. Fontcuberta, B. Martínez and X. Obradors
Reference:Physical Review B Volume: 58 Issue: 22 Pages: 14697-14700 Published: DEC 1 1998

Cationic ordering control of magnetization in Sr2FeMoO6 double perovskite
Authors:L. Balcells, J. Navarro, M. Bibes, A. Roig, B. Martínez and J. Fontcuberta
Reference:Applied Physics Letters Volume: 78 Issue: 6 Pages: 781-783 Published: FEB 5 2001

Last update: 2015-02-24 12:59:32

Research Fields:

The development of my research career has been focus basically on magnetism and magnetic materials covering both fundamental and applied aspects. I got my PhD degree at the University of Barcelona in 1989 with a work about magnetic properties of thin films and multilayers. During this training period I spent several months in different labs (University of Colorado, University of Illinois and Johns Hopkins University) working in different aspects of magnetism covering from spin waves properties in multilayers to critical phenomena and spin glasses. I joined the Department of Magnetic and Superconducting Materials in 1990 and I worked several years on different aspects of high temperature superconductors trying to determine correlations between magnetic and structural properties and materials processing. During these years I have been also working in some topics of magnetism such as small particles and geometrically frustrated systems. With the advent of the colossal magnetoresistance (CMR) phenomena by the middle of the nineties my main interest shifted to perovskite manganites on the materials side, and to spin dependent transport phenomena on the fundamental side. The development of this research line requires the use of thin films so I dedicated an intense effort to thin film preparation and characterization techniques. In the last fifteen years I have led several projects about CMR materials covering basic aspects, such as nature of the magnetic interactions, intrinsic and extrinsic MR, charge ordering, pressure effects, etc., and technological applications. The efforts in technological applications were addressed initially to the design and fabrication of CMR devices in both thick films, prepared by screen printing techniques, and thin films, prepared by sputtering. Lately, spin dependent devices, such as spin filters and magnetic tunneling junctions, have been subjects of intense research in my group. All this research effort in manganites naturally evolves to the fascinating world of strongly correlated transition metal oxides in which electron interactions strongly determine the electronic properties. Interactions among electronic spins, charges, and orbitals account for a rich variety of patterns that may form the basis for a new type of electronics. On the other hand, the strong improvement of the deposition techniques have made it possible to prepare oxide heterostructures with atomic sharp interfaces giving place to the appearance of novel phenomena and functionalities. The interplay between degrees of freedom at interfaces of complex oxides could lead to exotic and unexpected states of matter. Nowadays, may research is fully included in this exciting field covering aspects that go from the fabrication of complex oxide heterostructures to their characterization by using different techniques including sophisticated local characterization synchrotron radiation techniques.

Contact Data:

+ 34 935 801 853
Internal Phone Number:
P.O. Box:
+ 34 935 805 729
benjamin (at)
Magnetic Materials and Functional Oxides
Institut de Ciència de Materials de Barcelona

Consejo Superior de Investigaciones Científicas

Campus de la Universitat Autònoma de Barcelona

08193 Bellaterra

Catalunya, Espanya