ICM2015 - Prof. Jose Manuel Barandiaran Semi-Plenary talk
[su_row][su_column size="1/3"]
[/su_column] [su_column size="2/3"]
Profesor Jose Manuel Barandiaran will be in the ICM2015 in Barcelona making a Semi-Plenary talk in the room F of the Cataluña Congress Palace (Palau de Congressos de Catalunya):
You can view the day program here.FERROMAGNETIC SHAPE MEMORY THIN FILMS: STRUCTURE AND MAGNETIC ANISOTROPY
JM BARANDIARAN1, VA CHERNENKO1,2, IR ASEGUINOLAZA1
1BCMaterials &University of the Basque Country (UPV/EHU), Bilbao, Spain 2Ikerbasque, the Basque Foundation for Science, Bilbao, Spain
[/su_column][/su_row] Ferromagnetic shape memory alloys (FSMA) such as off-stoichiometric Ni-Mn-Ga Heusler compounds, show the “magnetic-field-induced strain” (MFIS) effect, which is due to the mobile martensitic microstructure and the strong coupling between elastic and magnetic properties. Due to their high power density, these materials have a great potential to be used in magnetic MEMS. In the present work we overview recent advances in submicron FSMAs thin films. Particular emphasis is given to the structure of the films and to their magnetic anisotropy. Polycrystalline films deposited onto cold substrates have (220) out-of-plane fiber texture. Films grown onto hot substrates have epitaxial structures. The symmetry and strength of the magnetic anisotropy (MA) of the films have been studied by ferromagnetic resonance (FMR). They are controlled by the film crystallography, the martensitic nanostructure, the type of substrate and film thickness. The effect of the substrate in the anisotropy is demonstrated by comparing the in plane MA for a Ni-Mn-Ga film grown onto NaCl (001) and the out of plane oblique anisotropy in an identical film with the same texture deposited onto Si (001). Another important factor determining the MA is the film-substrate stress that determines the transformation volume strain. A reduction of the MA by one order of magnitude is found by FMR in single crystalline Ni-Mn-Ga films onto MgO (100). These results are explained in the framework of a magnetoelastic model of the martensite involving second- and forth-order magnetic anisotropy constants, which, thereof, can be evaluated from the experimental data. In these films the estimated value of the magnetic domain wall width is comparable with the width of the twins, indicating that the magnetic moment in neighbor twins are strongly coupled by the exchange interaction. Applications of single and double beam Si cantilevers, with deposited submicron Ni-Mn-Ga films are briefly discussed.Related news
Festival Pint of Science Bilbao 2024 (13-15 mayo)
BCMaterials colabora un año más con la edición de Bilbao del festival de divulgación científica Pint of Science. El centro ejerce también labores de coordinación del evento, que llevará a cuatro...BCMaterials-eko 2023ren urteko memoria
BCMaterials-ek 2023ko Urteko Memoria aurkeztu du. Joan den urtean zentroak izan zuen jarduera zientifikoaren alderdirik aipagarrienak biltzen ditu dokumentuak. Jarduera horrek gorantz jarraitzen du...BCMaterials abre su programa de plazas de doctorado 2024
BCMaterials ha abierto su programa de doctorado 2024 por el que ofrece 4 contratos predoctorales a estudiantes que quieran realizar su tesis en el centro. El perfil de las personas candidatas es el...Convocatoria para artículos – Número especial en ‘Polymers’
La investigadora de BCMaterials Dra. Carmen Rial ha sido seleccionado, junto con l Prof. Dr. M. Mounir Bou-Ali de la Universidad de Mondragón, como Editora Invitada del número especial de la revista...