The 197th Special MMU seminar
Magnetic Spinel Ferrite Thin Films and Heterostructures
Professor Arun Gupta
Center for Materials for Information Technology (MINT Center)
University of Alabama, Tuscaloosa, AL 35487
Date: August 6(Wed), 2014
Time: 15:30 - 16:40
Place: 8th floor medium seminar room (Room 811-812), Sengen
There is considerable interest in the growth of high quality, single
crystal spinel ferrites films because of their numerous technological
applications in areas such as microwave integrated devices, magnetoelectric
coupling heterostructures, spin Seebeck effect, and potentially as an
active barrier material in spin filter devices. We have grown high-quality,
atomically smooth epitaxial ferrite films using pulsed laser deposition and
chemical vapor deposition techniques, and carried out detailed studies of
the structural, magnetic and optical properties of the films. Of particular
interest are systematic studies on the formation of antiphase boundaries in
epitaxial ferrite films grown on different substrates and the accurate
determination of the band gap of NiFe2O4 and CoFe2O4 using optical
spectroscopy and first principles calculations. Additionally, we have grown
ferrite films on piezoelectric substrates and observed large shifts in the
ferromagnetic resonance profile due to strong magnetoelectric coupling
resulting from electrostatic field-induced changes in the magnetic
anisotropy field.