Michael Pechan Faculty Profile »


Research Area:

Condensed matter, nanoscale magnetism

 

Experiment / Theory:

Experimental techniques: Ferromagnetic resonance, vibrating sample magnetometry, torque, ac susceptibility, magnetoresistance.

 

Research Summary:

Nanoscale magnetic systems are providing a wealth of novel phenomena in condensed matter magnetism. Of particular significance are effects arising from epitaxial and otherwise laterally constrained systems, which include ferromagnetic/semiconductor spintronic systems; exchange biased structures and patterned structures.  In all such systems magnetodynamic effects play an increasingly significant role.  For example, relaxation of the magnetization to equilibrium is a key parameter in the performance of recording media and heads.  Likewise knowledge of precession frequency and damping are crucial in the development of devices based upon spin torque phenomena.  My research explores magnetodynamics (and magnetostatics) in reduced dimensional systems such as thin film, multilayer, nanoparticle and magnetic dot based systems, as well as in single crystal Fe whiskers. Enhancements to the techniques of ferromagnetic resonance are also ongoing.  My investigations are often done in collaboration with scientists from other universities, and national and industrial laboratories.

 

Recent Publications:

 

“Exchange-coupling modified spin wave spectra in the perpendicularly magnetized permalloy nanodot chain arrays”. Jian Dou, Sarah C Hernandez *, Chengtao Yu, Michael J Pechan, Liesl Folks, Jordan A Katine, Matthew J.Carey. J. Appl. Phys. 107, 09B514 (2010).

“Enhancing remote controlled heating characteristics in hydrophilic magnetite nanoparticles via facile co-precipitation”. Reynolds A. Frimpong, Jian Dou, Michael Pechan and J.Z. Hilt. J. Magn. Magn. Mat. 322 326–331 (2010).

“Mechanisms of exchange bias in DyFe2/YFe2 exchange-coupled superlattices”. M. R. Fitzsimmons, C. Dufour, K. Dumesnil, Jian Dou and Michael Pechan. Phys. Rev. B 79, 144425 (2009).

“Exchange-coupled suppression of vortex formation in permalloy nanodot chain arrays”. Sarah Hernandez, Jian Dou, Chengtao Yu, Michael Pechan, Liesl Folks, Jordan Katine and Matthew Carey. J. Appl. Phys. 105, 07C125 (2009).