Graduation Year


Document Type




Degree Granting Department


Major Professor

Sarath Witanachchi, Ph. D.

Co-Major Professor

Pritish Mukherjee, Ph. D.

Committee Member

Hariharan Srikanth, Ph. D.

Committee Member

George S. Nolas, Ph. D.

Committee Member

Lilia M. Woods, Ph. D.


Pulsed Laser Deposition, Magnetic Anisotropy, Spintronics, Dilute Magnetic Semiconductor, Cobalt Ferrite, CoFe2O4, Lead Zirconium Titanate, PZT, Manganese or Vanadium Doped Zinc Oxide, ZnO:Mn, ZnO:V, LSMO, RKKY


Multiferroic materials exhibit unique properties such as simultaneous existence of

two or more of coupled ferroic order parameters (ferromagnetism, ferroelectricity,

ferroelasticity or their anti-ferroic counterparts) in a single material. Recent years have

seen a huge research interest in multiferroic materials for their potential application as

high density non-volatile memory devices. However, the scarcity of these materials in

single phase and the weak coupling of their ferroic components have directed the

research towards multiferroic heterostructures. These systems operate by coupling the

magnetic and electric properties of two materials, generally a ferromagnetic material and

a ferroelectric material via strain. In this work, horizontal heterostructures of composite

multiferroic materials were grown and characterized using pulsed laser ablation technique.

Alternate magnetic and ferroelectric layers of cobalt ferrite and lead zirconium titanate,

respectively, were fabricated and the coupling effect was studied by X-ray stress analysis.

It was observed that the interfacial stress played an important role in the coupling effect

between the phases. Doped zinc oxide (ZnO) heterostructures were also studied where

the ferromagnetic phase was a layer of manganese doped ZnO and the ferroelectric phase

was a layer of vanadium doped ZnO. For the first time, a clear evidence of possible room

temperature magneto-elastic coupling was observed in these heterostructures. This work

provides new insight into the stress mediated coupling mechanisms in composite