Since an antiferromagnet has no net magnetic moment, most magnetic-dependent techniques will not give much information about the magnetic properties of these materials. However, using optical measurement techniques such as photoemission electron microscopy (PEEM), one can determine AFM directions through angle and temperature dependent measurements. PEEM will continue to be a useful imaging modality, especially in the early stages of development in my SHG imaging. My proposed high-resolution SHG imaging technique is similar to photoemission electron microscopy (PEEM) techniques, but has the additional advantages of being nondestructive and achievable without the need of the high intensities provided by a synchrotron source. Additionally, the improved resolution will allow examination of exciting questions that PEEM has been unable to address, such as what happens at antiferromagnetic domain walls. Could the symmetry breaking at these domain walls--an effect that might result in ferromagnetism--answer further questions about the interactions of antiferromagnets with other coupled materials?  A high-resolution SHG imaging system may very well lead to a clearer understanding of the dynamics of this system.

PHYSICS

Research Interests:

• Second harmonic generation studies in oxides, thin films and organics

• Electric control of magnetic structure

• Imaging of ferromagnetic and antiferromagnetic domains

• Exchange bias, coupling between antiferromagnets and ferromagnets

• Multifunctional materials with potential coupling with order parameters

• Piezoelectric force microscopy for the study of ferroelectric domains

• X-ray absorption spectroscopy and x-ray magnetic dichroism

• Modeling of expected dichroic contrast for different magnetic behaviors

• Internal photoemission to study spin relaxation in GaAs