1. Nicholas J. Savino Lynchburg College Department of Physics
Characterization of Magnetic Thin Films using the Magneto Optic Kerr Effect
Nicholas J. Savino
Lynchburg College
Department of Physics

2. Magnetization "Hysteresis Loop and Magnetic Properties." NDT
Resource Center. NSF-ATE, n.d. Web.

3. Magneto Optic Kerr Effect (MOKE)
Polarized Light Beam
Initial Polarization
Change in Polarization
Sample
Kerr, John. “XLIII. On Rotation of the Plane of Polarization by
Reflection from the Pole of a Magnet.” Philosophical
Magazine, vol. 3, no. 19, ser. 5, 1877, pp. 321–343.
Davidson, Michael W. “John Kerr.” Molecular
Expressions: Science, Optics and You, National High
Magnetic Field Laboratory, 13 Nov

4. Thin Films Thin film of Ni and FePd (40 to 400 nm thick)
Si wafer (0.1 to 1 mm thick)

5. Crossed Polarizers Laser Photodetector Polarizer Chopper Analyzer
Electromagnet
Crossed Polarizers

7. "Hysteresis Loop and Magnetic Properties." NDT
Resource Center. NSF-ATE, n.d. Web.

8. Data Hysteresis loop created by the Ni sample
Hysteresis loop created by the FePd sample

9. Applications
Biebel , Harald. “Brilliant Hard Drive Quality with Magnetic
Field Sensors Made of Diamond.” Phys.org,
Fraunhofer Gesellschaft, 30 June 2016.

10. Future Work More samples
Cooling system allowing stronger magnetic field
Applying fields at different orientations B B
R.A. Lukaszew et al. / Applied Surface Science 219 (2003)

11. Acknowledgements
Lukaszew Research Group at College of William and Mary, provided FePd capped with Au sample
Dr. William Roach, research advisor
NewMarket Corporation, Virginia Foundation for Independent Colleges, Summer Undergraduate Science Research Fellowship

12. Questions?

13. LabVIEW Block Diagram

14. Calibration

15. Methodology Lock-in and chopper set to 650 Hz
Polarizer oriented at approximately 320 degrees, analyzer oriented at approximately 170 degrees, nearly crossing the two
The samples tested were:
100 nm Ni thin film sample on Si wafer (Ni)
100 nm Ni thin film sample on 300 nm SiO2 on Si wafer (Ni on SiO2)
40 nm FePd thin film sample capped with 5 nm Au (FePd capped with Au)

16. Comparing Orientations
Hysteresis loops created by Ni sample in orientation 1 in blue, orientation 2 in orange
Hysteresis loops created by Ni (on SiO2)sample in orientation 2 in black, orientation 1 in red

17. Thank you!