Leila Elrgdawy

Major: Engineering
Mentors: Brad Price, Professor Mark Sherwin

PROTOTYPING ELECTRON PARAMAGNETIC RESONANCE SAMPLE HOLDER UPGRADES FOR FINE-TUNING SAMPLE AND MIRROR POSITION

Electron paramagnetic resonance (EPR) is a spectroscopic technique used to probe physical and chemical properties of matter. Due to Zeeman splitting, unpaired electrons in an applied magnetic field occupy different energy levels. To investigate their energy spectrum, (sub-THz) electromagnetic radiation is applied. When the energy of the photons emitted by the incident wave matches the difference in energy levels, energy is absorbed by the sample. At high sub-THz frequencies (>100GHz), the ability to adjust sample position to maximize the magnetic field strength of the incident 240-gigahertz wave improves the signal-to-noise ratio (SNR) of the spectrometer by as much as 6 times. The implementation of a differential screw for adjusting the sample position promises sub-micron precision, which is more achievable through custom machining than sourcing or fabricating screws with higher thread counts (approximately 100 threads per inch). Using Onshape computer-aided design software and an Original Prusa i3 MK3S+ 3D printer, sample holder upgrades could be easily iterated and prototyped. Once the differential screw design has been fully implemented, SNR is expected to improve beyond the 6 times already demonstrated.