Silvana Abi Mershed
Advisor: Assist. Prof. Dr. Deniz Aybaş
Title: Spin dynamics in Precision Magnetometry
Abstract: Spins constitute intrinsic quantum degrees of freedom whose behavior reflects fundamental interactions governed by their environments, making them sensitive indicators of magnetic fields across nuclear, atomic and solid-state platforms.
In Nuclear Magnetic Resonance (NMR), the nuclear spin ensemble is prepared and perturbed, then left to evolve until a signal is detected. Spectral broadening is analyzed with simulations showing that gradient-induced broadening for one spin system can reproduce features commonly attributed to nuclear cross-relaxation in two spin systems. Distinguishing between sources of spectral broadening motivates precision nuclear spin applications, including dark matter searches.
In alkali vapor systems, collective atomic spins are prepared and interrogated optically while enhancing coherence and signal quality using gases, coatings and temperature. The influence of gradients and quantum noise is examined in connection with high sensitivity measurements, exemplified by magnetoencephalography (MEG) and correlated searches for exotic physics using distributed networks such as GNOME.
Nitrogen vacancy centers in diamond provide a solid-state setting in which electronic spins are initialized, driven, and readout through spin dependent fluorescence. In the sensing modalities studied, the roles of magnetic disorder, strain, and local spin baths is examined, together with applications in nanoscale NMR for biosensing applications and emerging dark matter sensing schemes.
Overall, the study highlights some of the factors that govern the behavior of spins across nuclear, atomic, and solid-state systems, clarifying the opportunities and limitations that define their use in precision magnetometry.
Date: December 25, Thursday
Time: 13:30
Place: Department of Physics seminar room SA-240