Electron paramagnetic resonance (EPR) is widely used in the fields of chemistry, physics, medicine, and materials science to characterize the electronic structure of magnetic molecules and impurities. This has important applications in studying organic and inorganic free radicals, colored centers in crystals, tissue oxygenation, and archaeological dating. Performing nanoscale scanning electron paramagnetic resonance (EPR) requires three basic elements: first, a static magnetic field and magnetic field gradient are required; Secondly, a radio frequency (RF) magnetic field that can induce spin transitions is required; Finally, a sensitive detection method is needed to quantify the energy absorbed by spin.
Recently, Professor Carlos A. Gonz á lez Gi é rrez and his team from the Department of Physics and Applied Physics at the University of Massachusetts have compared the spin coupling of microwave resonators with the spin coupling generated by magnetic cavities (saturated ferromagnets and closed magnetic flux states), aiming to demonstrate that vortex cores can be used as nanoscan EPR probes, The team has developed a method of coupling ferromagnetic disks with superconducting circuits to spatially analyze the position of individual spins distributed on the surface of ferromagnetic disks, highlighting the potential of closed magnetic flux states.
Recently, Professor Carlos A. Gonz á lez Gi é rrez and his team from the Department of Physics and Applied Physics at the University of Massachusetts have compared the spin coupling of microwave resonators with the spin coupling generated by magnetic cavities (saturated ferromagnets and closed magnetic flux states), aiming to demonstrate that vortex cores can be used as nanoscan EPR probes, The team has developed a method of coupling ferromagnetic disks with superconducting circuits to spatially analyze the position of individual spins distributed on the surface of ferromagnetic disks, highlighting the potential of closed magnetic flux states.
The results show that using Py, it can be achieved at 2 π × Small droplets of 0.3 atolite were detected on the surface of 2002 nm2, containing 2 spins per nm2. In addition, the vortex core can be easily scanned by an external magnetic field for EPR scanning microscopy examination. The principle of using non dissipative spin current can also achieve the same effect, and vortex based EPR microscopy can be achieved without any external magnetic field. High spin sensitivity arises from the small mode volume of gyroscopic resonance, which is independent of material parameters such as saturation magnetization. This characteristic, coupled with the possibility of using high-frequency vortex modes, makes it possible to achieve very large spin magneton coupling.
Simulation results using Py
In summary, vortex nanocavities can also achieve strong coupling with individual spin molecule qubits, with potential applications in mediating quantum bit quantum bit interactions or implementing quantum bit readout protocols.
