Periodic Reporting for period 1 - 4D-NMR (Single Molecule Nuclear Magnetic Resonance Microscopy for Complex Spin Systems)
Reporting period: 2023-04-01 to 2024-03-31
Our approach involves leveraging the exceptionally high 3D resolution capabilities of scanning probe microscopies (SPM), which can operate across various environments from ultra-high vacuum (UHV) to liquid. Additionally, by employing synchronized magnetic pulse excitation, we aim to incorporate the dynamics of the sample as the fourth dimension.
This transformation of NMR from a bulk measurement technique involving large ensembles of atoms to an imaging technique with sub-molecular resolution represents a groundbreaking advancement. It opens up a new avenue for interpreting resonance spectra of complex molecules and materials at the nano-scale, facilitating the identification of individual contributions within the integral signal typically measured by conventional NMR.
The ability to operate this technology in-situ in liquid environments holds particular significance for applications in life science, materials science, and chemical fields, where processes involving small amounts of chemical or biological molecules need to be detected.
Furthermore, unlike commercial NMRs that typically operate at high magnetic fields and are expensive, our developed technology will be based on simple and inexpensive electronic components. This design approach ensures that the technology will be easily accessible as an add-on for existing SPMs in the future, democratizing access to advanced NMR capabilities.
Additionally, we've been working on hardware platforms for GHz absorption spectroscopy SPM in liquid environments. We've studied two alternative implementations: a conservative approach using an arbitrary waveform generator and a vector network analyzer, and a low-cost approach using a software-defined radio or similar telecom sub-systems.
In the context of implementing an RF-pulse-SPM for magnetic GHz absorption spectroscopy, we've established a magnetic setup for localized RF-SPM characterization and tested it with magnetic materials and microfabricated structures. This setup has demonstrated excellent sensitivity in detecting local magnetic absorption effects in the GHz range, high metrological precision and spatial resolution, and measurement consistency and repeatability. Additionally, we've developed and integrated a magnetic generator with the setup, enabling signal readout in multiple frequency ranges (DC, kHz, GHz) and facilitating pulsed mode magnetic excitation.
Moving forward, we'll utilize this novel instrumentation to test its capability to detect NMR at the single-spin level using both simple and complex materials, including functional spin molecules and selected 1D and 2D magnetic materials, either in UHV or in liquid media. We have focused on synthesizing and characterizing a variety of materials for further characterization using the developed instrumentation in the project.