2024/03/26 by V. M. Litvyak, Litvyak, V. M., P. S. Bazhin +7 · 1 citation
Chemistry · Physics and Astronomy · #Advanced NMR Techniques and Applications #Atomic and Subatomic Physics Research #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Rare-earth and actinide compounds
paper · pdf · doi:10.48550/arxiv.2403.17593
openalex publication_date 2024/03/26 · openalex created_date 2024/03/28 · openalex updated_date 2026/07/28
Nuclear magnetic resonance (NMR) is particularly relevant for studies of internuclear spin coupling at zero and ultra-low fields (ZULF), where spin-spin interactions dominate over Zeeman ones. Here we report on ZULF NMR in CdTe. In this semiconductor all magnetic isotopes have spin I = 1/2, so that internuclear interactions are never overshadowed by quadrupole effects. Our experiments rely on warm-up spectroscopy, a technique that combines optical pumping, additional cooling via adiabatic demagnetisation, and detection of the oscillating magnetic field-induced warm-up of the nuclear spin system via Hanle effect. We show that NMR spectra exhibit a rich fine structure, consistent with the low abundance of magnetic isotopes in CdTe, their zero quadrupole moments, as well as direct and indirect interactions between them. A model assuming that the electromagnetic radiation is absorbed by nuclear spin clusters composed of up to 5 magnetic isotopes allows us to reproduce the shape of a major part of the measured spectra.