Spin dynamics of exchange-coupled nitrogen donors in heavily doped n-type 15R SiC monocrystals: Multifrequency EPR and EDMR study

0579279 - FZÚ 2024 RIV US eng J - Článek v odborném periodiku
Solodovnyk, A. - Laguta, O. - Prokhorov, Andriy - Segantini, M. - Naydenov, B. - Neugebauer, P. - Greulich-Weber, S. - Kalabukhova, E. - Savchenko, Dariia
Spin dynamics of exchange-coupled nitrogen donors in heavily doped n-type 15R SiC monocrystals: Multifrequency EPR and EDMR study.
Physical Review B. Roč. 107, č. 15 (2023), č. článku 155202. ISSN 2469-9950. E-ISSN 2469-9969
Grant CEP: GA ČR(CZ) GA23-05578S; GA MŠMT(CZ) EF16_019/0000760
Grant ostatní: OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institucionální podpora: RVO:68378271
Klíčová slova: doped semiconductors * electron-paramagnetic-resonance * spin dynamics * exchange interaction
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Impakt faktor: 3.7, rok: 2022
Způsob publikování: Omezený přístup
https://doi.org/10.1103/PhysRevB.107.155202

We report on the study of nitrogen-doped 15R SiC monocrystals with (ND–NA)~51018 cm-3 using multi-frequency electron paramagnetic resonance (EPR) and electrically-detected magnetic resonance (EDMR) spectroscopic methods in the MW frequency 9.4-328.84 GHz at 4.2-300 K. A single intensive S-line with dominates the EPR spectrum in 15R SiC at T<160 K due to the exchange-coupled nitrogen (N) donors at quasi-cubic “k1” site. It was concluded that at T<90 K, the exchange coupling occurs between localized donor electrons, while at 90-150 K the interaction between exchange-coupled N donors and conduction electrons takes place. At 20-160 K, the S-line EPR width is characterized by a two-phonon Orbach relaxation process with the activation energy of ~6.5 meV corresponding to the valley-orbit splitting values for N donors in 15R SiC. The variable-range hopping regime obeying the T1/4 law takes place at T<20 K leading to the appearance of the S-line in the EDMR spectrum at low temperatures. The appearance of the EDMR signal from exchange-coupled N donors is caused by the EPR-induced temperature increase mechanism and the spin-flip hops process.
Trvalý link: https://hdl.handle.net/11104/0348133