High-Field EPR/ENDOR of N/Be Centers for Defect Engineering in 6H-SiC

Area of Science:

• Materials Science
• Quantum Technologies
• Solid-State Physics

Background:

• Silicon carbide (SiC) is crucial for power electronics due to its robustness under extreme conditions.
• Spin defects in SiC offer unique optical and coherent properties, making it a candidate for quantum technologies.
• Co-doping SiC with impurities like nitrogen and beryllium can tailor its properties for advanced applications.

Purpose of the Study:

• To investigate the structural and spin properties of a 6H-SiC crystal co-doped with nitrogen and beryllium.
• To characterize the electron-nuclear interactions and spin coherence of these dual impurities.
• To assess the feasibility of incorporating dual functional impurities while maintaining crystal integrity.

Main Methods:

• Continuous-wave and pulsed electron paramagnetic resonance (EPR) at W-band (94 GHz).
• Pulsed electron-nuclear double resonance (ENDOR) to probe local environments and interactions.
• TRIPLE resonance spectroscopy to verify coupled nuclear spin subspaces.

Main Results:

• Identified nitrogen donors and beryllium acceptors at various lattice sites using pulsed EPR.
• Determined phase coherence and spin-lattice relaxation times for the identified defects.
• Elucidated electron-nuclear interactions and hyperfine structures indicating delocalized spin density.
• Verified coupled nuclear spin subspaces through TRIPLE resonance spectra.

Conclusions:

• Dual impurity co-doping in SiC is feasible, with nitrogen and beryllium occupying distinct roles.
• The investigated defects exhibit delocalized spin density and coupled nuclear spin environments.
• This work supports SiC as a versatile platform for developing quantum technologies with tailored impurity functionalities.