Encapsulated Atomic Hydrogen in Octamethyl-POSS Cages: A Pulsed EPR Study

Area of Science:

• Quantum Information Science
• Materials Science
• Spectroscopy

Background:

• Polyhedral oligomeric silsesquioxane (POSS) cages can encapsulate atomic species.
• Encapsulated atomic hydrogen is a candidate for spin-based quantum technologies.
• Electron paramagnetic resonance (EPR) is crucial for probing spin properties.

Purpose of the Study:

• To investigate the spin dynamics of atomic hydrogen encapsulated in octamethyl POSS (H@Si8O12(CH3)8).
• To explore the potential of this system for quantum computing applications.
• To characterize magnetic interactions and relaxation mechanisms.

Main Methods:

• Pulsed electron paramagnetic resonance (EPR) spectroscopy.
• Hyperfine sublevel correlation (HYSCORE) spectroscopy.
• Analysis of temperature-dependent spin-lattice relaxation rates and phase memory times.
• Observation of Rabi oscillations for quantum gate probing.

Main Results:

• Detailed analysis of spin-lattice relaxation (1/T1) in terms of Raman and thermally activated processes.
• Phase memory time (T2) exhibits characteristic shortening at higher temperatures.
• Hyperfine coupling between hydrogen and 29Si nuclei was measured using HYSCORE.
• The system meets the 'matching condition' for EPR transitions.
• Room-temperature Rabi oscillations demonstrate potential for one-qubit operations.

Conclusions:

• H@Si8O12(CH3)8 exhibits favorable spin properties for quantum applications.
• The study provides a comprehensive understanding of spin relaxation mechanisms.
• The system demonstrates feasibility for performing basic quantum operations.