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Updated: Sep 19, 2025
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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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Optically Detected Coherent Spin Control of Organic Molecular Color Center Qubits
Sebastian M Kopp1, Shunta Nakamura1, Yong Rui Poh2
1Department of Chemistry, Institute for Quantum Information Science Research and Engineering, and Center for Molecular Quantum Transduction, Northwestern University, Evanston, Illinois 60208-3113, United States.
Journal of the American Chemical Society
|June 17, 2025
Summary
Researchers developed a new organic molecular color center using tris(2,4,6-trichlorophenyl)methyl (TTM) radicals. This advancement offers improved optical-spin interface properties for quantum information science applications.
Area of Science:
- Quantum Information Science
- Molecular Spin Chemistry
- Organic Electronics
Background:
- Solid-state defects like diamond nitrogen vacancy centers are established for quantum applications.
- Molecular optical-spin interfaces present a promising alternative with tunable properties.
Purpose of the Study:
- To report a novel organic molecular color center based on tris(2,4,6-trichlorophenyl)methyl (TTM) radicals.
- To enhance optical-spin interface performance for quantum information science.
Main Methods:
- Synthesis of a new TTM radical dimer connected by a toluene bridge.
- Utilizing spin-selective excited-state intersystem crossing for optical spin polarization.
- Coherent microwave manipulation and optical detection of spin dynamics (Rabi nutations, Hahn echo).
Main Results:
- Achieved optical polarization of the triplet ground state sublevel.
- Steric hindrance in the TTM structure increased spin selectivity and excited-state lifetimes.
- Demonstrated an order of magnitude increase in optically detected magnetic resonance contrast.
- Successfully performed coherent microwave manipulation at 85 K.
Conclusions:
- The new molecular color center exhibits enhanced performance compared to analogues.
- This work is a significant step towards using organic molecules for quantum sensing at low temperatures.
- The developed molecular system shows potential for advanced quantum information science applications.
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