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Published on: June 9, 2023
Molecular based spin qubits of Mn(II) coordination compounds with S = 5/2
Masanori Wakizaka1, Masahiro Yamashita2,3
1Department of Applied Chemistry and Bioscience, Faculty of Science and Technology, Chitose Institute of Science and Technology, 758-65 Bibi, Chitose 066-8655, Japan. ma-wakiz@photon.chitose.ac.jp.
Dalton Transactions (Cambridge, England : 2003)
|July 27, 2026
Summary
High-spin Mn(II) molecular systems (S = 5/2) offer multilevel quantum states for quantum information science. Their unique properties enable robust spin coherence and advanced quantum operations, presenting a versatile platform for next-generation quantum technologies.
Area of Science:
- Quantum Information Science
- Molecular Magnetism
- Quantum Computing
Background:
- Electron spin qubits are key for quantum information science, offering controllable superposition states and long coherence times.
- Existing molecular spin qubits primarily utilize S = 1/2 systems.
- High-spin systems present an alternative with access to multilevel quantum states.
Purpose of the Study:
- To explore the potential of high-spin manganese(II) (S = 5/2) centers as molecular spin qubits.
- To investigate the advantages of high-spin systems, particularly Mn(II), for quantum information processing.
- To highlight the suitability of Mn(II) for advanced quantum operations and next-generation quantum technologies.
Main Methods:
- Utilizing high-spin Mn(II) centers (S = 5/2) with zero orbital angular momentum (L = 0).
- Leveraging weak spin-orbit coupling in Mn(II) to suppress spin-lattice relaxation and prolong phase memory times.
- Studying Mn(II)-doped metal-organic frameworks and discrete Mn(II) complexes diluted in diamagnetic matrices.
Main Results:
- Mn(II) centers exhibit robust and stable spin coherence via the central transition (MS = -1/2 ↔ +1/2).
- Outer transitions offer additional functionality through interactions with nuclear spins and electric fields.
- Demonstrated tunable spin relaxations in Mn(II) systems, suitable for multilevel quantum units and algorithms like Grover's.
Conclusions:
- High-spin Mn(II) complexes are a promising and versatile platform for next-generation spin-based quantum technologies.
- Further research into spin-vibration coupling, structural design, and external field control is needed.
- Molecular high-spin qubits represent an emerging area with significant potential for quantum computing advancements.
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