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Coherent Spin Control of Single Molecules on a Surface
Philip Willke1,2,3, Tobias Bilgeri1,2,4, Xue Zhang1,2
1Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul, 03760, Republic of Korea.
ACS Nano
|November 12, 2021
Summary
Single molecular magnets offer a scalable platform for quantum technologies. Researchers achieved coherent spin control of individual iron phthalocyanine molecules on a surface, paving the way for molecular quantum information processing.
Area of Science:
- Quantum Information Science
- Molecular Spintronics
- Surface Science
Background:
- Single electron spin control is crucial for spintronics and quantum computing.
- Molecular magnets provide a flexible and scalable host for electron spins.
- Iron phthalocyanine (FePc) on magnesium oxide (MgO) forms a spin-1/2 system.
Purpose of the Study:
- To demonstrate coherent spin manipulation of individual molecules on a surface.
- To investigate decoherence mechanisms in single-molecule spin systems.
- To explore the potential for molecular arrays in quantum information processing.
Main Methods:
- Individual control of single molecules using a scanning tunneling microscope (STM).
- Electron spin resonance (ESR) techniques, including Rabi oscillation and Hahn echo measurements.
- Tunneling current-dependent measurements to identify decoherence sources.
Main Results:
- Coherent spin manipulation of individual FePc molecules achieved with a phase coherence time (T2Echo) of hundreds of nanoseconds.
- Interaction with tunneling electrons identified as the dominant decoherence mechanism.
- Molecular spin coherence in small FePc arrays is robust against intermolecular coupling and T1 spin flip events.
Conclusions:
- Individual addressable molecular spins are feasible on surfaces.
- Coherent spin control of molecules is promising for scalable quantum information processing.
- Understanding decoherence is key to advancing molecular spintronics.
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