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Updated: May 9, 2026
08:22
Measurement of Ultrafast Vibrational Coherences in Polyatomic Radical Cations with Strong-Field Adiabatic Ionization
Published on: August 6, 2018
Quantum Phase Transition of a Molecular Radical Pair
Xin Li1, Tie-Feng Fang2, Yang He3
1Center for Carbon-Based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices, School of Electronics, Peking University, Beijing 100871, China.
Journal of the American Chemical Society
|May 7, 2026
Summary
Researchers demonstrated a controllable quantum phase transition in molecular spin pairs, switching between antiferromagnetic and ferromagnetic states using magnetic fields. This breakthrough offers a tunable platform for exploring quantum phenomena in molecular systems.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Molecular magnetism
Background:
- Quantum phase transitions are fundamental in condensed matter physics.
- Observing these transitions requires precisely engineered materials.
- Molecular spin systems offer a promising avenue for studying quantum phenomena.
Purpose of the Study:
- To demonstrate and investigate a quantum phase transition in artificial molecular spin pairs.
- To show controllable switching between antiferromagnetic and ferromagnetic ground states.
- To establish a tunable platform for exploring quantum phase transitions in molecular systems.
Main Methods:
- Utilizing scanning tunneling microscopy experiments.
- Performing theoretical calculations.
- Engineering artificial molecular spin pairs.
Main Results:
- Demonstrated a controllable quantum phase transition in molecular spin pairs.
- Showcased the ability to switch ground states between antiferromagnetic and ferromagnetic phases via magnetic fields.
- Revealed tunable critical behavior through modulation of intermolecular interactions.
Conclusions:
- Artificial molecular spin pairs provide a practical platform for studying quantum phase transitions.
- The observed quantum phase transition is controllable and tunable.
- Microscopic details and critical behavior of the transition were elucidated.
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