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Updated: Jul 15, 2025
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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
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Molecular van der Waals Fluids in Cavity Quantum Electrodynamics.
John P Philbin1,2, Tor S Haugland3, Tushar K Ghosh4
1Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States.
The Journal of Physical Chemistry Letters
|September 29, 2023
Summary
Strong light-matter coupling controls thermodynamic properties of molecules. This study reveals how cavity quantum electrodynamics and machine learning enable precise control over molecular interactions and orientational order in many-molecule systems.
Area of Science:
- Chemical Physics
- Quantum Optics
- Computational Chemistry
Background:
- Intermolecular van der Waals interactions are fundamental to diverse chemical and physical processes.
- Controlling these interactions is key to understanding phenomena from biomolecular binding to material properties.
Purpose of the Study:
- To demonstrate strong light-matter coupling as a method for controlling thermodynamic properties in many-molecule systems.
- To investigate orientation-dependent energies and interactions of van der Waals molecules within optical cavities.
Main Methods:
- Utilized *ab initio* cavity quantum electrodynamics calculations.
- Developed machine-learning-based interaction potentials for molecules inside optical cavities.
- Simulated systems of hydrogen molecules (H2) ranging from 12 to 144 molecules.
Main Results:
- Revealed orientation-dependent single molecule and interaction energies, with distance dependencies of R-3 and R0.
- Observed varying degrees of orientational order in H2 systems due to cavity-modified interactions.
- Identified key factors influencing orientational order: quantum nuclear effects, light-matter coupling strength, cavity modes, molecular anisotropy, and system size.
Conclusions:
- Strong light-matter coupling offers a powerful route to manipulate molecular interactions and thermodynamic behavior.
- Machine learning potentials derived from cavity quantum electrodynamics are effective for simulating complex molecular systems.
- The degree of orientational order is highly sensitive to quantum effects and system parameters within optical cavities.
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