Pushing Molecular Boundaries: Achieving Fundamental Quantum Coherence on Pristine Surfaces
On October 20, a team of physicists from the Max Planck Institute announced a groundbreaking achievement: reaching a fundamental quantum limit of optical coherence in molecules positioned on an ultra-clean surface. The researchers refined the surface of an organic crystalline material using a sublimation technique at extremely low temperatures. This approach enabled the study of individual molecules with unprecedented precision. Their findings have been published in the scientific journal Science.
This research provides the first evidence that molecules on a surface can attain the ultimate quantum level of optical coherence. To prepare the surface, the team sublimated the organic crystal and cooled it to just a few degrees above absolute zero—approximately -270 degrees Celsius. Professor Vahid Sandoghdar led the project, with Dr. Oleksiy Shkarin explaining that
“the quality of these quantum systems is measured by their coherence time—the duration during which a molecule preserves its quantum nature.”
Key Steps and Advantages
On the ultra-clean crystalline surface, molecules exhibited Fourier-limited coherence, a fundamental boundary defined by the rate of energy release into the environment. Interactions with the surface help orient molecules in specific directions and alter their energy states and vibrations. The team aims to integrate this method with atomic force microscopy to achieve local control with nanometer precision.
The essential stages of the method include:
- sublimation of the organic crystalline material,
- cooling to nearly -270 °C,
- depositing molecules via a micro-oven, and
- examining quantum coherence properties.
Placing quantum emitters on surfaces allows for precise manipulation using scanning tunneling and atomic force microscopy techniques. This breakthrough holds significant promise for advancing quantum computing and secure communication technologies.
The Max Planck Institute's work marks a crucial milestone in the evolution of quantum technologies. By enabling detailed exploration of molecular systems, it opens new pathways for progress in quantum computing, quantum cryptography, and novel material development. Employing cutting-edge molecular control on ultra-clean surfaces may lead to the creation of more powerful and efficient quantum systems in the years ahead.
In addition to these advancements, recent research has also demonstrated quantum entanglement between light and nanoparticle motion at room temperature. This breakthrough highlights the expanding possibilities in quantum physics, potentially paving the way for innovative applications in quantum computing and communication technologies.