Scientists at Eindhoven University of Technology (TU/e) have achieved a major advance in energy transfer, demonstrating that energy can move between microscopic particles over distances measured in millimetres without being lost as heat or light.
The research team, led by Professor Jaime Gómez Rivas alongside researchers Jie Ji and Wouter Holman, developed a surface made of precisely arranged gold nanorods that enables highly efficient energy transfer.
Their findings were published in Science Advances and challenge long-held assumptions about the distance over which radiation-free energy movement can occur.
The result could have significant implications for quantum communication, solar energy technologies, chemical engineering, and next-generation medical sensors.
By extending the range of coherent energy transfer far beyond previously accepted limits, the work opens new possibilities for controlling energy at the nanoscale.
The importance of energy transfer
In most systems, energy absorbed by a molecule is eventually released into its surroundings as heat or emitted as light.
A special phenomenon known as Förster Resonance Energy Transfer (FRET) works differently. Instead of radiating away, energy moves directly from one molecule to another through electromagnetic interactions.
This process is remarkably efficient because virtually no energy is lost during the transfer. Nature relies on it extensively. During photosynthesis, plants use this mechanism to move captured solar energy rapidly to locations where it can be converted into chemical energy.
Scientists also use FRET as a powerful analytical tool. Because the effect occurs only when molecules are extremely close together, it allows researchers to measure molecular distances and study biological processes with exceptional precision.
The challenge has always been range. Traditional FRET operates only across distances of a few nanometers, making long-range energy transfer impossible under normal conditions.
Breaking through a fundamental barrier
The TU/e team has now demonstrated a method that extends efficient energy transfer from the nanometer scale to distances of several millimetres.
Although a few millimetres may appear modest in everyday terms, it represents an enormous leap in the microscopic world. The increase is many orders of magnitude beyond the range typically associated with conventional FRET-based interactions.
The breakthrough relies on an unusual physical phenomenon known as a bound state in the continuum (BIC).
These electromagnetic states remain trapped within a structure rather than radiating outward into the surrounding environment. As a result, energy can remain confined and preserved for extended periods.
How gold nanorods enable long-range energy transfer
To harness this effect, researchers created a flat surface containing microscopic gold rods arranged in an exceptionally precise pattern on glass.
When the surface was excited at a specific frequency, a BIC state formed. This state allowed energy to travel between two measurement probes separated by approximately two millimetres while remaining confined to the surface.
The transfer occurs through resonances within the gold rods. Under ordinary conditions, such resonances would emit photons, causing energy losses. In the new system, however, the BIC prevents radiation from escaping, preserving the integrity of the energy transfer process.
Researchers also observed a strong directional effect. Energy moved efficiently along one orientation of the gold rod array but weakened much more rapidly in the perpendicular direction.
This built-in directionality could provide a powerful mechanism for controlling energy flow in future photonic and quantum devices.
Potential applications in technology and medicine
One of the most notable aspects of the achievement is that it operates on a flat surface at room temperature. The system does not require optical fibres, waveguides, or complex cryogenic cooling equipment, as many advanced quantum technologies do.
Because the transferred energy retains its information as it moves through the structure, the platform may support future quantum communication systems that require coherent information transport.
The discovery could also improve ultrasensitive biosensors capable of detecting individual molecules with unprecedented accuracy. Enhanced energy transfer mechanisms may increase signal strength while reducing losses, making diagnostic technologies more effective.
Looking further ahead, researchers believe the approach could enable interactions among large networks of molecules rather than isolated pairs.
Such coherent molecular assemblies, sometimes described as “supermolecules,” could alter chemical behaviour and create entirely new opportunities for materials science and chemistry.
A new chapter for energy transfer research
The study represents a significant step forward in understanding and controlling energy transfer.
By combining bound states in the continuum with carefully engineered gold nanostructures, researchers have shown that radiation-free energy movement can occur over distances previously considered unattainable.
As scientists continue exploring practical applications, this breakthrough may help shape future advances in renewable energy, quantum technologies, molecular sensing, and nanoscale engineering.