A new method for engineering light-emitting antennas uses the motion of single atoms, enabling strong coupling to free space without traditional optical cavities or waveguides. Constructing an antenna from the centre-of-mass wavefunction of one atom produces directed emission that circumvents limitations caused by atomic recoil. This approach sharply enhances cooperative scattering and enables novel quantum technologies reliant on efficient light-matter interactions.

Single atoms are engineered as light-emitting structures, circumventing conventional optical components like cavities or waveguides typically used to control light flow. Harnessing an atom’s natural movement, specifically its centre-of-mass wavefunction, achieves directed emission of light without complex physical arrangements. This innovation enhances how readily light and matter interact, potentially leading to more streamlined quantum systems suitable for various applications.

A new technique builds light-emitting antennas from individual atoms, sidestepping the need for conventional optical components such as cavities or waveguides typically used to direct light flow. The approach centres on utilising an atom’s centre-of-mass wavefunction; imagine wiggling a marble inside a box, the wavefunction describes all possible positions and movements of that marble at any given moment, to achieve directed emission, enhancing how readily light interacts with matter.

This innovation could lead to more efficient quantum systems, particularly those relying on cooperative scattering, which is akin to several people shining torches onto one spot to create a much brighter area than a single torch alone would provide. Researchers predict their method can yield cooperativity comparable to current state-of-the-art experiments using cavities or waveguides, but achieved without physical boundaries.

Centre-of-Mass Wavefunction Engineering Enables Directional Light Emission

An atom’s natural movement underpinned this work, specifically manipulating its centre-of-mass wavefunction. Quantum statistical methods involving multiple fermions, particles possessing similar properties, addressed limitations caused by photon recoil, effectively blocking disruptive channels.

New York University researchers engineered an antenna utilising the centre-of-mass movement of individual atoms, offering potential for quantum technologies. Manipulating a single atom’s wavefunction directs light emission into free space, predicting comparable cooperativity, a measure of strong light-matter coupling, to existing cavity and waveguide experiments. Employing multiple fermions within a trap enhances cooperative scattering even with tightly confined atoms; this method circumvents atomic recoil during photon emission.

Atomic wavefunctions enable enhanced single-atom cooperativity and extended range dipole interactions

Single-atom cooperativity, quantifying how strongly light interacts with matter, is now predicted to reach levels matching current optical cavity and waveguide experiments. This new approach bypasses conventional restrictions by utilising the centre-of-mass wavefunction as an antenna. Previously limited to values less than or equal to 3/2π², the technique enables directed emission without relying on complex physical structures like cavities or waveguides, offering a pathway towards more streamlined quantum systems.

Calculations reveal that resulting single-atom cooperativity is achievable with wavepacket antennas exhibiting behaviour akin to a mirror reflecting incoming light at specific wavelengths. Modifying interactions between atoms arranged in chains allows for both subradiance and superradiance, collective behaviours influencing how quickly they emit light, over distances exceeding the wavelength of emitted photons.

Atomic movement utilised as nanoscale optical antennae for enhanced quantum interfaces

Creating efficient connections between light and matter is crucial for advancing strong quantum technologies, but traditional interface construction demands intricate optical components which pose challenges when scaling up complex systems. The researchers propose an elegant solution using inherent atomic motion as antennas; constructing practical devices utilising single atoms presents considerable engineering difficulty nonetheless. This theoretical work offers an alternative pathway circumventing complex optics typically needed to control light and matter interactions, potentially simplifying future designs for quantum computers and secure communication networks by reducing component numbers. By harnessing an atom’s centre-of-mass wavefunction, describing its movement in space, directed emission of light was engineered, with strong coupling between the atom and free-space photons predicted achieving cooperativity levels comparable with existing technologies.

The research demonstrates that utilising the motion of a single atom can function as an antenna to control the direction of emitted light. This offers a way to create interfaces between light and matter without needing complex optical elements such as cavities or waveguides, potentially simplifying quantum systems. Calculations suggest this technique achieves similar efficiency to current methods using conventional optics while relying on fewer components. The authors indicate further study will focus on extending this approach to atoms with multiple energy levels for even greater control over spatial scattering patterns.

👉 More information
🗞 Strong-coupling quantum optics in free space with holes in a Fermi sea
✍️ Hao Wang, Hayden C. Orth, Duo Xu and Emily J. Davis
🧠 ArXiv: https://arxiv.org/abs/2609.15935

More like this