University at Buffalo researchers have computationally predicted the optical fingerprints of 10 known defects within hexagonal boron nitride (h-BN), a honeycomb-like material used in developing future quantum technologies. The team’s models, published October 19 in Nano Letters, simulate how these atomic flaws alter the intensity and polarization of light emitted when h-BN is illuminated by a laser.

“Not all atomic defects are created equal,” says co-corresponding author Vasili Perebeinos, PhD, professor in the Department of Electrical and Computer Engineering, adding that easier defect identification brings scientists closer to finding those with desired properties. This work could allow for the precise identification and engineering of defects that emit quantum light for use in advanced communication and sensing technologies.

Simulations performed by researchers reveal that defects containing carbon atoms can produce markedly different optical fingerprints depending on their atomic arrangement. The University at Buffalo-led team modeled two distinct configurations of four carbon atoms within hexagonal boron nitride (h-BN), predicting one would emit a strong light signal in two polarization directions while the other would emit a strong signal in only one. This sensitivity to arrangement highlights the potential for detailed defect characterization beyond simply identifying the constituent atoms, an important step toward engineering quantum materials.

These fingerprints arise because defects disrupt the material’s usual response to light, altering how it absorbs and emits photons. The researchers investigated 10 different defects, including instances of missing boron or nitrogen atoms and substitutions with carbon, revealing a diverse range of optical responses.

Some defects were predicted to significantly increase light production at frequencies double or triple that of the incoming laser, potentially simplifying their experimental detection. The team’s work aims to move beyond simply detecting the presence of defects to understanding their specific properties and potential for use in quantum technologies. Defects capable of emitting single photons, individual particles of light, are particularly valuable, as these photons can carry quantum information for future communication and sensing applications.

According to Perebeinos, the ultimate objective is to gain control over defect placement within h-BN. “The ultimate goal is to create a material where we can precisely control the placement of defects that produce quantum light,” he explains.

This level of control would allow for the creation of arrays of quantum light sources, moving beyond reliance on isolated emitters. “These distinctive light responses could eventually allow us to experimentally identify not only which atoms are involved in a defect, but also precisely how they’re arranged,” says co-corresponding author Paras N. Prasad, SUNY Distinguished Professor, Samuel P. Capen Chair in the Department of Chemistry and executive director of UB’s Institute for Lasers, Photonics, and Biophotonics (ILPB).

This capability would represent an advancement in materials characterization, enabling researchers to correlate atomic structure with optical properties. The research received support from multiple sources, including the U.S. Air Force Office of Scientific Research through the Multidisciplinary University Research Initiative (MURI), the U.S. National Science Foundation, the Australian Research Council and the University at Buffalo Quantum Institute, demonstrating a broad interest in advancing the understanding and application of defects in h-BN for quantum technologies.

The ultimate goal is to create a material where we can precisely control the placement of defects that produce quantum light.
Vasili Perebeinos, PhD, professor in the Department of Electrical and Computer Engineering at the UB School of Engineering and Applied Sciences

Source: https://www.buffalo.edu/news/releases/2026/11/decoding-quantum-materials-optical-fingerprints.html

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