Advancements in Quantum Computing: Near-Perfect 2D Defects as Qubits

HOUSTON – June 23, 2025 – In a significant breakthrough for quantum computing, researchers from Rice University, in collaboration with Oak Ridge National Laboratory and the University of Technology, Sydney, have reported the successful development of low noise, room-temperature quantum emitters using hexagonal boron nitride (h-BN), a two-dimensional material. The study, published in *Science Advances*, details how these emitters, referred to as solid-state single-photon emitters (SPEs), can potentially serve as quantum bits or qubits, the fundamental units of information in quantum computing.

The quest for reliable qubit generation is essential for the scalability of quantum technologies, which promise to revolutionize computing, information processing, and communication. Traditional methods of generating qubits have faced challenges, particularly in maintaining stability and operational efficiency. However, the new research introduces a method that incorporates carbon doping during the synthesis of h-BN films through pulsed laser deposition (PLD). This process not only enhances the quality of the emitters but also allows for a scalable production technique.

According to Dr. Arka Chatterjee, a postdoctoral researcher at Rice University and lead author of the study, "Our work demonstrates a scalable method to create high-performance SPEs in h-BN, offering a major step toward practical quantum light sources." The significance of this research lies in its potential to address the long-standing challenges in creating stable SPEs that can emit single photons reliably at room temperature.

The research team hypothesized that introducing carbon atoms during the growth of h-BN films would create defect centers capable of emitting highly pure single photons. This hypothesis was validated through extensive testing, including photoluminescence spectroscopy and photon correlation measurements, which indicated that the carbon-doped h-BN films exhibited exceptional purity and stability in photon emission.

Dr. Shengxi Huang, an associate professor of electrical and computer engineering at Rice, emphasized the advantages of the new method, stating, "Prior attempts to create stable h-BN emitters were limited by high-temperature synthesis or postprocessing steps that compromised purity and reproducibility. Our method overcomes these barriers by integrating doping and synthesis in a single, scalable step."

The implications of this research extend beyond fundamental science; they could significantly impact various industries reliant on quantum technologies. For instance, the ability to integrate these SPEs into chip-based quantum devices and sensors may usher in a new era of quantum capabilities that were previously thought to be unattainable.

The study received support from several prestigious institutions, including the United States National Science Foundation, the Welch Foundation, and the Australian Research Council, among others. The authors stress that the content of the study reflects their findings and does not necessarily represent the views of the funding organizations.

As advances in quantum computing continue to unfold, the integration of near-perfect 2D defects as qubits marks a pivotal moment in the journey toward realizing the full potential of quantum technologies. These developments not only offer promising solutions to existing challenges but also open avenues for future research and innovation in quantum information systems.