Breakthrough at the HUN-REN Wigner Research Centre for Physics in Quantum Technology: A Step Closer to the Sensors and Computers of the Future

The research focuses on tiny, atomic-scale defects in silicon carbide (4H-SiC), which may serve as reliable building blocks for next-generation quantum technologies. These imperfections in the crystal lattice can trap individual electrons, enabling precise measurement and control of one of their fundamental properties—the spin quantum number, or intrinsic angular momentum. This capability is essential for the operation of quantum computers, quantum sensors, and quantum communication systems.

The researchers have now addressed a key challenge: how to reliably read out these quantum states, particularly at room temperature. The solution is surprisingly “mechanical” in nature: by applying controlled strain to the crystal, the distinguishability of different quantum states can be significantly enhanced. Using this method, a spin readout contrast exceeding 60% can be achieved, representing a substantial step toward practical applications.

This is particularly important because insufficient distinguishability of quantum states can severely degrade the performance of quantum devices, such as sensors. The present findings are therefore not only of theoretical importance but also contribute directly to the development of highly sensitive quantum devices capable of operating under everyday conditions.

The study, which has also been reported by Phys.org, was conducted via Hungarian–Chinese collaboration with the participation of Haibo Hu and colleagues and may open new avenues for next-generation technologies, ranging from quantum communication to biocompatible photonic devices.

According to the researchers, one of the most significant implications of their results lies in enabling the fine-tuning of quantum systems. This represents a crucial step toward transitioning quantum technologies—currently still largely in the experimental phase—into widespread practical use.

Ádám Gali, head of the National Laboratory for Quantum Information of Hungary, has recently been elected a member of the prestigious Academia Europaea.