An international research team led by Professor Dongchen Qi from the Queensland University of Technology (QUT) School of Chemistry and Physics and Professor Xiao Renshaw Wang from Nanyang Technological University in Singapore investigated the physics behind the nonlinear Hall effect (NLHE), a quantum phenomenon with significant potential for future energy-harvesting technologies.

Unlike the classical Hall effect, the NLHE can convert alternating electrical signals directly into direct current. This means energy from wireless transmissions or other ambient sources could potentially be transformed into usable electricity without relying on conventional diodes or other bulky electronic components.

"The NLHE is a sophisticated quantum phenomenon in condensed matter physics where a voltage is generated perpendicular to an applied alternating current, even in the absence of a magnetic field," Professor Qi said.

"This effect allows us to convert alternating signals straight into direct current, which is what's needed to power electronic devices. In principle, it means sensors or chips that could operate without batteries, drawing energy from their environment."

Quantum Material Shows Stable Performance at Room Temperature

To better understand how the effect works, the researchers examined a high-quality topological material known for its unusual electronic behavior.

Their experiments showed that the nonlinear Hall effect remains stable even at room temperature, an important step toward practical applications outside the laboratory.

The team also discovered that temperature plays a key role in determining both the strength and direction of the electrical voltage produced by the material.

How Defects and Atomic Vibrations Control the Effect

At lower temperatures, tiny imperfections within the material had the greatest influence on the quantum effect. As temperatures increased, naturally occurring vibrations in the crystal structure became more important.

This shift caused the direction of the generated electrical signal to reverse, revealing a previously unseen mechanism for controlling the phenomenon.

"Once you understand what's happening inside the material, you can design devices to take advantage of it," Professor Qi said.

"That's when quantum effects stop being abstract and start becoming useful -- supporting future applications ranging from self-powered sensors and wearable technology to ultra-fast components for next-generation wireless networks."

The findings provide new insight into how quantum materials behave and could help researchers develop smaller, faster, and more energy-efficient technologies that harvest power from their surroundings.