Quantum study could enable battery-free energy harvesting devices

An international team of scientists, led by Professors Dongchen Qi and Xiao Renshaw Wang, has demonstrated that tiny imperfections and lattice vibrations in a quantum material can be harnessed to control the nonlinear Hall effect (NLHE), a quantum phenomenon that generates a voltage perpendicular to an alternating current without the need for a magnetic field. Unlike the classical Hall effect, which requires a magnetic field and is widely used in sensors, the NLHE enables the direct conversion of alternating signals into usable direct current without traditional diodes or bulky components. This breakthrough suggests the potential for developing smaller, more efficient energy-harvesting devices that could operate battery-free by drawing energy directly from their environment. The researchers studied a high-quality topological material exhibiting stable NLHE behavior up to room temperature. They found that the direction and strength of the voltage generated by the NLHE could be controlled by temperature: at lower temperatures, tiny material imperfections dominated the effect, while at higher temperatures, natural crystal lattice vibrations influenced the electrical signal’s