Researchers from Japan have introduced a groundbreaking method in energy harvesting, utilizing quantum physics to exceed traditional thermodynamic efficiency limits. The team, led by Professor Toshimasa Fujisawa from the Institute of Science Tokyo, collaborated with Koji Muraki, a Senior Distinguished Researcher at NTT Basic Research Laboratories. Their findings, published in Communications Physics on September 30, 2025, pave the way for more efficient energy conversion from waste heat.
Energy harvesters are devices designed to capture energy from environmental sources, such as waste heat generated by computers and power plants. Current methods are limited by thermodynamic laws, including the well-known Carnot efficiency, which caps the ratio of electrical power generated to the heat extracted from waste sources. These constraints hinder the potential for maximizing energy recovery from waste.
The research team has developed a novel technique using a non-thermal Tomonaga-Luttinger (TL) liquid, a unique one-dimensional electron system. Unlike traditional thermal systems that spread energy evenly, a TL liquid maintains its high-energy state when heat is introduced, allowing for significantly improved energy conversion efficiency.
To validate their approach, the researchers conducted an experiment where waste heat from a quantum point contact transistor was injected into a TL liquid. The energy was then transported a few micrometers to a quantum-dot heat engine, which converts heat into electricity through quantum effects. The results were striking: the TL liquid produced a higher electrical voltage and achieved greater conversion efficiency compared to conventional heat sources.
Professor Fujisawa stated, “These results encourage us to utilize TL liquids as a non-thermal energy resource for new energy-harvesting designs.” This innovative approach not only surpasses the Carnot efficiency but also exceeds the Curzon-Ahlborn efficiency, which describes efficiency at maximum power output for traditional heat engines.
The implications of this research are substantial. It suggests that waste heat from quantum computers and various electronic devices can be effectively transformed into usable power. As Fujisawa remarked, “Our findings suggest that waste heat from quantum computers and electronic devices can be converted into usable power via high-performance energy harvesting.”
This advancement holds promise for the development of more sustainable low-power electronics and could significantly improve the efficiency of energy-harvesting technologies. As the world increasingly seeks to minimize energy waste and enhance sustainability, innovations like this one represent a pivotal step forward in energy management and technology development.
With continued research in this field, future technologies may become both more powerful and environmentally friendly, addressing the global challenge of energy efficiency effectively. The potential for leveraging non-thermal quantum states in energy harvesting sets the stage for a new era in energy conversion, reinforcing the importance of integrating advanced physics into practical applications.
