Photo of Linxiao Zhu

Nanotechnology & materials

Linxiao Zhu

Manipulating photons to unlock efficient cooling and energy use

Year Honored


The Encyclopedia of Nature was Linxiao Zhu’s favorite book as a child and the mysterious universe described by the book piqued his curiosity. This coupled with an environment that championed ​​education, Zhu was fueled with passion for knowledge, science, and innovation.

After being admitted to the Department of Physics at the University of Science and Technology of China in 2006, Linxiao Zhu benefited from a strong academic atmosphere. He then accepted admissions for his doctoral degree from the Department of Applied Physics at Stanford University, hoping to explore the forefront of science and technology.

In the early days of his Ph.D., inspired by his supervisor, he became interested in the theoretical research of nanophotonics.

During his research, Linxiao Zhu realized that thermal radiation could also be treated as an infrared light. This meant that he could apply photonics theory and control methods of thermal radiation and explore the possibility of controlling thermal radiation with nano-photonic devices.

Based on these ideas, he found that the theory he studied had important applications, so he began to transition from theoretical research to experiments on energy conversion.

One of the interesting experiments is sky-based cooling technology. His collaborators and he designed a multilayer photonic structure that reflects 96% of sunlight through nanophotonic design. In the test, the object was able to passively cool to 5 °C below the ambient air temperature even under direct sunlight. In subsequent studies, he further boosted the temperature reduction to 42 °C.

This innovation has opened up a new field for cooling technology. The technology behind it has received patents and startups are trying to commercialize it.

"Linxiao is a remarkable scientific talent and it is quite unusual to see someone that is so outstanding in both theory and experiment," said Professor Shanhui Fan, Linxiao Zhu's doctoral supervisor, speaking highly of him.

After receiving his Ph.D. in 2016, Linxiao Zhu went to the University of Michigan and joined the mechanical engineering laboratory led by Professor Reddy and Professor Meyhofer to study laser-free refrigeration and thermophotovoltaics.

His breakthrough research led to the realization of laser-free solid-state refrigeration, which only requires applying a reverse voltage bias to a common commercial infrared light emitting diode to cool other devices. This is the first experimental realization in this field.

This refrigeration technology has a wide range of applications in wearable devices, robotics and aerospace, and could also be integrated into circuits and system-on-chips to cool electronic components directly.

To make better use of energy, Linxiao Zhu also focused on new thermal photovoltaic technology and designed a new type of thermal photovoltaic cell. By reducing the distance between a thermal emitter and a thermal photovoltaic cell to the nanoscale, he increased the electricity generation rate by 40 times.

In the future, Linxiao Zhu plans to continue research on energy conversion technologies. For example, he plans to explore solid state refrigeration using forward-biased photodiodes, and to try innovative ideas such as cooling and power generation with renewable energies.

"Whenever I encounter a new problem, I often try to analyze the problem like a newbie. Whenever I come up with a solution, I often ask myself if there is room for further improvement," said Linxiao Zhu. It is this persistence and constant introspection that led him to today's achievements.