Minnesota-based startup Maxwell Labs has entered into a cooperative R&D partnership with Sandia National Laboratories and the University of New Mexico to demonstrate laser-based photonic cooling for computer chips. The company is developing the technology to regulate the temperature of chips, significantly lower the power consumption, and increase the efficiency of conventional air and water-based systems. “About 30 to 40 percent of the energy data centers use is spent on cooling,” said Raktim Sarma, the lead Sandia physicist on the project. Further, he said that in some communities, the amount of water needed can strain local resources. Laser cooling occurs when a particular light frequency is matched with a very small, very pure target of a specific element. In some quantum computers, for example, lasers help hold individual atoms at super-cold temperatures. Though a laser system is not suitable to cool an entire house or any bulk materials, it could work for computer chips like GPUs if the cooling light can be focused on small, localized hot spots. “We really only have to cool down spots that are on the order of hundreds of microns,” Sarma said. Maxwell aims to use a photonic cold plate to either replace or complement water and air based cooling systems, which also allows for the resulting extracted heat in the form of light to be recycled and turned back into electricity. In some current systems, cold water flows through microscopic channels in copper cold plates laid over a chip to soak up heat. The Maxwell cold plate would be a light-based variation, designed with materials and microscopic features that channel cooling laser light to localized hot spots. According to Maxwell CEO Jacob Balma, his company’s models indicate a laser-based cooling system can keep chips colder than water-based systems. Sadhvikas Addamane, a materials scientist at Sandia National Laboratories, looks into a viewport of a molecular beam epitaxy reactor, a system Sandia will use to build experimental photonic cooling plates, designed at startup Maxwell Labs for testing. Courtesy of Sandia National Laboratories/Craig Fritz. If the models prove accurate, the cooling method could enable chips to operate harder without overheating, improving their overall performance and power efficiency simultaneously. “The unique capability of light to target and control localized heating spatially and at optical timescales for these devices unlocks thermal design constraints that are so fundamental to chip design that it is hard to speculate what chip architects will do with it — but I trust that it will fundamentally change the types of problems we can solve with computers,” Balma said. Sandia brings specialized expertise working with gallium arsenide, which makes up most of Maxwell’s cold plate design. Because laser light will heat up impurities, erasing any cooling effect, the cold plate needs to have extremely pure, thin layers of crystalline gallium arsenide, also known as epitaxial layers, to work. Through the new research agreement, Maxwell Labs will generate the technical designs, Sandia will build the devices, and the University of New Mexico will analyze their thermal performance.