A new method for creating large ultrathin infrared sensors that eliminate the need for cryogenic cooling has the potential to revolutionize night vision technology for military applications and autonomous vehicles. Current night vision systems, particularly thermal ones, tend to be bulky, consume significant power, and rely on cooling components, which may be difficult to acquire, especially in the context of potential conflicts involving China.
The U.S. Air Force, Army, and special operations forces have increasing demands for advanced night vision solutions, as do manufacturers of next-generation autonomous vehicles. Researchers from the Massachusetts Institute of Technology (MIT), along with teams from the University of Wisconsin-Madison, Rensselaer Polytechnic Institute, and Seoul National University, published a study in Nature detailing a technique called “atomic lift-off” (ALO). This technique allows the creation of ultra-thin layers of special crystal materials that are self-supporting and do not need to adhere to traditional substrates like graphene. The resulting materials are less than 10 nanometers thick.
Conventional infrared sensors, such as mercury cadmium telluride (MCT) detectors, require maintenance at extremely low temperatures (around -321°F), necessitating heavy and power-intensive cooling systems. The new research introduced a solution by utilizing an ultra-thin film made from PMN-PT, a material capable of detecting minuscule heat variances with unprecedented sensitivity—approximately 100 times that of older materials like lithium tantalate.
One of the significant advantages of PMN-PT sensors is their ability to operate at room temperature, enabling detection across the far-infrared spectrum without the need for cooling. This capability could transform the design and functionality of night vision and thermal detection systems. In their experiments, the researchers successfully produced larger and thinner sensor films while maintaining the integrity of the crystal structure. Specifically, they created membranes measuring 10 nanometers in thickness and 10 millimeters in width—analogous to the size of a fingernail—and manufactured infrared sensor arrays with slightly thicker membranes (80 nanometers) that all functioned correctly.
These sensors demonstrated stability over time and retained their performance without heavy cooling setups, matching the effectiveness of the best current cooled infrared detectors. The project received support from the Air Force Office of Scientific Research and the U.S. Department of Energy.
The U.S. military is pursuing advancements in night vision that do not depend on materials sourced from foreign countries, particularly China, which is a leading supplier of thermal imaging equipment and essential minerals, such as germanium and chalcogenide, used in thermal lenses. This research heralds a more independent approach to developing night vision capabilities, emphasizing faster, cheaper, and more locally sourced manufacturing processes.
