The novel spectrometer-on-a-chip. Photo: Oregon State.A team of scientists that includes an Oregon State University (OSU) materials researcher has developed a better tool for measuring light. This contribution to the field known as optical spectrometry could improve everything from smartphone cameras to environmental monitoring.
Using the two-dimensional semiconductors known as transition metal dichalcogenides, the scientists developed a powerful, ultra-tiny spectrometer that fits on a microchip and is operated using artificial intelligence (AI). This new kind of spectrometer could be readily incorporated into a variety of technologies – including quality inspection platforms, security sensors, biomedical analyzers and space telescopes. The scientists report their work in a paper in Science.
“We’ve demonstrated a way of building spectrometers that are far more miniature than what is typically used today,” said Ethan Minot, a professor of physics in the OSU College of Science. “Spectrometers measure the strength of light at different wavelengths and are super useful in lots of industries and all fields of science for identifying samples and characterizing materials.”
Traditional spectrometers require bulky optical and mechanical components, whereas the new device could fit on the end of a human hair, Minot said. This new research suggests those components can be replaced with novel semiconductor materials and AI, allowing spectrometers to be dramatically scaled down in size from the current smallest ones, which are about the size of a grape.
“Our spectrometer does not require assembling separate optical and mechanical components or array designs to disperse and filter light,” said Hoon Hahn Yoon from Aalto University in Finland, who led the study with colleague Zhipei Sun Yoon. “Moreover, it can achieve a high resolution comparable to benchtop systems but in a much smaller package.”
The device is 100% electrically controllable regarding the colors of light it absorbs, which gives it massive potential for scalability and widespread usability, the researchers say.
“Integrating it directly into portable devices such as smartphones and drones could advance our daily lives,” Yoon said. “Imagine that the next generation of our smartphone cameras could be hyperspectral cameras.” Those hyperspectral cameras could not only capture and analyze information from visible wavelengths but also allow for infrared imaging and analysis.
“It’s exciting that our spectrometer opens up possibilities for all sorts of new everyday gadgets, and instruments to do new science as well,” Minot said. In medicine, for example, spectrometers are already being tested for their ability to identify subtle changes in human tissue, such as the difference between tumors and healthy tissue.
For environmental monitoring, Minot added, spectrometers can detect exactly what kind of pollution is in the air, water or ground, and how much of it is there.
“It would be nice to have low-cost, portable spectrometers doing this work for us,” he said. “And in the educational setting, the hands-on teaching of science concepts would be more effective with inexpensive, compact spectrometers.”
Applications abound as well for science-oriented hobbyists. “If you’re into astronomy, you might be interested in measuring the spectrum of light that you collect with your telescope and having that information identify a star or planet. If geology is your hobby, you could identify gemstones by measuring the spectrum of light they absorb.”
Minot thinks that as work with two-dimensional semiconductors progresses, “we’ll be rapidly discovering new ways to use their novel optical and electronic properties.” Research into 2D semiconductors has been going on in earnest for only a dozen years, starting with the study of graphene, a one-atom-thick sheet of carbon arranged in a honeycomb lattice.
“It’s really exciting,” Minot said. “I believe we’ll continue to have interesting breakthroughs by studying two-dimensional semiconductors.”
This story is adapted from material from Oregon State University, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.