The Ministry of Science and Technology has announced a major scientific breakthrough by researchers who have created a material that converts temperature differences into electrical signals far more effectively than previously thought possible. The discovery, made by teams from the Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), the Indian Institute of Science Bangalore, and the University of Sydney, challenges a century-old understanding of the limits of this phenomenon in solid materials.
What was discovered
Scientists created thin films of scandium nitride, a ceramic material, specially treated with magnesium to create what is called a heavily doped, highly compensated semiconductor. When one end of this material was heated and the other kept cold, it generated an electrical voltage roughly 1,000 times larger than traditional physics textbooks suggest should be possible in solid crystals.
Specifically, the material produced a Seebeck coefficient (a measure of voltage generated per degree of temperature difference) exceeding negative 124.6 millivolts per Kelvin near room temperature. This surpasses the previous known ceiling for solid materials and matches or exceeds values that were only previously seen in liquid systems such as ionic gels and electrolytes.
The researchers built a prototype light sensor using their material. When a laser illuminated one part of the device, the tiny temperature difference created produced a measurable electrical response of negative 102.4 millivolts per Kelvin. The response was fast, consistent over multiple tests, and did not damage the material.
An Indian patent application has been filed covering the materials and sensor technology emerging from this work. The findings were published in the journal Science.
What this means for you
This discovery could lead to much more sensitive temperature sensors and heat detectors for everyday use, from better thermal imaging cameras to improved Internet-of-Things devices that monitor conditions remotely. It may also enable detection of individual light particles (photons) at normal room temperature, which could advance quantum technology applications. The underlying principle that “engineered disorder” can improve material performance opens new avenues for developing sensors and devices in solid-state electronics rather than relying on liquid systems.