More sensitive sensors and detectors based on semiconductor electronics could result from findings by researchers from the United States, Norway and Russia. Their research has yielded a decisive step in identifying the origin of the universal "1/f” noise phenomenon.

"One-over-f noise appears almost everywhere, from electronic devices and fatigue in materials to traffic on roads, the distribution of stars in galaxies, and DNA sequences," said Valerii Vinokour of Argonne's Materials Science Division. "Finding the common origin of 1/f noise in its many forms is one of the grand challenges of materials physics. Our theory establishes the origin and lower limit to 1/f noise in semiconductor electronics, helping to optimize detectors for commercial application."

In nanomaterials, as well as the microcircuits in semiconductor electronics, the noise generated by the random motion of a single electron can be devastating, since there are so few electrons in the system. Vinokour and his team showed that the 1/f noise in doped semiconductors, the platform for all modern electronics, originates in the random distribution of impurities and the mutual interaction of the many electrons surrounding them. These two ingredients — randomness and interaction — trap electrons in the Coulomb glass, a state similar to window glass where electrons move by hopping from one random location to another; 1/f noise arises from the electrons' hopping motion.

After discovering the theoretical connection between 1/f noise and formation of the Coulomb glass, Vinokour and his collaborators confirmed it with large-scale computer simulations. Suppression of the interactions was found to remove the Coulomb glass behavior and 1/f noise.