New '1/f noise' discovery promises to improve semiconductor-based sensors

May 9, 2007
New '1/f noise' discovery promises to improve semiconductor-based sensors
Illustration of a Coulomb glass system: Electrons (red) in a random landscape, interacting with each other (yellow-orange lines). Noise of the resistance of the system is created by collective "hopping" of the electrons (green arrow). Credit: Argonne National Laboratory

More sensitive sensors and detectors based on semiconductor electronics could result from new findings by researchers from the United States, Norway and Russia.

Their research has yielded a decisive step in identifying the origin of the universal "one-over-f" (1/f) noise phenomenon; “f” stands for "frequency."

"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 or Argonne's Materials Science Division. "Finding the common origin of one-over-f noise in its many forms is one of the grand challenges of materials physics. Our theory establishes the origin and lower limit to one-over-f noise in semiconductor electronics, helping to optimize detectors for commercial application."

Noise is a fluctuation in time, a deviation from the average. Humans and other animals carry a common example in their heartbeats, where 1/f noise can be detected as a deviation from normal pulse. In nanomaterials, such as the tiny circuits 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.

Vinokur 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 like 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, Vinokur 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.

“Our results," Vinokour said, "establish that one-over-f noise is a generic property of Coulomb glasses and, moreover, of a wide class of random interacting systems and phenomena ranging from mechanical properties of real materials and electric properties of electronic devices to fluctuations in the traffic of computer networks and the Internet.”

These research findings were published in the May 11 issue of Physical Review Letters.

Source: Argonne National Laboratory

Explore further: X-ray studies could help make LIGO gravitational wave detector 10 times more sensitive

Related Stories

Algorithm ensures that random numbers are truly random

June 24, 2016

(Phys.org)—Generating a sequence of random numbers may be more difficult than it sounds. Although the numbers may appear random, how do you know for sure that they don't actually follow some complex, underlying pattern? ...

Apple's new privacy effort worth watching

June 22, 2016

Modern technology has presented us with something of a Faustian bargain when it comes to our privacy, but Apple thinks we should have another option.

Super quantum simulator 'entangles' hundreds of ions

June 9, 2016

Physicists at the National Institute of Standards and Technology (NIST) have "entangled" or linked together the properties of up to 219 beryllium ions (charged atoms) to create a quantum simulator. The simulator is designed ...

Recommended for you

Weird quantum effects stretch across hundreds of miles

July 19, 2016

In the world of quantum, infinitesimally small particles, weird and often logic-defying behaviors abound. Perhaps the strangest of these is the idea of superposition, in which objects can exist simultaneously in two or more ...

Light-bulb moment for stock market behaviour

July 21, 2016

University of Adelaide physicists have discovered that the timing of electronic orders on the stock market can be mathematically described in the same way as the lifetime of a light bulb.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.