Researchers Discover How to Dampen Electronic Noise Using Nanowires
hubie writes:
That low-frequency fuzz that can bedevil cellphone calls has to do with how electrons move through and interact in materials at the smallest scale. The electronic flicker noise is often caused by interruptions in the flow of electrons by various scattering processes in the metals that conduct them.
The same sort of noise hampers the detecting powers of advanced sensors. It also creates hurdles for the development of quantum computers - devices expected to yield unbreakable cybersecurity, process large-scale calculations and simulate nature in ways that are currently impossible.
A much quieter, brighter future may be on the way for these technologies, thanks to a new study led by UCLA. The research team demonstrated prototype devices that, above a certain voltage, conducted electricity with lower noise than the normal flow of electrons.
These experimental devices used unconventional materials to form nanowires, ribbons so thin that it would take a thousand or more to match the width of a strand of hair. In contrast to conventional electronics - in which noise levels tend to remain constant - the nanowires displayed a surprising property: Noise dropped as the electrical current increased.
The behavior of the materials was driven by a quantum phenomenon in which electrons move in concert with phonons, temperature-driven vibrations that can cause flicker noise. Importantly, one of the materials in the study dampened noise at room temperature and above.
"Normally we think about phonons as the bad guys that are scattering electrons," said corresponding author Alexander Balandin, holder of the Fang Lu Endowed Chair in Engineering at the UCLA Samueli School of Engineering, distinguished professor of materials science and engineering and a member of the California NanoSystems Institute at UCLA (CNSI). "In this particular case, we found the phonons allowed electrons to jointly move along. This weird, unique property with respect to noise could allow us to improve signal-to-noise ratio."
When voltage is applied to a metallic wire, electrons travel under the action of the electric field, constantly being bumped off-path by phonons and various defects in materials, which results in noisy current. The researchers took advantage of an additional mode for electrons to move, under very specific circumstances induced by the counterintuitive rules of quantum mechanics. In this mode, electrons tend to clump together in periodic patterns that are enabled by interactions with phonons and largely synchronized with phonons.
By analogy, electrons can be pictured as surfers traveling the ocean of a conducting material, with waves of phonons flowing through it.
In the usual mode, electrons act like newbie surfers, occasionally getting knocked off their boards by phonon waves. Electrons in the quantum-based mode are like expert surfers, catching phonon waves and using their energy to move along smoothly.
With the motion of phonons and electrons so closely connected, the materials that unlock expert-surfer mode are called "strongly correlated materials."
[...] Balandin envisions a future in which strongly correlated materials can be used as conductors for connecting components on computer chips. He thinks these materials may even support a fundamental change in circuit architecture.
"All good things come to an end," he said. "With the demand for high-end, high-power computation for artificial intelligence, we have to look at materials that, 10-plus years from now, can give us an alternative means for sending electrical signals and processing them."
The researchers plan to further investigate the materials from this study, while also seeking other materials that carry charge density waves even more efficiently at room temperature.
"Perhaps there are materials that are even better," Balandin said. "The search is on."
Journal Reference: Ghosh, S., Sesing, N., Nataj, Z.E. et al. A quieter state of charge and ultra-low-noise of the collective current in quasi-1D charge-density-wave nanowires. Nat Commun 17, 116 (2026). https://doi.org/10.1038/s41467-025-67567-x
Read more of this story at SoylentNews.