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arXiv · 2504.20957

A Quieter State of Charge -- Ultra-Low-Noise Collective Current in Charge-Density-Wave Nanowires

Abstract

Electronic flicker noise limits phase stability in communication systems, reduces the sensitivity and selectivity of sensors, and degrades coherence in quantum devices. There is a strong need for unconventional materials and strategies for achieving ultra-low-noise performance in nanoscale and quantum electronics. Here, we demonstrate that in nanowires of the quasi-one-dimensional, fully gapped charge-density-wave material (TaSe4)2I, low-frequency electronic noise is suppressed below the limit of thermalized charge carriers in passive resistors. When the current is dominated by the sliding Frohlich condensate, the normalized noise spectral density decreases linearly with current, I -- a striking departure from the constant value observed in conventional conductors. No residual minimum noise level is reached for the current of the electron-lattice condensate in (TaSe4)2I nanowires. Repeating the measurements for another charge-density wave conductor, NbS3-II, we found a similar reduction below the normal electron limit at room temperature. Our findings signal intrinsically lower current fluctuations within a correlated electron transport regime.

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Subhajit Ghosh, Nicholas Sesing, Tina Salguero, Sergey Rumyantsev, Roger K. Lake, Alexander A. Balandin. 2026-01-17. A Quieter State of Charge -- Ultra-Low-Noise Collective Current in Charge-Density-Wave Nanowires. https://doi.org/10.1038/s41467-025-67567-x

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