标题： 更安静的荷电状态——电荷密度波纳米线中的超低噪声集体电流 显示英文标题

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

摘要： 在准一维（准1D）电荷密度波（CDW）系统中，电流由正常电子和与CDW滑动相关的集体电子-晶格凝聚电流组成。 虽然在实际材料中实现无耗散的Frohlich电流是不可能的，但可以设想一个重要的相关目标，即达到电子输运区域，在该区域由于电子-晶格凝聚电流的集体强关联性质，电子噪声受到抑制。 在此我们报告，在全能隙CDW材料（TaSe4）2I的纳米线中，低频电子噪声低于被动电阻器中热化电荷载流子的极限。 当电流主要由滑动的Frohlich凝聚体主导时，归一化的噪声谱密度随电流线性下降——这与传统导体中观察到的恒定值形成鲜明对比。 这一发现表明在关联输运区域内电流波动本质上较低。 由于CDW去钉扎阈值的波动导致的主要噪声源是外在的，由局部钉扎凝聚体的晶格缺陷引起。 一旦偏置电压远超过阈值并建立了滑动模式，归一化的噪声就会低于正常电子的噪声。 对于凝聚体的电流，没有观察到残余的最小噪声水平。 由于闪烁噪声限制了通信系统的相位稳定性，降低了传感器的灵敏度和选择性，并损害了量子器件的相干性，我们的发现引入了一种根本性的新策略，利用强关联材料在纳米尺度和量子电子学中实现超低噪声性能。 显示英文摘要

摘要： In quasi-one-dimensional (quasi-1D) charge-density-wave (CDW) systems, electric current comprises normal electrons and a collective, electron-lattice condensate current associated with CDW sliding. While achieving the dissipation-less Frohlich current of the sliding condensate is impossible in real materials, one can imagine an important related target, namely reaching the electron transport regime where electronic noise is inhibited due to the collective, strongly-correlated nature of the electron-lattice condensate current. Here we report that in nanowires of the fully-gapped CDW 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 -- a striking departure from the constant value observed in conventional conductors. This discovery signals intrinsically lower current fluctuations within a correlated transport regime. The dominant noise source due to fluctuations in the CDW depinning threshold is extrinsic and caused by lattice imperfections that locally pin the condensate. Once the bias voltage is well past threshold and the sliding mode is established, the normalized noise drops below the noise of normal electrons. No residual minimum noise level is observed for the current of the condensate. Since flicker noise limits phase stability in communication systems, reduces the sensitivity and selectivity of sensors, and degrades coherence in quantum devices, our discovery introduces a fundamentally new strategy for achieving ultra-low-noise performance in nanoscale and quantum electronics using strongly correlated materials.