Institut National de la Recherche Scientifique (INRS)-Energie, Matériaux et Télécommunications, Montréal, Québec, Canada H5A 1K6.
1] Institut National de la Recherche Scientifique (INRS)-Energie, Matériaux et Télécommunications, Montréal, Québec, Canada H5A 1K6 [2] Department of Physics and Astronomy, Augustana College, Rock Island, Illinois 61201, USA.
Nat Commun. 2014 Oct 16;5:5163. doi: 10.1038/ncomms6163.
Amplification of signal intensity is essential for initiating physical processes, diagnostics, sensing, communications and measurement. During traditional amplification, the signal is amplified by multiplying the signal carriers through an active gain process, requiring the use of an external power source. In addition, the signal is degraded by noise and distortions that typically accompany active gain processes. We show noiseless intensity amplification of repetitive optical pulse waveforms with gain from 2 to ~20 without using active gain. The proposed method uses a dispersion-induced temporal self-imaging (Talbot) effect to redistribute and coherently accumulate energy of the original repetitive waveforms into fewer replica waveforms. In addition, we show how our passive amplifier performs a real-time average of the wave-train to reduce its original noise fluctuation, as well as enhances the extinction ratio of pulses to stand above the noise floor. Our technique is applicable to repetitive waveforms in any spectral region or wave system.
信号强度的放大对于启动物理过程、诊断、传感、通信和测量至关重要。在传统的放大中，通过有源增益过程对信号载波进行乘法运算来放大信号，这需要使用外部电源。此外，信号会因通常伴随有源增益过程的噪声和失真而劣化。我们展示了无需使用有源增益即可实现从 2 到~20 的重复光脉冲波形的无噪声强度放大。所提出的方法利用色散诱导的时域自成像（Talbot）效应将原始重复波形的能量重新分配并相干地累积到较少的复制品波形中。此外，我们展示了我们的无源放大器如何执行波列的实时平均以降低其原始噪声波动，以及如何增强脉冲的消光比以高于噪声底。我们的技术适用于任何光谱区域或波系统中的重复波形。
