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تسجيل مستخدم جديدTunable RF-photonic filtering with high out-of-band rejection in silicon
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The ever-increasing demand for high speed and large bandwidth has made photonic systems a leading candidate for the next generation of telecommunication and radar technologies. The photonic platform enables high performance while maintaining a small footprint and provides a natural interface with fiber optics for signal transmission. However, producing sharp, narrow-band filters that are competitive with RF components has remained challenging. In this paper, we demonstrate all-silicon RF-photonic multi-pole filters with $sim100times$ higher spectral resolution than previously possible in silicon photonics. This enhanced performance is achieved utilizing engineered Brillouin interactions to access long-lived phonons, greatly extending the available coherence times in silicon. This Brillouin-based optomechanical system enables ultra-narrow (3.5 MHz) multi-pole response that can be tuned over a wide ($sim10$ GHz) spectral band. We accomplish this in an all-silicon optomechanical waveguide system, using CMOS compatible fabrication techniques. In addition to bringing greatly enhanced performance to silicon photonics, we demonstrate reliability and robustness, necessary to transition silicon-based optomechanical technologies from the scientific bench-top to high-impact field-deployable technologies.
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