Ultrahigh Resolution Spectroscopy Across the Visible to Infrared Spectrum Using Multi-Mode Interference in a Compact Tapered Fiber

摘要: Optical spectroscopy is a fundamental tool in numerous areas of science and technology. Much effort has focused on miniaturizing spectrometers, but thus far at the cost high spectral resolution broad operating range. Here, we describe compact spectrometer without this trade-off. The device relies imaging multi-mode interference from leaky modes along highly multimode tapered optical fiber, resulting spectrally distinguishable images that form basis for reconstructing an incident light spectrum. This fiber enables acquisition broadband spectra single camera exposure with measured 40 pm visible spectrum 10 infrared spectrum, which are comparable to performance grating spectrometers. Spectroscopy 500 nm 1600 demonstrated, though operation across entire transparency window silica fibers possible. Multimode suitable variety geometries, including planar waveguides range transparent materials. We anticipate technique will greatly expand availability high-performance wide applications.