Fig. 3: Broadband spectrum characterization.
From: Compact and high-resolution spectrometer via Brillouin integrated circuits
a Separate spectral line response with different pump wavelengths, with an RF drive power is 20 mW. Inset: the relationship between the reflected optical power and the input power; Dispersion relationship between the beat frequency of the output light and the input optical wavelength. The slope is 6.03 MHz/nm. b Top: RF response spectrum with two pump lasers at 1550.5 nm and 1550 nm. The red line represents a double-Lorentz fitting for the measured data, which is the sum of two Lorentz distributions displayed in yellow. Bottom: Reconstructed optical spectrum. c We use a standard commercial dense wavelength division multiplexing (DWDM) as a filter to generate the spectrum by tuning the spontaneous radiation of our EDFA without any laser input. The blue line represents the reflection power from our device via sweeping microwave frequency and detected by a PD directly, and the orange line comes from a commercial spectrometer.
