Fig. 3: High gain Er:TFLN waveguide amplifier.
From: Unifying optical gain and electro-optical dynamics in Er-doped thin-film lithium niobate platform
a Left panel, experimental setup. WDM wavelength division multiplexer, PC Polarization controller, Att. Attenuator, OSA Optical spectrometer analyzer, PM power meter. Right panel, optical image of an Er:TFLN chip under optical pumping of 115 mW, butt-coupled with fibers. The green light emission results from the second-order cooperative upconversion process upon intense optical pumping. b Optical spectra of output signals from the pumped amplifier, when the off-chip input signal power is −39.6 dBm. c Measured internal net gain (blue dots) at 1531.7 nm with different pump power upon 1480 nm pumping; d Measured internal net gain with different wavelength (fit by cubic spline interpolation). e Optical spectra of the input signal and the amplified signal under a high off-chip input signal power of −1 dBm.
