Figure 5: Two-photon absorption in an atomic cladding waveguide.
From: Nanoscale light–matter interactions in atomic cladding waveguides
(a) Optical setup for measuring two-photon absorption in an atomic cladding waveguide. Mod, amplitude modulator; LIA, lock in amplifier (b) Measured transmission spectrum of the 780-nm source while being scanned by the 776-nm source (blue line), and the corresponding theoretical reference curve (green dashed line).
