Figure 1
From: Absolute spectroscopy near 7.8 μm with a comb-locked extended-cavity quantum-cascade-laser
Experimental setup. Green line: EC-QCL optical path. Orange line: Tm-comb optical path. Grey dashed lines: electrical links. PBS: Polarizing beam splitter. PD: photodetector, PZT: Piezo actuator. OI: optical isolator. SC: supercontinuum. ZGP: Zinc-Germanium Phosphide. HWP: half wave plate. BC: beam combiner. OF: optical fiber coupler. BD: balance detector. LO: local oscillator. AOFS: acousto-optic frequency shifter. HV: high voltage amplifier. VCO: voltage controlled oscillator.
