Maximizing Performance of Quantum Cascade Laser-Pumped Molecular Lasers

Journal Article (Journal Article)

Quantum-cascade-laser-(QCL) pumped molecular lasers (QPMLs) have recently been introduced as a source of powerful (>1 mW) tunable (>1 THz) narrow-band (<10 kHz) continuous-wave terahertz radiation. The performance of these lasers depends critically on molecular collision physics, pump saturation, and on the design of the laser cavity. Using a validated three-level model that captures the essential collision and saturation behaviors of the QPML gas nitrous oxide (N2O), we explore how the threshold pump power and output terahertz power depend on the pump power and gas pressure, as well as on the diameter, length, and output-coupler transmissivity of a cylindrical cavity. The analysis indicates that maximum power occurs as pump saturation is minimized in a manner that depends much more sensitively on pressure than on cell diameter, length, or transmissivity. A near-optimal compact laser cavity can produce tens of milliwatts of power tunable over frequencies above 1 THz when pumped by a multiwatt QCL.

Full Text

Duke Authors

Cited Authors

  • Wang, F; Johnson, SG; Everitt, HO

Published Date

  • August 1, 2021

Published In

Volume / Issue

  • 16 / 2

Electronic International Standard Serial Number (EISSN)

  • 2331-7019

Digital Object Identifier (DOI)

  • 10.1103/PhysRevApplied.16.024010

Citation Source

  • Scopus