Third Harmonic Generation in a Quantum Cascade Laser

1
Third Harmonic Generation in a Quantum Cascade
Laser
APS March Meeting March 22, 2004

• Trinesha S. Mosely, Alexey Belyanin, Claire
  Gmachl, Deborah L. Sivco, Milton L. Peabody, and
  Alfred Y. Cho
• Bell Laboratories, Lucent Technologies, Murray
  Hill, NJ, 07974, USA
• Department of Physics, Texas AM University,
  College Station, TX 77843
• Present address Rice University, Houston, TX
  77005
• Present address Princeton University,
  Princeton, NJ 08544
• Supported by DARPA / US ARO and TAMU TITF
  Initiative and the Office of Naval Research

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What is a Quantum Cascade Laser?

• Mid-infrared semiconductor injection laser
• based on optical intersubband
  transitions and cascading scheme
• Wavelength Agility
• wavelength emission determined by layer
  thicknesses not
• material chemistry (3.5 mm - 24 mm )
• Demonstrated applications in mid-IR gas sensing
• High optical power
• cascading reuses electrons (1 - 100 x) 2 W
  peak, 0.5 W cw

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Motivation

• Monolithically integrated nonlinearity
• Sub-3 micron emission
• Free-space optical wireless communications
• Nonlinear light generation
• Second harmonic generation
• Third harmonic generation

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Second Harmonic Generation
Laser Nonlinear Crystal
Resonant Intersubband Nonlinearity
1Oana Malis, Alexey Belyanin, Claire Gmachl,
Deborah L. Sivco, Milton L. Peabody, A. Michael
Sergent, and Alfred Y. Cho Improvement of
second-harmonic generation in quantum-cascade
lasers with true phase-matching Accepted for
publication in Appl. Phys. Lett. 2004
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Quantum cascade laser with monolithically
integrated nonlinearity for third harmonic
generation
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Monolithically Integrated Nonlinearity Idea
Active region functions simultaneously as a
fundamental pump and nonlinear light source
Laser Nonlinear Crystal
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Monolithically Integrated NonlinearityDesign
Large dipole moment product z32 z32 z32
z32 Near-resonance energy spacings ?Eij
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Monolithically Integrated Nonlinearity Single
Device Spectra
SHG (5.4 ?m)?
Fundamental Emission (11.1 ?m)?
THG (3.7 ?m)?
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Monolithically Integrated Nonlinearity Results
Nonlinear results ?(3) 7x10-8 esu Power 30-
50 nW
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Monolithically Integrated Nonlinearity
Conclusions

• Monolithically integrated nonlinearity in QC
  active regions
• Linear and nonlinear light generation from single
  device
• THG
• Outlook
• Phase-matching