High performance quantum cascade laser frequency combs at λ ∼ 6 μm based on plasmon-enhanced dispersion compensation

Optics Express
Sargis HakobyanAntoine Muller

Abstract

We demonstrate quantum cascade laser (QCL) optical frequency combs emitting at λ ∼ 6 μm. A 5.5 μm-wide, 4.5 mm-long laser exhibits comb operation from -20 °C up to 50 °C. A maximum output power of 300 mW is achieved at 50 °C showing a robustness of the system. The laser output spectrum is ∼80 cm-1 wide at the maximum current, with a mode spacing of 0.334 cm-1, resulting in a total of 240 modes with an average power of 0.8 mW per mode. To achieve frequency comb operation, a plasmonic-waveguide approach is utilized. A thin, highly-doped indium phosphide (InP) layer is inserted in the top cladding design to compensate the positive dispersion of the system (material and waveguide). This approach can be further exploited to design QCL combs at even shorter wavelengths, down to 4 μm. Different ridge widths between 2.8 and 5.5 μm have been fabricated and characterized. All of the devices exhibit frequency comb operation. These observations demonstrate that the plasmonic-waveguide is a robust and reliable method for dispersion compensation of a semiconductor laser systems to achieve frequency comb operation.

References

Jul 14, 2001·Science·S A DiddamsD J Wineland
Dec 22, 2007·Nature·P Del'HayeT J Kippenberg
Sep 6, 2008·Science·Tilo SteinmetzThomas Udem
Apr 30, 2011·Science·T J KippenbergS A Diddams
Sep 22, 2011·Optics Express·Richard MauliniC Kumar N Patel
Jul 6, 2014·Nature Protocols·Matthew J BakerFrancis L Martin
Oct 14, 2014·Nature Communications·Gustavo VillaresJérôme Faist
Apr 4, 2015·Optics Express·Sandro M LinkUrsula Keller
Apr 14, 2018·Optics Letters·Johannes HillbrandJérôme Faist

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