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Femtosecond pulses from a mid-infrared quantum cascade laser

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Abstract

The quantum cascade laser has evolved to be a compact, powerful source of coherent mid-infrared light; however, its fast gain dynamics strongly restricts the formation of ultrashort pulses. As such, the shortest pulses reported so far were limited to a few picoseconds with some hundreds of milliwatts of peak power, strongly narrowing their applicability for time-resolved and nonlinear experiments. Here we demonstrate an approach capable of producing near-transform-limited subpicosecond pulses with several watts of peak power. Starting from a frequency-modulated phase-locked state, ultrashort high-peak-power pulses are generated via spectral filtering, gain modulation-induced spectral broadening and external pulse compression. We assess their temporal nature by means of a novel asynchronous sampling method, coherent beat note interferometry and interferometric autocorrelation. These results open new pathways for nonlinear physics in the mid-infrared.

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Fig. 1: Diffraction grating compressor.
Fig. 2: Complex comb spectrum and coherence before and after pulse compression as measured by SWIFTS.
Fig. 3: Asynchronous upconversion sampling.
Fig. 4: Compressed and uncompressed QCL intensity profile as measured by ASUPS.
Fig. 5: Compressed QCL pulses as measured by IAC.
Fig. 6: Shortest compressed QCL pulses.

Data availability

The measurement data that support the plots within this paper are available at https://www.research-collection.ethz.ch/handle/20.500.11850/504681 and from the corresponding author on reasonable request. Data that support the findings in this article are also available in the ETH Research Collection43.

Code availability

The analysis codes will be made available on reasonable request.

Change history

  • 24 November 2021

    In the HTML version of this Article published online, the copyright information was in error; the copyright information has now been corrected.

References

  1. 1.

    Haus, H. A. Mode-locking of lasers. IEEE J. Sel. Top. Quantum Electronics 6, 1173–1185 (2000).

    ADS  Google Scholar 

  2. 2.

    Morgner, U. et al. Sub-two-cycle pulses from a Kerr-lens mode-locked Ti:sapphire laser. Opt. Lett. 24, 411–413 (1999).

    ADS  Google Scholar 

  3. 3.

    Sutter, D. H. et al. Semiconductor saturable-absorber mirror-assisted Kerr-lens mode-locked Ti:sapphire laser producing pulses in the two-cycle regime. Opt. Lett. 24, 631–633 (1999).

    ADS  Google Scholar 

  4. 4.

    Huber, R. et al. How many-particle interactions develop after ultrafast excitation of an electron-hole plasma. Nature 414, 286–289 (2001).

    ADS  Google Scholar 

  5. 5.

    Torre, R., Bartolini, P. & Righini, R. Structural relaxation in supercooled water by time-resolved spectroscopy. Nature 428, 296–299 (2004).

    ADS  Google Scholar 

  6. 6.

    Udem, T., Holzwarth, R. & Hänsch, T. W. Optical frequency metrology. Nature 416, 233–237 (2002).

    ADS  Google Scholar 

  7. 7.

    Pires, H., Baudisch, M., Sanchez, D., Hemmer, M. & Biegert, J. Ultrashort pulse generation in the mid-IR. Prog. Quantum Electron. 43, 1–30 (2015).

    ADS  Google Scholar 

  8. 8.

    Cao, Q., Kärtner, F. X. & Chang, G. Towards high power longwave mid-IR frequency combs: power scalability of high repetition-rate difference-frequency generation. Opt. Express 28, 1369–1384 (2020).

    ADS  Google Scholar 

  9. 9.

    Faist, J. et al. Quantum cascade laser. Science 264, 553–556 (1994).

    ADS  Google Scholar 

  10. 10.

    Jouy, P. et al. Dual comb operation of λ ~ 8.2 μm quantum cascade laser frequency comb with 1 W optical power. Appl. Phys. Lett. 111, 141102 (2017).

    ADS  Google Scholar 

  11. 11.

    Schwarz, B. et al. Watt-level continuous-wave emission from a bifunctional quantum cascade laser/detector. ACS Photon. 4, 1225–1231 (2017).

    Google Scholar 

  12. 12.

    Hugi, A., Villares, G., Blaser, S., Liu, H. C. & Faist, J. Mid-infrared frequency comb based on a quantum cascade laser. Nature 492, 229–233 (2012).

    ADS  Google Scholar 

  13. 13.

    Singleton, M., Jouy, P., Beck, M. & Faist, J. Evidence of linear chirp in mid-infrared quantum cascade lasers. Optica 5, 948–953 (2018).

    ADS  Google Scholar 

  14. 14.

    Choi, H. et al. Gain recovery dynamics and photon-driven transport in quantum cascade lasers. Phys. Rev. Lett. 100, 167401 (2008).

    ADS  Google Scholar 

  15. 15.

    Wang, C. Y. et al. Mode-locked pulses from mid-infrared quantum cascade lasers. Opt. Express 17, 12929–12943 (2009).

    ADS  Google Scholar 

  16. 16.

    Revin, D. G., Hemingway, M., Wang, Y., Cockburn, J. W. & Belyanin, A. Active mode locking of quantum cascade lasers in an external ring cavity. Nat. Commun. 7, 11440 (2016).

    ADS  Google Scholar 

  17. 17.

    Hillbrand, J. et al. Mode-locked short pulses from an 8 μm wavelength semiconductor laser. Nat. Commun. 11, 5788 (2020).

    ADS  Google Scholar 

  18. 18.

    Barbieri, S. et al. Coherent sampling of active mode-locked terahertz quantum cascade lasers and frequency synthesis. Nat. Photon. 5, 306–313 (2011).

    ADS  Google Scholar 

  19. 19.

    Wang, F. et al. Generating ultrafast pulses of light from quantum cascade lasers. Optica 2, 944–949 (2015).

    ADS  Google Scholar 

  20. 20.

    Wang, F. et al. Short terahertz pulse generation from a dispersion compensated modelocked semiconductor laser. Laser Photon. Rev. 11, 1700013 (2017).

    ADS  Google Scholar 

  21. 21.

    Hillbrand, J., Andrews, A. M., Detz, H., Strasser, G. & Schwarz, B. Coherent injection locking of quantum cascade laser frequency combs. Nat. Photon. 13, 101–104 (2019).

    ADS  Google Scholar 

  22. 22.

    Cappelli, F. et al. Retrieval of phase relation and emission profile of quantum cascade laser frequency combs. Nat. Photon. 13, 562–568 (2019).

    ADS  Google Scholar 

  23. 23.

    Opačak, N. & Schwarz, B. Theory of frequency-modulated combs in lasers with spatial hole burning, dispersion, and Kerr nonlinearity. Phys. Rev. Lett. 123, 243902 (2019).

    ADS  Google Scholar 

  24. 24.

    Burghoff, D. Unraveling the origin of frequency modulated combs using active cavity mean-field theory. Optica 7, 1781–1787 (2020).

    ADS  Google Scholar 

  25. 25.

    Chinn, S. & Swanson, E. Passive FM locking and pulse generation from 980-nm strained-quantum-well Fabry-Perot lasers. IEEE Photon. Technol. Lett. 5, 969–971 (1993).

    ADS  Google Scholar 

  26. 26.

    Sato, K. Optical pulse generation using Fabry-Pe/spl acute/rot lasers under continuous-wave operation. IEEE J. Sel. Top. Quantum Electron. 9, 1288–1293 (2003).

    ADS  Google Scholar 

  27. 27.

    Rosales, R. et al. High performance mode locking characteristics of single section quantum dash lasers. Opt. Express 20, 8649–8657 (2012).

    ADS  Google Scholar 

  28. 28.

    Martinez, O. 3000 Times grating compressor with positive group velocity dispersion: application to fiber compensation in 1.3–1.6 μm region. IEEE J. Quantum Electron. 23, 59–64 (1987).

    ADS  Google Scholar 

  29. 29.

    Singleton, M., Beck, M. & Faist, J. Pulses from a mid-infrared quantum cascade laser frequency comb using an external compressor. J. Opt. Soc. Am. B 36, 1676–1683 (2019).

    ADS  Google Scholar 

  30. 30.

    Gellie, P. et al. Injection-locking of terahertz quantum cascade lasers up to 35 GHz using RF amplitude modulation. Opt. Express 18, 20799–20816 (2010).

    ADS  Google Scholar 

  31. 31.

    Burghoff, D. et al. Terahertz laser frequency combs. Nat. Photon. 8, 462–467 (2014).

    ADS  Google Scholar 

  32. 32.

    Burghoff, D. et al. Evaluating the coherence and time-domain profile of quantum cascade laser frequency combs. Opt. Express 23, 1190–1202 (2015).

    ADS  Google Scholar 

  33. 33.

    Takara, H., Kawanishi, S., Yamabayashi, Y. & Saruwataris, M. An ultrahigh-speed optical waveform measurement method based on optical sampling with sum-frequency generation. Electron. Commun. Jpn 76, 1–11 (1993).

    Google Scholar 

  34. 34.

    Argence, B. et al. Quantum cascade laser frequency stabilization at the sub-Hz level. Nat. Photon. 9, 456–460 (2015).

    ADS  Google Scholar 

  35. 35.

    Karstad, K. et al. Detection of mid-IR radiation by sum frequency generation for free space optical communication. Optics Lasers Eng. 43, 537–544 (2005).

    ADS  Google Scholar 

  36. 36.

    Rodwell, M. J. W., Weingarten, K. J., Bloom, D. M., Baer, T. & Kolner, B. H. Reduction of timing fluctuations in a mode-locked Nd:YAG laser by electronic feedback. Opt. Lett. 11, 638–640 (1986).

    ADS  Google Scholar 

  37. 37.

    Piccardo, M. et al. Frequency-modulated combs obey a variational principle. Phys. Rev. Lett. 122, 253901 (2019).

    ADS  Google Scholar 

  38. 38.

    Boiko, D. L. et al. Mid-infrared two photon absorption sensitivity of commercial detectors. Appl. Phys. Lett. 111, 171102 (2017).

    ADS  Google Scholar 

  39. 39.

    Kapsalidis, F. et al. Mid-infrared quantum cascade laser frequency combs with a microstrip-like line waveguide geometry. Appl. Phys. Lett. 118, 071101 (2021).

    ADS  Google Scholar 

  40. 40.

    Strickland, D. & Mourou, G. Compression of amplified chirped optical pulses. Opt. Commun. 56, 219–221 (1985).

    ADS  Google Scholar 

  41. 41.

    Benedikovic, D. et al. Dispersion control of silicon nanophotonic waveguides using sub-wavelength grating metamaterials in near- and mid-ir wavelengths. Opt. Express 25, 19468–19478 (2017).

    ADS  Google Scholar 

  42. 42.

    Cai, H., Liu, S., Lalanne, E. & Johnson, A. M. Investigation of giant Kerr nonlinearity in quantum cascade lasers using mid-infrared femtosecond pulses. Appl. Phys. Lett. 106, 051102 (2015).

    ADS  Google Scholar 

  43. 43.

    Täschler, P. ETH Research Collection (ETH, 2021); https://www.research-collection.ethz.ch/handle/20.500.11850/504681

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Acknowledgements

This work was supported by the BRIDGE program, funded by the Swiss National Science Foundation and Innosuisse, in the scope of the CombTrace (no. 176584; P.T., M.Bertrand, F.K.) project. Further financial support was provided by the Swiss National Science Foundation (no. 165639; M.S., P.J.) and the European Union’s Horizon 2020 research and innovation program Qombs (no. 820419; B.S.). We would like to gratefully thank J. Hillbrand for helpful advice and discussion while conducting the experiments and for proofreading the manuscript. Moreover, we express gratitude to S. Markmann and A. Forrer for their careful reading of the paper, S. Wang for his preliminary work on ASUPS and R. Wang for providing QCLs in an early stage of the work. We thank E. Gini of the FIRST—Center for Micro- and Nanoscience for the MOVPE regrowths.

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Contributions

P.T. built the upconversion, SWIFTS and autocorrelation set-up, performed the experiments and wrote the manuscript with editorial input from M.Bertrand, B.S. and J.F. M.Bertrand characterized the normal buried heterostructure device (LIV, optical spectra) used for this publication, performed preliminary IAC experiments and helped with the set-up of the radiofrequency-optimized device. B.S. was involved in the SWIFTS analysis, characterized the radiofrequency-optimized laser (LIV, optical spectra, beat note), helped with its set-up and performed preliminary strong microwave modulation experiments. M.S. dimensioned the grating compressor. P.J. and F.K. processed the QCLs used in this work. M.Beck was responsible for MBE growth. J.F. supervised this work.

Corresponding authors

Correspondence to Philipp Täschler or Jérôme Faist.

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Peer review informationNature Photonics thanks Stefano Barbieri, Benedikt Schwarz and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary Sections 1–5 and Figs. 1–5.

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Täschler, P., Bertrand, M., Schneider, B. et al. Femtosecond pulses from a mid-infrared quantum cascade laser. Nat. Photon. 15, 919–924 (2021). https://doi.org/10.1038/s41566-021-00894-9

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