Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Multiphonon-assisted lasing beyond the fluorescence spectrum

Abstract

Lasing typically starts from fluorescence, and the laser wavelength is therefore limited to the fluorescence spectrum of the gain material. Accessing wavelengths beyond this intrinsic emission spectrum requires emission assisted by multiphonon processes. However, this is much weaker than the fluorescence originating from direct transitions between electronic energy levels, which only involve a small number of phonons. Here, we present the realization of lasers far beyond the fluorescence spectrum in Yb-doped YCa4O(BO3)3 crystals. We selectively amplify three- to eight-phonon processes and suppress all the fewer-phonon ones, which we attribute to constructive interactions of vibrational modes from free oxygen sites. We obtain an overall spectral tuneability of 1,110–1,465 nm in five segments, each with its own configuration, corresponding to the three- to seven-phonon cases. The longest (eight-phonon) lasing wavelength can reach 1,518 nm, over 400 nm beyond the fluorescence spectrum. Our results shed light on strengthening the original weak electron–phonon–photon interaction and give rise to a search for on-demand lasers operating outside the fluorescence spectrum.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Schematic diagram of the multiphonon–electron coupled laser.
Fig. 2: Yb:YCOB crystal and laser generation.
Fig. 3: Lasing beyond the fluorescence spectrum.
Fig. 4: Mechanism of multiphonon–electron coupled lasing.

Similar content being viewed by others

Data availability

Source data are available for this paper. All other data that support the findings of this study are available from the corresponding author upon reasonable request. Source data are provided with this paper.

References

  1. Maiman, T. H. Stimulated optical radiation in ruby. Nature 187, 493–494 (1960).

    Article  ADS  Google Scholar 

  2. Sugioka, K. & Cheng, Y. Ultrafast lasers—reliable tools for advanced materials processing. Light. Sci. Appl. 3, e149 (2014).

    Article  ADS  Google Scholar 

  3. Kaushal, H. & Kaddoum, G. Optical communication in space: challenges and mitigation techniques. IEEE Commun. Surv. Tutor. 19, 57–96 (2016).

    Article  Google Scholar 

  4. Ofelt, G. S. Intensities of crystal spectra of rare-earth ions. J. Chem. Phys. 37, 511–521 (1962).

    Article  ADS  Google Scholar 

  5. Judd, B. R. Optical Absorption intensities of rare-earth ions. Phys. Rev. 127, 750–761 (1962).

    Article  ADS  Google Scholar 

  6. Hehlen, M. P., Mikhail, G. B. & Karl, W. K. 50th anniversary of the Judd–Ofelt theory: an experimentalist’s view of the formalism and its application. J. Lumin. 136, 221–239 (2013).

    Article  Google Scholar 

  7. Zhu, S., Zhu, Y. & Ming, N. Quasi-phase-matched third-harmonic generation in a quasi-periodic optical superlattice. Science 278, 843–846 (1997).

    Article  ADS  Google Scholar 

  8. Ferreira, M. S. & Wetter, N. U. Diode-side-pumped, intracavity Nd:YLF/KGW/LBO Raman laser at 573 nm for retinal photocoagulation. Opt. Lett. 46, 508–511 (2021).

    Article  ADS  Google Scholar 

  9. Khurgin, J. B., Clerici, M. & Kinsey, N. Fast and slow nonlinearities in epsilon‐near‐zero materials. Laser Photonics Rev. 14, 2000291 (2020).

    Google Scholar 

  10. Johnson, L. F., Dietz, R. E. & Guggenheim, H. J. Optical maser oscillation from Ni2+ in MgF2 involving simultaneous emission of phonons. Phys. Rev. Lett. 11, 318–320 (1963).

    Article  ADS  Google Scholar 

  11. Pohl, R. W. Electron conductivity and photochemical processes in alkali-halide crystals. Proc. Phys. Soc. 49, 3–31 (1937).

    Article  ADS  Google Scholar 

  12. Hellwege, K. H. On the fluorescence and the coupling between electron terms and crystal lattices in aqueous salts of rare earths. Ann. Phys. 40, 529–542 (1941).

    Article  Google Scholar 

  13. Alkauskas, A. et al. First-principles theory of the luminescence lineshape for the triplet transition in diamond NV centres. N. J. Phys. 16, 073026 (2014).

    Article  Google Scholar 

  14. Moulton, P. F. Tunable solid-state lasers. Proc. IEEE 80, 348–364 (1992).

    Article  ADS  Google Scholar 

  15. Sennaroglu, A. Broadly tunable Cr4+-doped solid-state lasers in the near infrared and visible. Prog. Quantum Electron. 26, 287–352 (2002).

    Article  ADS  Google Scholar 

  16. Basiev, T. T., Mirov, S. B. & Osiko, V. V. Room-temperature color center lasers. IEEE J. Quantum Elect. 24, 1052–1069 (1988).

    Article  ADS  Google Scholar 

  17. Moulton, P. F. Spectroscopic and laser characteristics of Ti:Al2O3. J. Opt. Soc. Am. B 3, 125–133 (1986).

    Article  ADS  Google Scholar 

  18. Walling, J. C. et al. Tunable alexandrite lasers. IEEE J. Quantum Elect. 16, 1302–1315 (1980).

    Article  ADS  Google Scholar 

  19. Moulton, P. F. An investigation of the Co:MgF2 laser system. IEEE J. Quantum Elect. 21, 1582–1595 (1985).

    Article  ADS  Google Scholar 

  20. Peters, R. et al. Broadly tunable high-power Yb:Lu2O3 thin disk laser with 80% slope efficiency. Opt. Express 15, 7075–7082 (2007).

    Article  ADS  Google Scholar 

  21. Gao, Z. et al. Diode-pumped self-starting mode-locked femtosecond Yb:YCa4O(BO3)3 laser. Chin. Phys. B 23, 054207 (2014).

    Article  ADS  Google Scholar 

  22. Loiko, Pavel et al. Highly efficient 2.3 µm Thulium lasers based on a high-phonon-energy crystal: evidence of vibronic-assisted emissions. J. Opt. Soc. Am. B 38, 482–495 (2021).

    Article  ADS  Google Scholar 

  23. Di Bartolo, B. Optical Interactions in Solids (World Scientific, 2010).

  24. Huang, K. & Rhys, A. Theory of light absorption and non-radiative transitions in F-centres. Proc. R. Soc. Lond. A 204, 406–423 (1950).

    Article  ADS  MATH  Google Scholar 

  25. Ellens, A. et al. Spectral-line-broadening study of the trivalent lanthanide-ion series. II. The variation of the electron–phonon coupling strength through the series. Phys. Rev. B 55, 180–186 (1997).

    Article  ADS  Google Scholar 

  26. Demirbas, U. & Baali, I. Power and efficiency scaling of diode pumped Cr:LiSAF lasers: 770–1110 nm tuning range and frequency doubling to 387–463 nm. Opt. Lett. 40, 4615–4618 (2015).

    Article  ADS  Google Scholar 

  27. Chen, P. et al. 12.3-W output power and 271-nm wavelength tunability of diode-double end-pumped Tm:CALYO laser. Opt. Laser Technol. 152, 108095 (2022).

    Article  Google Scholar 

  28. Pinto, J. F. et al. Improved Ti: sapphire laser performance with new high figure of merit crystals. IEEE J. Quantum Elect. 30, 2612–2616 (1994).

    Article  ADS  Google Scholar 

  29. Caro, P. Phonon interference in the analysis of rare earth 4fn energy level sequences. J. Less-Common Met. 126, 239–245 (1986).

    Article  Google Scholar 

  30. Kaminskii, A. A. et al. High-order stimulated Raman scattering combined with second harmonic generation in [χ(2)+χ(3)]-nonlinear LaBGeO5, β′-Gd2(MoO4)3 and Ca4Gd(BO3)3O laser host crystals under picosecond excitation. J. Raman Spectrosc. 29, 645–648 (1998).

    Article  ADS  Google Scholar 

  31. Maczka, M. et al. Lattice dynamics of Ca4GdO(BO3)3. J. Raman Spectrosc. 35, 266–273 (2004).

    Article  ADS  Google Scholar 

  32. Lupei, A. et al. Selective excitation study of Yb3+ in GdCa4O(BO3)3 and YCa4O(BO3)3. J. Phys. Condens. Matter 14, 1107–1117 (2002).

    Article  ADS  Google Scholar 

  33. Dirksen, G. J. & Blasse, G. Tetracalcium gadolinium oxoborate Ca4GdO(BO3)3 as a new host lattice for luminescent materials. J. Alloy. Compd. 191, 121–126 (1993).

    Article  Google Scholar 

  34. Blasse, G. Rare earth spectroscopy in relation to materials science. Mater. Chem. Phys. 31, 3–6 (1992).

    Article  Google Scholar 

  35. Loiko, P. et al. Watt-level europium laser at 703 nm. Opt. Lett. 46, 2702–2705 (2021).

    Article  ADS  Google Scholar 

  36. Koechner, W. & Bass, M. Solid-State Lasers (Springer-Verlag, 2003).

    Book  Google Scholar 

  37. Samuel, I. D. W. et al. How to recognize lasing. Nat. Photonics 3, 546–549 (2009).

    Article  ADS  Google Scholar 

  38. Fibrich, M. et al. Influence of temperature on Ti: sapphire spectroscopic and laser characteristics. Laser Phys. 28, 085801 (2018).

    Article  ADS  Google Scholar 

  39. Kerridge, W. R. & Damzen, M. J. Temperature effects on tunable cw alexandrite lasers under diode end-pumping. Opt. Express 26, 7771–7785 (2018).

    Article  ADS  Google Scholar 

  40. Blasse, G. Interaction between optical centers and their surroundings: an inorganic chemist’s approach. Adv. Inorg. Chem. 35, 319–402 (1990).

    Article  Google Scholar 

Download references

Acknowledgements

This work was supported by the National Key Research and Development Program of China (grant nos. 2021YFB3601504 and 2021YFA0717800) and the Natural Science Foundation of China (grant nos. 52025021, 92163207, 51890863 and 52002220). F.L. acknowledges the support of Future Plans of Young Scholars at Shandong University. F.L. acknowledges H. Si and Y. Cheng for support with laser measurements. F.L. acknowledges W. Liu, J. Feng, and G. Zhang for crystal growth of Yb:La2CaB10O19, Gd:Na3La9O3(BO3)8, Li3K9Gd3(BO3)7 and Rb7SrGd2(B5O12)3.

Author information

Authors and Affiliations

Authors

Contributions

H.Y. and H.Z. conceived and supervised the project. F.L., C.H. and D.L. performed the laser experiments and wrote the manuscript. Q.F. performed some laser experiments. Y.F. performed some spectral measurements. Y.-F.C. provided helpful suggestions and theoretical analysis on the electron–phonon coupling effect. All authors contributed to the discussion and the preparation of the manuscript.

Corresponding authors

Correspondence to Haohai Yu, Huaijin Zhang or Yan-Feng Chen.

Ethics declarations

Competing interests

The authors declare no competing interests.

Peer review

Peer review information

Nature Physics thanks Anton Husakou and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Figs. 1–27, discussion and Tables 1–5.

Reporting summary

Source data

Source Data Fig. 3

Laser wavelength and laser power.

Source Data Fig. 4

Raman spectrum and phonon dispersion.

Rights and permissions

Springer Nature or its licensor holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Liang, F., He, C., Lu, D. et al. Multiphonon-assisted lasing beyond the fluorescence spectrum. Nat. Phys. 18, 1312–1316 (2022). https://doi.org/10.1038/s41567-022-01748-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41567-022-01748-z

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing