Letter

The mode-locking transition of random lasers

Received:
Accepted:
Published online:

Abstract

The discovery of the spontaneous mode-locking of lasers1,2, that is, the self-starting synchronous oscillation of electromagnetic modes in a cavity, has been a milestone of photonics allowing the realization of oscillators delivering ultrashort pulses. This process is so far known to occur only in standard ordered lasers and only in the presence of a specific device (the saturable absorber). We engineer a mode-selective pumping of a random laser formed by a self-assembled cluster of nanometric particles. We show that the random laser can be continuously driven from a configuration exhibiting weakly interacting electromagnetic resonances4,5 to a regime of collectively oscillating strongly interacting modes6,7. This phenomenon, which opens the way to the development of a new generation of miniaturized and all-optically controlled light sources, may be explained as the first evidence of spontaneous mode-locking in disordered resonators.

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References

  1. 1.

    Mode-locking of lasers. IEEE J. Sel. Top. Quantum Electron. 6, 1173–1185 (2000).

  2. 2.

    Mode-locked soliton lasers. SIAM Rev. 48, 629–678 (2006).

  3. 3.

    The physics and applications of random lasers. Nature Phys. 4, 359–367 (2008).

  4. 4.

    Random laser action in semiconductor powder. Phys. Rev. Lett. 82, 2278–2281 (1999).

  5. 5.

    , , & Spatial extent of random laser modes. Phys. Rev. Lett. 98, 143901 (2007).

  6. 6.

    Generation of light by a scattering medium with negative resonance absorption. Zh. Eksp. Teor. Fiz. 53, 1442–1447 (1967).

  7. 7.

    , , & Laser action in strongly scattering media. Nature 368, 436–438 (1994).

  8. 8.

    , , & Threshold of a random laser with cold atoms. Phys. Rev. Lett. 102, 173903 (2009).

  9. 9.

    , , & Chaotic behavior of a random laser with static disorder. Phys. Rev. A 76, 033807 (2007).

  10. 10.

    , , & Statistical regimes of random laser fluctuations. Phys. Rev. A 75, 063820 (2007).

  11. 11.

    , , , & Phase diagram and complexity of mode-locked lasers: from order to disorder. Phys. Rev. Lett. 102, 083901 (2009).

  12. 12.

    , , , & Condensation in disordered lasers: theory, 3d + 1 simulations, and experiments. Phys. Rev. Lett. 101, 143901 (2008).

  13. 13.

    , , , & Generation of spatially incoherent short pulses in laser-pumped neodymium stoichiometric crystals and powders. J. Opt. Soc. Am. B 10, 2358–2363 (1993).

  14. 14.

    & Light diffusion with gain and random lasers. Phys. Rev. E 54, 4256–4265 (1996).

  15. 15.

    , & Quantitative analysis of several random lasers. Opt. Commun. 278, 110–113 (2007).

  16. 16.

    & Dynamic light diffusion, Anderson localization and lasing in disordered inverted opals: 3d ab-initio Maxwell–Bloch computation. Nature Phys. 4, 794–798 (2008).

  17. 17.

    Spatial confinement of laser light in active random media. Phys. Rev. Lett. 84, 5584–5587 (2000).

  18. 18.

    Co-existence of strongly and weakly localized random laser modes. Nature Photon. 3, 279–282 (2009).

  19. 19.

    , , & Strong interactions in multimode random lasers. Science 320, 643–646 (2008).

  20. 20.

    & Phase transition theory of many-mode ordering and pulse formation in lasers. Phys. Rev. Lett. 89, 103901 (2002).

  21. 21.

    & Condensation in Hamiltonian parametric wave interaction. Phys. Rev. Lett. 92, 103901 (2004).

  22. 22.

    , , & Experimental studies on the mode structure of random lasers. Phys. Rev. A 81, 043830 (2010).

  23. 23.

    , , , & Time-resolved studies of stimulated emission from colloidal dye solutions. Opt. Lett. 21, 450–452 (1996).

  24. 24.

    , & Breakdown of diffusion in dynamics of extended waves in mesoscopic media. Phys. Rev. Lett. 90, 203903 (2003).

  25. 25.

    , , , & Mode repulsion and mode coupling in random lasers. Phys. Rev. B 67, 161101 (2003).

  26. 26.

    , , & Spatial extent of random laser modes. Phys. Rev. Lett. 98, 143901 (2007).

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Acknowledgements

This work was supported by ERC grant FP7/2007-2013 no. 201766; CINECA; EU FP7 NoE Nanophotonics4Enery grant no. 248855; the Spanish MICINN CSD2007-0046 (Nanolight.es); MAT2009-07841 (GLUSFA) and Comunidad de Madrid S2009/MAT-1756 (PHAMA).

Author information

Affiliations

  1. Instituto de Ciencia de Materiales de Madrid (CSIC) and Unidad Asociada CSIC-UVigo, Calle Sor Juana Inés de la Cruz 3, 28049 Madrid, Spain

    • Marco Leonetti
    •  & Cefe Lopez
  2. Dep. Molecular Medicine and CNR-ISC Dep. Physics, University Sapienza, P.le Aldo Moro 5, I-00185, Rome, Italy

    • Claudio Conti

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Contributions

All authors contributed equally to the work presented in this Letter.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Cefe Lopez.

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