Observing chaos for quantum-dot microlasers with external feedback.

Chaos presents a striking and fascinating phenomenon of nonlinear systems. A common aspect of such systems is the presence of feedback that couples the output signal partially back to the input. Feedback coupling can be well controlled in optoelectronic devices such as conventional semiconductor lasers that provide bench-top platforms for the study of chaotic behaviour and high bit rate random number generation. Here we experimentally demonstrate that chaos can be observed for quantum-dot microlasers operating close to the quantum limit at nW output powers. Applying self-feedback to a quantum-dot microlaser results in a dramatic change in the photon statistics wherein strong, super-thermal photon bunching is indicative of random-intensity fluctuations associated with the spiked emission of light. Our experiments reveal that gain competition of few quantum dots in the active layer enhances the influence of self-feedback and will open up new avenues for the study of chaos in quantum systems.

[1]  D. Bouwmeester,et al.  Self-tuned quantum dot gain in photonic crystal lasers. , 2005, Physical review letters.

[2]  Noam Gross,et al.  TE-TM coupled mode dynamics in a semiconductor laser subject to feedback with variably rotated polarization , 2009 .

[3]  Y. Ota,et al.  Laser oscillation in a strongly coupled single-quantum-dot–nanocavity system , 2009, 0905.3063.

[4]  G. Solomon,et al.  Influence of a single quantum dot state on the characteristics of a microdisk laser. , 2007, Physical review letters.

[5]  P. Petroff,et al.  A quantum dot single-photon turnstile device. , 2000, Science.

[6]  Atsushi Uchida,et al.  Fast random bit generation with bandwidth-enhanced chaos in semiconductor lasers. , 2010, Optics express.

[7]  M. Bayer,et al.  Direct observation of correlations between individual photon emission events of a microcavity laser , 2009, Nature.

[8]  Frank Jahnke,et al.  Output characteristics of pulsed and continuous-wave-excited quantum-dot microcavity lasers. , 2008, Physical review letters.

[9]  S. Reitzenstein,et al.  Coherence properties of high-β elliptical semiconductor micropillar lasers , 2007 .

[10]  Gunnar Björk,et al.  Analysis of semiconductor microcavity lasers using rate equations , 1991 .

[11]  M. Kamp,et al.  Single quantum dot controlled lasing effects in high-Q micropillar cavities. , 2008, Optics express.

[12]  Paul D. Townsend,et al.  Quantum cryptography on multiuser optical fibre networks , 1997, Nature.

[13]  Ulrich Parlitz,et al.  Hyperchaotic dynamics and synchronization of external-cavity semiconductor lasers , 1998 .

[14]  John Whitfield,et al.  Complex systems: Order out of chaos , 2005, Nature.

[15]  Wolfgang Kinzel,et al.  Spiking optical patterns and synchronization. , 2007, Physical review. E, Statistical, nonlinear, and soft matter physics.

[16]  Ulrike Woggon,et al.  Photon statistics in the cooperative spontaneous emission. , 2009, Optics express.

[17]  Wolfgang Kinzel,et al.  Synchronization of random bit generators based on coupled chaotic lasers and application to cryptography. , 2010, Optics express.

[18]  Jia-Ming Liu,et al.  Synchronized chaotic optical communications at high bit rates , 2002 .

[19]  P. Jessen,et al.  Quantum signatures of chaos in a kicked top , 2009, Nature.

[20]  I. Kanter,et al.  An optical ultrafast random bit generator , 2010 .

[21]  A. Uchida,et al.  Fast physical random bit generation with chaotic semiconductor lasers , 2008 .

[22]  R. Lang,et al.  External optical feedback effects on semiconductor injection laser properties , 1980 .

[23]  Wolfgang Kinzel,et al.  Public channel cryptography: chaos synchronization and Hilbert's tenth problem. , 2008, Physical review letters.

[24]  Laurent Larger,et al.  Chaos-based communications at high bit rates using commercial fibre-optic links , 2005, Nature.

[25]  Laurent Larger,et al.  Nonlinear dynamics: Optoelectronic chaos , 2010, Nature.

[26]  Rajarshi Roy,et al.  Chaotic lasers: The world's fastest dice , 2008 .

[27]  S. Reitzenstein,et al.  Photon statistics of semiconductor microcavity lasers. , 2007, Physical review letters.

[28]  L. Grenouillet,et al.  Electrically driven high-Q quantum dot-micropillar cavities , 2008, 2008 Conference on Lasers and Electro-Optics and 2008 Conference on Quantum Electronics and Laser Science.

[29]  Christian Schneider,et al.  AlAs∕GaAs micropillar cavities with quality factors exceeding 150.000 , 2007 .

[30]  thomas e. Murphy,et al.  The World's Fastest Dice , 2008 .

[31]  Roy,et al.  Communication with chaotic lasers , 1998, Science.

[32]  I Kanter,et al.  Ultrahigh-speed random number generation based on a chaotic semiconductor laser. , 2009, Physical review letters.

[33]  D. Ritchie,et al.  An entangled-light-emitting diode , 2010, Nature.