Coworkers

Project status

Project description

Semiconductor lasers are key devices in many modern technological systems. In telecommunication, they are used for generating, transforming, and processing of signals at high speed. Due to the higher speed potential, in future telecommunication systems more and more functionalities beyond pure data transmission have to be realized in the optical domain. Monolithically integrated multi-section lasers are a class of compact, cheap, and reliable devices, which can be used for a variety of different functionalities. Within this class, at present the following types of devices are being developed: self pulsating lasers for optical clock recovery at 40 GHz, mode-locked lasers for generation of short pulses, directly modulated lasers for electro-optical signal conversion, and ring lasers for optical switching. All these devices operate typically not in a stationary state, but are designed to exhibit a specific nonlinear dynamical behavior, such as high frequency pulsations, short pulses, excitability, bistability, hysteresis and fast switching, locking on high-dimensional tori, synchronization of periodic, quasiperiodic or chaotic signals.

Besides telecommunication, semiconductor lasers with high brilliance are used for material processing, precision metrology, medicine as well as nonlinear optics and sensor technology. Such devices are realized as broad area or tapered lasers where also structures in the lateral direction of the cavity are of importance.

Mathematical modeling of the spatio-temporal dynamical behavior of semiconductor lasers leads to systems of dissipative hyperbolic PDEs (traveling-wave equations for the longitudinal optical fields) which are nonlinearly coupled with systems of ODEs for carrier densities. For tapered and broad area lasers the lateral space dimension has to be taken into account (field diffraction and carrier diffusion) which leads to coupled systems of nonlinear degenerated second order PDEs. As a specific feature these models typically include effects on different scales in space and time and have discontinuous coefficients (heterostructures).

Standard techniques and methods for a mathematical treatment of the nonlinear dynamical effects, like inertial manifolds or numerical bifurcation analysis by path following methods do not directly apply to systems of this type. In particular, methods for numerical bifurcation analysis for such dissipative hyperbolic systems of PDEs have to be developed, in order to investigate the dependence of dynamical effects on design and control parameters.

The general goal of the project is to support the technological development of such devices by numerical simulations and bifurcation analysis, based on an efficient modeling for the specific type of device, to validate and optimize the performance of existing devices according to system requirements and to create design rules for new dynamical effects, leading to new device concepts.

Expertise

Since about thirteen years we are engaged in modelling, analytical investigation and simulation of multisection DFB semiconductor lasers. Our results have been used in cooperation with the Fraunhofer Institut Nachrichtentechnik Heinrich-Hertz-Institut (HHI) and Ferdinand-Braun-Institut für Höchstfrequenztechnik (FBH) to design new laser devices. In cooperation with the Institut für Physik at Humboldt Universität zu Berlin (HU), the HHI and the FBH we have created an interdisciplinary seminar "Mathematische Modelle der Photonik", and have organized international workshops on laser dynamics and on synchronization and high-dimensional chaos in coupled systems.

Research program

The main challenge for the future is to follow the rapid technological development in the field of semiconductor laser devices by extending and adapting our mathematical methods and software tools to new classes of devices and corresponding models. In particular, we want to extend our activities in the new fields of quantum-dot lasers and high-power lasers. For quantum-dot lasers, we have to include effective models for the carrier exchange processes between bulk structure, wetting layer and quantum-dots into the software package LDSL-tool, in order to understand the specific dynamical properties of such devices. We expect some input in this direction from our project within the newly installed Sfb 787 "Nanophotonics". For broad area lasers, the understanding of basic nonlinear mechanisms for the onset of lateral instabilities and their influence on the beam quality is essential in order to optimize the brilliance of the laser. Moreover, we want to continue the research on multi-section lasers and micro-ring cavities, aiming in particular on new device concepts for optical communication systems.

From a mathematical point of view, this leads to the following research topics:

• Modeling and model reduction: For a mathematical description of complicated devices with structures from the scale of nm up to mm one has to use efficient models on different levels of complexity. For this, an understanding of fundamental physical models, including quantum effects, as well as their reduction to rate equation based phenomenological models is necessary.
• Regularity theory: Including the lateral dimension, the resulting nonlinear systems of 2D wave equations with discontinuous coefficients lead to unsolved mathematical problems concerning existence, regularity, and linearized stability in suitable function spaces. These questions are essential, in particular for an efficient numerical treatment and for later bifurcation analysis.
• Bifurcation theory and numerical bifurcation analysis: Numerical bifurcation analysis by path-following methods has proven to be a powerful tool for the investigation of spatio-temporal dynamics in semiconductor laser devices. Challenging questions are here the inclusion of lateral instabilities, symmetries, and corresponding spectral problems.
• Numerical methods: For the simulation of broad-area lasers and tapered lasers, the question of an efficient numerical method and parallelization will be of greater importance. We want to combine existing methods for an integration along characteristics with pseudo-spectral methods for the lateral dimension.

The final goal of the project is to create design rules for new dynamical effects, to support the experimental development by mathematical simulations, and to optimize existing devices, especially with respect to the dynamical performance (speed, robustness, system conformity). The numerical tools for simulation and numerical bifurcation analysis, which will be developed within the project, will be included into the software package LDSL-tool at WIAS.

Cooperation

Together with Matheon project D14 we study the generation of short pulses in a semiconductor laser and their transmission and shaping in nonlinear optical fibers . With project D23 we cooperate also within the Sfb 787 and investigate the optical properties of devices with nanostructures. Cooperation with C10 concerns PDEs with different scales in space and time, and asymptotic methods. With D21 we cooperate in the field of coupled systems and systems with delayed feedback.

In the field of quantum-dot lasers and nanophotonic structures, we cooperate within the framework of SFB 787 with D. Bimberg (TU Berlin), and E. Schöll (TU Berlin). Within the Marie Curie network PROPHET we cooperate with A. Ramdane (LPN CNRS, Marcoussis, FR) and F. Lelarge (Alcatel Thales III-V Lab, Marcoussis, FR).

Further cooperation partners are in the field of laser technology: Ferdinand Braun Institute (Berlin, DE), Tyndall National Institute (Cork, IE), Institut für Physik und Astronomie, (Potsdam University, DE); and in the field of modeling, analysis and software development: K. Staliunas (ICREA and UPC, Barcelona, ES) R. Ciegis (TU Vilnius, LT), E. Viktorov (ULB Brussels, BE), H.-J. Wünsche (HU Berlin, DE), G. Huyet, S. O'Brien (Tyndal Nat. Inst., Cork, IE), D. Rachinskii (Univ. Cork, IE).

List of publications made within the project

• M. Radziunas, M. Botey, R. Herrero, K. Staliunas, ''Intrinsic beam shaping mechanism in spatially modulated broad area semiconductor amplifiers'', to appear in Appl. Phys. Lett., 2013. WIAS-Preprint (1790).
• R. Arkhipov, A. Pimenov, M. Radziunas, D. Rachinskii, A. G. Vladimirov, D. Arsenijevic, H. Schmeckebier, D. Bimberg, ''Hybrid mode locking in semiconductor lasers: simulations, analysis and experiments'', to appear in IEEE J. of Selected Topics in Quantum Electronics 19(4), 2013. WIAS-Preprint (1734).
• G. Kitavtsev, L. Recke, B. Wagner, "Asymptotics for the spectrum of a thin film equation in a singular limit", SIAM J. Appl. Dyn. Syst. 11, pp. 1425-1457, 2012. WIAS-Preprint 1555, 2011.
• R. Čiegis, A. Mirinavičius, M. Radziunas, ''Comparison of split step solvers for multidimensional Schrödinger problems'', Computational Methods in Applied Mathematics 13(2), pp. 237-250, 2013.
• R. Herrero, M. Botey, M. Radziunas, K. Staliunas, ''Beam shaping in spatially modulated broad area semiconductor amplifiers'', Optics Letters 37(24), pp. 5253-5255, 2012.
• V. Tronciu, S. Schwertfeger, M. Radziunas, A. Klehr, U. Bandelow, H. Wenzel, ''Amplifications of picosecond laser pulses in tapered semiconductor amplifiers: Numerical simulations versus experiments'', Opt. Communications 285, pp. 2897-2904, 2012. WIAS-Preprint (1657), 2011.
• L. Recke, A. Samoilenko, V. Tkachenko, S. Yanchuk, "Frequency locking by external forcing in systems with rotational symmetry", SIAM J. Appl. Dyn. Syst. 11, pp. 771-800, 2012. arXiv:1108.5990v1, 2011.
• J. Ehrt, "Parameterizations of sub-attractors in hyperbolic balance laws", Proc. Roy. Soc. Edinburgh: Section A Mathematics, 142, pp. 1338-1342, 2012. WIAS-Preprint (1518), 2010.
• I. Kmit, L. Recke, ''Fredholmness and smooth dependence for linear hyperbolic periodic-Dirichlet problems'', J. Differ. Equations 252(2), pp. 1952-1986, 2012. Matheon preprint 701.
• M. Radziunas, K. Staliunas, ''Spatial rocking phenomenon in broad area semiconductor lasers'', Europhysics Letters, 95 art. no. 14002, 2011. WIAS-Preprint 1598.
• G. Kitavtsev, L. Recke, B. Wagner, "Center manifold reduction approach for the lubrication equation", Nonlinearity, 24, pp2347-2369, 2011.
• M. Radziunas, A.G. Vladimirov, E.A. Viktorov, G. Fiol, H. Schmeckebier, D. Bimberg, ''Pulse broadening in quantum-dot mode-locked semiconductor lasers: simulation, analysis and experiments'', IEEE J. of Quantum Electronics, 47(7), pp. 935-943, 2011. WIAS-Preprint 1584.
• L. Recke, A. Samoilenko, A. Teplinsky, V. Tkachenko, S. Yanchuk, ''Frequency locking of modulated waves'', Discrete and Continuous Dynamical Systems - Ser. A 31, pp. 847--875, 2011. Matheon preprint 707.
• M. Radziunas, K.-H. Hasler, B. Sumpf, Tran Quoc Tien, H. Wenzel, ''Mode transitions in DBR semiconductor lasers: Experiments, simulations and analysis'', J. Phys. B: At. Mol. Opt. Phys. 44 art. no. 105401, 2011. WIAS-Preprint 1513.
• M. Lichtner, M. Wolfrum, S. Yanchuk, ''The Spectrum of Delay Differential Equations with Large Delay'', SIAM J. Math. Anal., 43(2), pp. 788-802, 2011. WIAS-Preprint 1436.
• M. Radziunas, A.G. Vladimirov, E.A. Viktorov, G. Fiol, H. Schmeckebier, D. Bimberg, ''Strong pulse asymmetry in quantum-dot mode-locked semiconductor lasers'', Appl. Phys. Lett., 98, art. no. 031104, 2011. WIAS-Preprint 1579.
• P. Perlikowski, S. Yanchuk, M. Wolfrum, A. Stefanski, P. Mosiolek, T. Kapitaniak, "Routes to complex dynamics in a ring of unidirectionally coupled systems", Chaos 20, art. no. 013111, 2010.
• R. Čiegis, M. Radziunas, ''Effective Numerical Integration of Traveling Wave Model for Edge-Emitting Broad-Area Semiconductor Lasers and Amplifiers'', Math. Model. Anal. 15(4), pp. 409-430, 2010.
• V.Z. Tronciu, M. Lichtner, M. Radziunas, U. Bandelow, H. Wenzel, ''Improving the stability of distributed-feedback tapered master-oscillator power-amplifiers'', Optical and Quantum Electronics, 41(7), pp. 531-537, 2009. WIAS-Preprint 1444.
• R. Čiegis, I. Laukaitytė, M. Radziunas, ''Numerical algorithms for Schrödinger equation with artificial boundary conditions'', Num. Funct. Anal. and Optimization, 30(9-10), pp. 903-923, 2009. WIAS-Preprint 1446.
• A. Jechow, M. Lichtner, R. Menzel, M. Radziunas, D. Skoczowsky, A. Vladimirov, ''Stripe-array diode-laser in an off-axis external cavity: Theory and experiment'', Optics Express, 17(22), pp. 19599-19604, 2009. WIAS-Preprint 1442.
• M. Spreemann, M. Lichtner, M. Radziunas, U. Bandelow, H. Wenzel, ''Measurement and Simulation of Distributed-Feedback Tapered Master-Oscillators Power-Amplifiers'', IEEE J. of Quantum Electronics, 45(6), pp. 609-616, 2009.
• M. Radziunas, V.Z. Tronciu, U. Bandelow, M. Lichtner, M. Spreemann, H. Wenzel, ''Mode transitions in distributed-feedback tapered master-oscillator power-amplifier'', Optical and Quantum Electronics, 40(14-15), pp. 1103-1109, 2008. WIAS-Preprint, 1366.
• M. Lichtner, "Variation of constants formula for hyperbolic systems", J. of Appl. Anal., 15(1), pp. 79-100, 2009. WIAS-Preprint 1212.
• R. Ciegis, M. Radziunas, M. Lichtner, ''Numerical algorithms for simulation of multisection lasers by using traveling wave model'', Math. Model. Anal. 13(3), pp. 327-348, 2008.
• D. Turaev, M. Radziunas, A. Vladimirov, ''Chaotic soliton walk in periodically modulated media'', Phys. Rev. E, 77(1), art. no. 065201(R), 2008. WIAS-Preprint 1262.
• S. Yanchuk, M. Wolfrum, ''Destabilization patterns in chains of coupled oscillators'', Phys. Rev. E, 77 art. no. 026212, 2008. WIAS-Preprint 1213.
• M. Lichtner, ''Spectral mapping theorem for linear hyperbolic systems'', Proc. Amer. Math. Soc., 136 2091-2101, 2008. WIAS-Preprint 1150.
• E.A. Viktorov, P. Mandel, M. Kuntz, G. Fiol, D. Bimberg, A.G. Vladimirov, M. Wolfrum, ''Stability of the modelocked regime in quantum dot lasers'', Appl. Phys. Lett., 91, art. no.231116, 2007.
• I. Kmit, L. Recke, ''Fredholm alternative for periodic-Dirichlet problems for linear hyperbolic systems'', J. Math. Anal. Appl., 335 355-370, 2007. Preprint of DFG Research Center Matheon 342.
• O.V. Ushakov, N. Korneyev, M. Radziunas, H.-J. Wünsche, F. Henneberger, ''Excitability of chaotic transients in a semiconductor laser'', Europhysics Letters, 79 30004 (5pp), 2007.
• M. Radziunas, A. Glitzky, U. Bandelow, M. Wolfrum, U. Troppenz, J. Kreissl, W. Rehbein, ''Improving the modulation bandwidth in semiconductor lasers by passive feedback'', IEEE J. of Selected Topics of Quantum Electronics, 13(1), pp. 136-142, 2007. WIAS-Preprint 1149.
• M. Lichtner, M. Radziunas, L. Recke, ''Well posedness, smooth dependence and center manifold reduction for a semilinear hyperbolic system from laser dynamics'', Mathematical Methods in Applied Sciences, 30(8), pp. 931-960, 2007.
• T. Perez, M. Radziunas, H.-J. Wünsche, C.R. Mirasso, F. Henneberger, ''Synchronization properties of two coupled multisection semiconductor lasers emitting chaotic light'', Phot. Techn. Lett., 18(20), pp. 2135-2137, 2006.
• S. Yanchuk, M. Wolfrum, P. Hövel, E. Schöll, ``Control of unstable steady states by strongly delayed feedback'', Phys. Rev. E. 74, art. no. 026201, 2006. WIAS-Preprint 1122.
• U. Bandelow, M. Radziunas, A. Vladimirov, B. Hüttl, R. Kaiser, ''Harmonic Mode-Locking in Monolithic Semiconductor Lasers: Theory, Simulations and Experiment'', Optical and Quantum Electronics 38, pp. 495-512, 2006. WIAS-Preprint 1039.
• B. Hüttl, R. Kaiser, Ch. Kindel, S.Fiddora, W. Rehbein, H. Stolpe, G. Sahin, U. Bandelow, M. Radziunas, A. Vladimirov, H. Heidrich, ''Experimental investigations on the suppression of Q-switching in monolithic 40 GHz mode-locked semiconductor lasers'', Appl. Phys. Lett. 88, art. no. 221104, 2006. WIAS-Preprint 1112.
• M. Wolfrum, S. Yanchuk, ``Eckhaus instability in systems with large delay'', Phys. Rev. Lett. 96, art. no. 220201, 2006. WIAS-Preprint 1101.
• M. Nizette, D. Rachinskii, A. Vladimirov, M. Wolfrum, ``Pulse interaction via gain and loss dynamics in passive mode-locking'', Physica D, 218(1), pp. 95-104, 2006. WIAS-Preprint 1060.
• V.Z. Tronciu, H.-J. Wünsche, M. Wolfrum, M. Radziunas, ''Semiconductor laser under resonant feedback from a Fabry-Perot resonator: Stability of continuous wave operation'', Phys. Rev. E 73, art. no. 046205, 2006. WIAS-Preprint 1051.
• M. Radziunas, ''Numerical bifurcation analysis of traveling wave model of multisection semiconductor lasers'', Physica D, 213(1), pp. 98-112, 2006. WIAS-Preprint 985.
• M. Radziunas, F. Ivanauskas, "The convergence and stability of splitting finite difference schemes for nonlinear evolutionary type equations", Lith. Math. Journal, 45(3), pp. 413-434, 2005. WIAS-Preprint 464.
• M. Radziunas, H.-J. Wünsche, ''Multisection Lasers: Longitudinal Modes and their Dynamics'', in Optoelectronic Devices - Advanced Simulation and Analysis, pp. 121-150, ed. J. Piprek, Springer Verlag, New York, 2005. ISBN: 0-387-22659-1 WIAS-Preprint 939.
• J. Sieber, L. Recke, K.R. Schneider, ''Dynamics of multisection semiconductor lasers'', J. Math. Sci. (N. Y.), 124(5), pp. 5298-5309, 2004.
• S. Yanchuk, K. R. Schneider, L. Recke, ''Dynamics of two mutually coupled semiconductor lasers: Instantaneous coupling limit'', Phys. Rev. E, 69, 056221, 2004. WIAS-Preprint 879.
• S. Bauer, O. Brox, J. Kreissl, B. Sartorius, M. Radziunas, J. Sieber, H.-J. Wünsche, F. Henneberger ''Nonlinear Dynamics of Semiconductor Lasers with Active Optical Feedback'', Phys. Rev. E 69, 016206, 2004. WIAS-Preprint 866.
• J. Sieber, M. Radziunas, K. Schneider, ''Dynamics of multisection semiconductor lasers'', Math. Model. Anal. 9(1), pp. 51-66, 2004. pdf file.
• K. Schneider, S. Yanchuk, ''Complete synchronization of symmetrically coupled autonomous systems'', Appl. Anal., 82, pp.1127-1143, 2003. WIAS-Preprint 833.
• H.-J. Wünsche, M. Radziunas, S. Bauer, O. Brox, B. Sartorius, "Simulation of Phase-Controlled Mode-Beating Lasers", IEEE J Selected Topics of Quantum Electron. 9(3), pp. 857-864, 2003. WIAS-Preprint 809.
• O. Brox, S. Bauer, M. Radziunas , M. Wolfrum, J. Sieber, J. Kreissl, B. Sartorius, H.-J. Wünsche, ''High-Frequency Pulsations in DFB-Lasers with Amplified Feedback'', IEEE J Quantum Elect., 39(11), pp. 1381-1387, 2003. WIAS-Preprint 849.
• B. Krauskopf, K. Schneider, J. Sieber, S. Wieczorek, M. Wolfrum: Excitability and self-pulsations near homoclinic bifurcations in semiconductor laser systems, Optics Comm., Vol 215, pp. 367-379, 2003. WIAS-Preprint 750.
• H.-J. Wünsche, O. Brox, M. Radziunas, F. Henneberger, "Excitability of a semiconductor laser by a two-mode homoclinic bifurcation", Phys. Rev. Lett. 88(2), art. no. 023901, 2002. pdf file.
• M. Wolfrum, D. Turaev, Instabilities of Lasers with moderately delayed optical feedback, Optics Comm., 212, pp. 127-138, 2002. WIAS-Preprint 714.
• F. Jochmann, L. Recke, Well-posedness of an initial boundary value problem from laser dynamics , Math. Models Methods Appl. Sci., 12(4), pp. 593-606, 2002. WIAS-Preprint 515.

• I. Laukaityte, R. Ciegis, M. Lichtner, M. Radziunas, ''Parallel numerical algorithm for the traveling wave model'', in Parallel Scientific Computing and Optimization: Advances and Applications, eds. R. Ciegis, D. Henty, B. Kagstrom and J. Zilinskas, Vol. 27, Springer, pp. 237-251, 2009. ISBN 978-0-387-09706-0.
• L. Recke, M. Wolfrum, S. Yanchuk, ``Dynamics of coupled semiconductor lasers'', in: Analysis and Control of Complex Nonlinear Processes in Physics, Chemistry and Biology, Chapter 6, L. Schimansky-Geier, B. Fiedler, J. Kurths, E. Schöll, eds., World Scientific, pp. 185-212, 2007.
• M. Radziunas, H.-J. Wünsche, ''Multisection Lasers: Longitudinal Modes and their Dynamics'', in Optoelectronic Devices - Advanced Simulation and Analysis, Chapter 5, J. Piprek ed., Springer Verlag, New York. pp. 121-150, 2005. WIAS-Preprint 939.

• R. Herrero, M. Botey, M. Radziunas, K. Staliunas, ''Beam shaping in spatially modulated broad area semiconductor amplifiers'', in Proc. of the CLEO Europe/IQEC Conference, IG-2.4 WED, Munich, May 12-16, 2013. pdf file.
• M. Radziunas, R. Herrero, M. Botey, K. Staliunas, ''Theoretical study of beam quality improvement in spatially modulated broad area edge-emitting devices'', in Proc. of the CLEO Europe/IQEC Conference, CB-P.38 MON, Munich, May 12-16, 2013. pdf file.
• M. Radziunas, ''Traveling wave modelling and mode analysis of semiconductor ring lasers'', in Proc. of the CLEO Europe/IQEC Conference, CB-P.37 MON, Munich, May 12-16, 2013. pdf file.
• M. Radziunas, K. Staliunas, ''Spatial"rocking" for improving the spatial quality of the beam of broad area semiconductor lasers'', in SPIE Proceedings Series, (8432), art. no. 84320Q, 2012. WIAS-Preprint, (1703).
• M. Radziunas, K. Staliunas, "Spatial "rocking" in broad emission area semiconductor lasers", in Proc. of the CLEO Europe/EQEC Conference, CB5.2 WED, Munich, May 22-26, 2011. pdf file.
• M. Radziunas, A.G. Vladimirov, E.A. Viktorov, G. Fiol, H. Schmeckebier, D. Bimberg, "Strong asymmetry of mode-locking pulses in quantum-dot semiconductor lasers", in Proc. of the CLEO Europe/EQEC Conference, CB3.5 TUE, Munich, May 22-26, 2011. pdf file.
• M. Radziunas, A.G. Vladimirov, E. Viktorov, ''Traveling wave modeling, simulation and analysis of quantum-dot mode-locked semiconductor lasers'', in SPIE Proceedings Series, (7720), art. no. 77200X, 2010. WIAS-Preprint 1506.
• A. Jechow, D. Skoczowsky, M. Lichtner, M. Radziunas, R. Menzel, "High-brightness emission from stripe-array broad area diode lasers operated in off-axis external cavities", in SPIE Proceedings Series, (7583), art. no. 758312, 2010.
• V.Z. Tronciu, M. Lichtner, M. Radziunas, U. Bandelow, H. Wenzel, "Dynamics and stability improvement of DFB tapered master-oscillator power-amplifiers", Proc. of the 6th International Conference on Microelectronics and Computer Science , Chisinau, Republic of Moldova, October 1-3, pp. 15-18, 2009. pdf file.
• V.Z. Tronciu, M. Lichtner, M. Radziunas, U. Bandelow, H. Wenzel, "Improving the stability of distributed-feedback tapered master-oscillator power-amplifiers", Proc. of the 9th Int. Conf. on Numerical Simulation of Optoelectronic Devices NUSOD 09 , J. Piprek, Yong-Tak Lee, eds., pp. 55-56, 2009. pdf file.
• M. Radziunas, A.G. Vladimirov, E. Viktorov, "Traveling wave modeling of mode-locked quantum dot semiconductor lasers", in Proc. of the CLEO Europe/EQEC Conference, CB4.4 TUE, Munich, June 14-19, 2009. pdf file.
• M. Radziunas, "Simulation of switching between stable unidirectional states in semiconductor ring lasers", in Proc. of the CLEO Europe/EQEC Conference, CB.P.12 TUE, Munich, June 14-19, 2009. pdf file.
• V.Z. Tronciu, M. Lichtner, M. Radziunas, U. Bandelow, H. Wenzel, "Calculation of improved features of distributed-feedback tapered master-oscillator power-amplifiers", in Proc. of the CLEO Europe/EQEC Conference, CB.P.30 TUE, Munich, June 14-19, 2009. pdf file.
• E.V. Viktorov, P. Mandel, A.G. Vladimirov, M. Wolfrum, G. Fiol, M. Kuntz, D. Bimberg, "Calculation of improved features of distributed-feedback tapered master-oscillator power-amplifiers", in Proc. of the CLEO Europe/EQEC Conference, CB4.2 TUE, Munich, June 14-19, 2009. pdf file.
• M. Lichtner, M. Radziunas, U. Bandelow, M. Spreemann, H. Wenzel, ''Dynamic simulation of high brightness semiconductor lasers'', 8th Int. Conf. on Numerical Simulation of Optoelectronic Devices NUSOD 08 , J. Piprek, E. Larkins, eds., Nottingham, UK, September 1-5, 2008. pdf file.
• M. Radziunas, ''Traveling wave modeling of semiconductor ring lasers'', in SPIE Proceedings Series, (6997), art. no. 69971B, 2008. WIAS-Preprint, (1315).
• J. Kreissl, U. Troppenz, W. Rehbein, T. Gaertner, P. Harde, M. Radziunas, ''40 Gb/s direct modulated passive feedback laser with complex-coupled DFB section'', in Proc. of the 33rd European Conf. on Optical Communications ECOC 2007, Vol. 3, pp 213-214, 8.1.4, Berlin, Germany, September 16-20, 2007.
• T. Perez, C.R. Mirasso, H-J. Wünsche, F. Henneberger, M. Radziunas, I. Fischer, ''Synchronization of Chaotic Unidirectionally Coupled Multisection Lasers'', in Proc. of the CLEO Europe/IQEC Conference, JSI3-2-THU, Munich, June 17-22, 2007. pdf file.
• O. Ushakov, H-J. Wünsche, F. Henneberger, M. Radziunas, ''Excitability of Chaotic Transients in a Semiconductor Laser'', in Proc. of the CLEO Europe/IQEC Conference, IG6-2-THU, Munich, June 17-22, 2007. pdf file.
• M. Radziunas, U. Troppenz, J. Kreissl, ''Tailoring single-mode DFB laser with integrated passive feedback section for direct modulation applications'', in Proc. of the CLEO Europe/IQEC Conference, CB-35-WED, Munich, June 17-22, 2007. pdf file.
• E.A. Viktorov, P. Mandel, M. Kuntz, G. Fiol, D. Bimberg, A.G. Vladimirov, M. Wolfrum, ''Stability of the modelocking regime in quantum dot laser'', in Proc. of the CLEO Europe/IQEC Conference, IG6-3-THU, Munich, June 17-22, 2007. pdf file.
• U. Troppenz, J. Kreissl, W. Rehbein, C. Bornholdt, T. Gaertner, M. Radziunas, A. Glitzky, U. Bandelow, M. Wolfrum, ''40 Gb/s directly modulated InGaAsP passive feedback DFB laser'', in ECOC Proceedings Series , Postdeadline session, paper Th 4.5.5, 2006.
• T. Perez, M. Radziunas, H.-J. Wünsche, C.R. Mirasso, F. Henneberger, ''Chaos synchronization of unidirectionally coupled multisection lasers'', in ECOC Proceedings Series , CLEO Focus Meeting on Chaotic Optical Systems and Applications, paper Tu 3.1.5, 2006.
• M. Radziunas, H.-J. Wünsche, B. Krauskopf, M. Wolfrum, '' External cavity modes in Lang-Kobayashi and traveling wave models'', in SPIE Proceedings Series, (6184), art. no. 61840X, 2006. WIAS-Preprint 1111.
• M. Radziunas, U. Bandelow, M. Wolfrum, U. Troppenz, J. Kreissl, A. Glitzky, R. Hünlich, ''Design of multisection laser for 40 Gb/s direct modulation'', in Proc. of the 31st European Conf. on Optical Communications ECOC 2005, Vol. 3, pp 677-678, We4.P.088, Glasgow, UK, September 25-29 2005. pdf file.
• M. Radziunas, ''Tailoring the dynamics of multisection lasers for 40 Gb/s direct modulation'', in Proc. of the 5th Int. Conf. on Numerical Simulation of Optoelectronic Devices NUSOD 05 (ed. H.-J. Wünsche, J. Piprek, U. Bandelow, H. Wenzel), pp 29-30, Berlin, Germany, September 19-22 2005. IEEE Catalog Number: 05EX1074. pdf file.
• U. Troppenz, M. Hamacher, M. Radziunas, H. Heidrich, ''Optical switching of clokwise/anti-clokwise lasing in bus coupled microrings'', in Proc. of the 17th Int. Conf. on Indium Phosphide and Related Materials IPRM 05 (ed. I. Thayne, J. Marsh, C. Bryce), Glasgow, Scotland, UK, May 8-12 2005. IEEE Catalog Number: 05CH37633C.
• S. Yanchuk, K.R. Schneider, L. Recke, ''Dynamics of two F2F coupled lasers: instantaneous coupling limit'', in SPIE Proceedings Series, (5452), pp. 51-62, 2004.
• N. Korneyev, M. Radziunas, H.-J. Wünsche, F. Henneberger, ''Mutually injecting semiconductor lasers: simulations for short and zero delay'', in SPIE Proceedings Series, (5452), pp. 63-70, 2004. pdf file.
• N. Korneyev, M. Radziunas, H.-J. Wünsche, F. Henneberger, ''Bifurcations of a DFB Laser with Short Optical Feedback: Numerical Experiment'', in SPIE Proceedings Series, (4986), pp. 480-489, 2003. pdf file.
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