@article{ElsnerPuhlmannPieplowetal.2015, author = {Elsner, Robert and Puhlmann, Dirk and Pieplow, Gregor and Heuer, Axel and Menzel, Ralf}, title = {Transverse distinguishability of entangled photons with arbitrarily shaped spatial near- and far-field distributions}, series = {Journal of the Optical Society of America : B, Optical physics}, volume = {32}, journal = {Journal of the Optical Society of America : B, Optical physics}, number = {9}, publisher = {Optical Society of America}, address = {Washington}, issn = {0740-3224}, doi = {10.1364/JOSAB.32.001910}, pages = {1910 -- 1919}, year = {2015}, abstract = {Entangled photons generated by spontaneous parametric downconversion are ubiquitous in quantum optics. In general, they exhibit a complex spatial photon count distribution. This spatial structure is responsible for seemingly surprising results concerning, e.g., complementarity such as the apparent simultaneous observation of interference fringes V and which-way information D at a double slit, as recently reported by Menzel et al. [Proc. Natl. Acad. Sci. USA 109, 9314 (2012)]. We implement a complete quantitative model of the SPDC interaction that fully incorporates the effects of crystal anisotropies, phase matching, and the pump beam structure and allows for arbitrary manipulations of the SPDC light in the near and far fields. This enables us to establish an upper bound D-2 + V-2 <= 1.47 for the experimental parameters reported by Menzel et al. We report new experimental results that agree excellently with these theoretical predictions. The new model enables a detailed quantitative analysis of this surprising result and the fair sampling interpretation of biphotons passing a double slit. (C) 2015 Optical Society of America}, language = {en} } @article{HeuerMenzelMilonni2015, author = {Heuer, Axel and Menzel, Ralf and Milonni, P. W.}, title = {Complementarity in biphoton generation with stimulated or induced coherence}, series = {Physical review : A, Atomic, molecular, and optical physics}, volume = {92}, journal = {Physical review : A, Atomic, molecular, and optical physics}, number = {3}, publisher = {American Physical Society}, address = {College Park}, issn = {1050-2947}, doi = {10.1103/PhysRevA.92.033834}, pages = {8}, year = {2015}, abstract = {Coherence can be induced or stimulated in parametric down-conversion using two or three crystals when, for example, the idler modes of the crystals are aligned. Previous experiments with induced coherence [Phys. Rev. Lett. 114, 053601 (2015)] focused on which-path information and the role of vacuum fields in realizing complementarity via reduced visibility in single-photon interference. Here we describe experiments comparing induced and stimulated coherence. Different single-photon interference experiments were performed by blocking one of the pump beams in a three-crystal setup. Each counted photon is emitted from one of two crystals and which-way information may or not be available, depending on the setup. Distinctly different results are obtained in the induced and stimulated cases, especially when a variable transmission filter is inserted between the crystals. A simplified theoretical model accounts for all the experimental results and is also used to address the question of whether the phases of the signal and idler fields in parametric down-conversion are correlated.}, language = {en} } @article{ZinkWernerJechowetal.2014, author = {Zink, Christof and Werner, Nils and Jechow, Andreas and Heuer, Axel and Menzel, Ralf}, title = {Multi-wavelength operation of a single broad area diode laser by spectral beam combining}, series = {IEEE photonics technology letters}, volume = {26}, journal = {IEEE photonics technology letters}, number = {3}, publisher = {Inst. of Electr. and Electronics Engineers}, address = {Piscataway}, issn = {1041-1135}, doi = {10.1109/LPT.2013.2291963}, pages = {253 -- 256}, year = {2014}, abstract = {Stabilized multi-wavelength emission from a single emitter broad area diode laser (BAL) is realized by utilizing an external cavity with a spectral beam combining architecture. Self-organized emitters that are equidistantly spaced across the slow axis are enforced by the spatially distributed wavelength selectivity of the external cavity. This resulted in an array like near-field emission although the BAL is physically a single emitter without any epitaxial sub-structuring and only one electrical contact. Each of the self-organized emitters is operated at a different wavelength and the emission is multiplexed into one spatial mode with near-diffraction limited beam quality. With this setup, multi-line emission of 31 individual spectral lines centered around and a total spectral width of 3.6 nm is realized with a 1000 mu m wide BAL just above threshold. To the best of our knowledge, this is the first demonstration of such a self-organization of emitters by optical feedback utilizing a spectral beam combining architecture.}, language = {en} } @article{ZinkNiebuhrJechowetal.2014, author = {Zink, Christof and Niebuhr, Mario and Jechow, Andreas and Heuer, Axel and Menzel, Ralf}, title = {Broad area diode laser with on-chip transverse Bragg grating stabilized in an off-axis external cavity}, series = {Optics express : the international electronic journal of optics}, volume = {22}, journal = {Optics express : the international electronic journal of optics}, number = {12}, publisher = {Optical Society of America}, address = {Washington}, issn = {1094-4087}, doi = {10.1364/OE.22.014108}, pages = {14108 -- 14113}, year = {2014}, abstract = {The emission characteristics of a novel, specially designed broad area diode laser (BAL) with on-chip transversal Bragg resonance (TBR) grating in lateral direction were investigated in an off-axis external cavity setup. The internal TBR grating defines a low loss transversal mode at a specific angle of incidence and a certain wavelength. By providing feedback at this specific angle with an external mirror, it is possible to select this low loss transverse mode and stabilize the BAL. Near diffraction limited emission with an almost single lobed far field pattern could be realized, in contrast to the double lobed far field pattern of similar setups using standard BALs or phase-locked diode laser arrays. Furthermore, we could achieve a narrow bandwidth emission with a simplified setup without external frequency selective elements. (C) 2014 Optical Society of America}, language = {en} } @article{HeuerRaabeMenzel2014, author = {Heuer, Axel and Raabe, S. and Menzel, Ralf}, title = {Phase memory across two single-photon interferometers including wavelength conversion}, series = {Physical review : A, Atomic, molecular, and optical physics}, volume = {90}, journal = {Physical review : A, Atomic, molecular, and optical physics}, number = {4}, publisher = {American Physical Society}, address = {College Park}, issn = {1050-2947}, doi = {10.1103/PhysRevA.90.045803}, pages = {4}, year = {2014}, abstract = {Spontaneous parametric down-conversion (SPDC) in a nonlinear crystal generates two single photons (signal and idler) with random phases. Thus, no first-order interference between them occurs. However, coherence can be induced in a cascaded setup of two crystals if, e.g., the idler modes of both crystals are aligned to be indistinguishable. Due to the effect of phase memory it is found that the first-order interference of the signal beams can be controlled by the phase delay between the pump beams. Even for pump photon delays much larger than the coherence length of the SPDC photons, the visibility is above 90\%. The high visibilities reported here prove an almost perfect phase memory effect across the two interferometers for the pump and the signal photon modes.}, language = {en} } @article{HeuerSagahtiJechowetal.2012, author = {Heuer, Axel and Sagahti, A. and Jechow, Andreas and Skoczowsky, D. and Menzel, Ralf}, title = {Multi-wavelength, high spatial brightness operation of a phase-locked stripe-array diode laser}, series = {Laser physics}, volume = {22}, journal = {Laser physics}, number = {1}, publisher = {Pleiades Publ.}, address = {New York}, issn = {1054-660X}, doi = {10.1134/S1054660X12010057}, pages = {160 -- 164}, year = {2012}, abstract = {Stable continuous wave multi-wavelength operation of a stripe-array diode laser with an externalcavity spectral beam combining geometry is presented. In this setup each emitter of the stripe-array is forced to operate at a different wavelength, which leads to a decoupling between the usually phase-locked emitters. With a reflective diffraction grating with a period of 300 lines per mm, 33 equidistant laser lines around a center wavelength of 978 nm were realized, spanning a spectral range of 26 nm. With this novel approach near-diffraction limited emission with a beam quality of M (2) < 1.2 and an output power of 450 mW was achieved. This laser light source can be used for applications requiring low temporal but high spatial coherence.}, language = {en} } @article{MenzelPuhlmannHeueretal.2012, author = {Menzel, Ralf and Puhlmann, Dirk and Heuer, Axel and Schleich, Wolfgang P.}, title = {Wave-particle dualism and complementarity unraveled by a different mode}, series = {Proceedings of the National Academy of Sciences of the United States of America}, volume = {109}, journal = {Proceedings of the National Academy of Sciences of the United States of America}, number = {24}, publisher = {National Acad. of Sciences}, address = {Washington}, issn = {0027-8424}, doi = {10.1073/pnas.1201271109}, pages = {9314 -- 9319}, year = {2012}, abstract = {The precise knowledge of one of two complementary experimental outcomes prevents us from obtaining complete information about the other one. This formulation of Niels Bohr's principle of complementarity when applied to the paradigm of wave-particle dualism-that is, to Young's double-slit experiment-implies that the information about the slit through which a quantum particle has passed erases interference. In the present paper we report a double-slit experiment using two photons created by spontaneous parametric down-conversion where we observe interference in the signal photon despite the fact that we have located it in one of the slits due to its entanglement with the idler photon. This surprising aspect of complementarity comes to light by our special choice of the TEM01 pump mode. According to quantum field theory the signal photon is then in a coherent superposition of two distinct wave vectors giving rise to interference fringes analogous to two mechanical slits.}, language = {en} } @article{GarzSandmannRadingetal.2012, author = {Garz, Andreas and Sandmann, Michael and Rading, Michael and Ramm, Sascha and Menzel, Ralf and Steup, Martin}, title = {Cell-to-cell diversity in a synchronized chlamydomonas culture as revealed by single-cell analyses}, series = {Biophysical journal}, volume = {103}, journal = {Biophysical journal}, number = {5}, publisher = {Cell Press}, address = {Cambridge}, issn = {0006-3495}, doi = {10.1016/j.bpj.2012.07.026}, pages = {1078 -- 1086}, year = {2012}, abstract = {In a synchronized photoautotrophic culture of Chlamydomonas reinhardtii, cell size, cell number, and the averaged starch content were determined throughout the light-dark cycle. For single-cell analyses, the relative cellular starch was quantified by measuring the second harmonic generation (SHG). In destained cells, amylopectin essentially represents the only biophotonic structure. As revealed by various validation procedures, SHG signal intensities are a reliable relative measure of the cellular starch content. During photosynthesis-driven starch biosynthesis, synchronized Chlamydomonas cells possess an unexpected cell-to-cell diversity both in size and starch content, but the starch-related heterogeneity largely exceeds that of size. The cellular volume, starch content, and amount of starch/cell volume obey lognormal distributions. Starch degradation was initiated by inhibiting the photosynthetic electron transport in illuminated cells or by darkening. Under both conditions, the averaged rate of starch degradation is almost constant, but it is higher in illuminated than in darkened cells. At the single-cell level, rates of starch degradation largely differ but are unrelated to the initial cellular starch content. A rate equation describing the cellular starch degradation}, language = {en} } @article{MenzelHeuerPuhlmannetal.2013, author = {Menzel, Ralf and Heuer, Axel and Puhlmann, Dirk and Dechoum, K. and Hillery, M. and Spaehn, M. J. A. and Schleich, W. P.}, title = {A two-photon double-slit experiment}, series = {Journal of modern optics}, volume = {60}, journal = {Journal of modern optics}, number = {1}, publisher = {Routledge, Taylor \& Francis Group}, address = {Abingdon}, issn = {0950-0340}, doi = {10.1080/09500340.2012.746400}, pages = {86 -- 94}, year = {2013}, abstract = {We employ a photon pair created by spontaneous parametric down conversion (SPDC) where the pump laser is in the TEM01 mode to perform a Young's double-slit experiment. The signal photon illuminates the two slits and displays interference fringes in the far-field while the idler photon measured in the near-field in coincidence with the signal photon provides us with which-slit' information. We explain the results of these experiments with the help of an analytical expression for the second-order correlation function derived from an elementary model of SPDC. Our experiment emphasizes the crucial role of the mode function in the quantum theory of radiation.}, language = {en} } @article{JechowSeefeldtKurzkeetal.2013, author = {Jechow, Andreas and Seefeldt, Michael and Kurzke, Henning and Heuer, Axel and Menzel, Ralf}, title = {Enhanced two-photon excited fluorescence from imaging agents using true thermal light}, series = {Nature photonics}, volume = {7}, journal = {Nature photonics}, number = {12}, publisher = {Nature Publ. Group}, address = {London}, issn = {1749-4885}, doi = {10.1038/NPHOTON.2013.271}, pages = {973 -- 976}, year = {2013}, abstract = {Two-photon excited fluorescence (TPEF) is a standard technique in modern microscopy(1), but is still affected by photodamage to the probe. It has been proposed that TPEF can be enhanced using entangled photons(2,3), but this has proven challenging. Recently, it was shown that some features of entangled photons can be mimicked with thermal light, which finds application in ghost imaging(4), subwavelength lithography(5) and metrology(6). Here, we use true thermal light from a superluminescent diode to demonstrate TPEF that is enhanced compared to coherent light, using two common fluorophores and luminescent quantum dots, which suit applications in imaging and microscopy. We find that the TPEF rate is directly proportional to the measured(7) degree of second-order coherence, as predicted by theory. Our results show that photon bunching in thermal light can be exploited in two-photon microscopy, with the photon statistic providing a new degree of freedom.}, language = {en} } @article{JechowLichtnerMenzeletal.2009, author = {Jechow, Andreas and Lichtner, Mark and Menzel, Ralf and Radziunas, Mindaugas and Skoczowsky, Danilo and Vladimirov, Andrei G.}, title = {Stripe-array diode-laser in an off-axis external cavity : theory and experiment}, issn = {1094-4087}, doi = {10.1364/OE.17.019599}, year = {2009}, abstract = {Stripe-array diode lasers naturally operate in an anti-phase supermode. This produces a sharp double lobe far field at angles +/-alpha depending on the period of the array. In this paper a 40 emitter gain guided stripe-array laterally coupled by off-axis filtered feedback is investigated experimentally and numerically. We predict theoretically and confirm experimentally that at doubled feedback angle 2 alpha a stable higher order supermode exists with twice the number of emitters per array period. The theoretical model is based on time domain traveling wave equations for optical fields coupled to the carrier density equation taking into account diffusion of carriers. Feedback from the external reflector is modeled using Fresnel integration.}, language = {en} } @article{SkoczowskyJechowStuermeretal.2010, author = {Skoczowsky, Danilo and Jechow, Andreas and St{\"u}rmer, Herbert and Poßner, Torsten and Sacher, Joachim and Menzel, Ralf}, title = {Quasi-monolithic ring resonator for efficient frequency doubling of an external cavity diode laser}, issn = {0946-2171}, doi = {10.1007/s00340-009-3802-7}, year = {2010}, abstract = {A quasi-monolithic second-harmonic-generation ring resonator assembled with miniaturized components is presented. The ring contains a 10-mm-long bulk periodically poled lithium niobate crystal for second-harmonic generation, four plane mirrors and two gradient-index lenses. All parts are mounted on a glass substrate with an overall size of 19.5 mmx8.5 mmx4 mm. As pump source a broad-area laser diode operated in an external resonator with Littrow arrangement is utilized. This external cavity diode laser provides near diffraction limited, narrow-bandwidth emission with an optical output power of 450 mW at a wavelength of 976 nm. Locking of the diode laser emission to the resonance frequency of the ring cavity was achieved by an optical self-injection locking technique. With this setup more than 126 mW of diffraction-limited blue light at 488 nm could be generated. The opto-optical conversion efficiency was 28\% and a wall plug efficiency better than 5.5\% could be achieved.}, language = {en} } @article{KappeMenzelOstermeyer2006, author = {Kappe, Philip and Menzel, Ralf and Ostermeyer, Martin}, title = {Analysis of the temporal and spectral output properties of a mode-locked and Q-switched laser oscillator with a nonlinear mirror based on stimulated Brillouin scattering}, issn = {1050-2947}, doi = {10.1103/Physreva.74.013809}, year = {2006}, abstract = {The emission dynamics of a mode-locked laser oscillator with a nonlinear mirror based on stimulated Brillouin scattering (SBS) has been investigated with regard to its spectrum and to its intensity distribution. The investigation was carried out experimentally as well as by numerical simulations. The laser yields trains of pulses with measured durations of 410 ps and energies of the single pulse of up to 2 mJ. Two theoretical models describing the complex emission dynamics of a mode-locked SBS-laser oscillator are introduced. The first model consists of spectrally resolved laser rate equations and thus describes the mode locking in the frequency domain by the superposition of the longitudinal resonator modes. The SBS-Q-switch is incorporated by a phenomenological description of the time dependent SBS reflectivity. Numerical simulations based on this model yield the evolution of a few 100 longitudinal laser modes and the corresponding intensity distribution during the course of a Q-switch pulse with 10-ps resolution. The influences of the different components on the spectrum and thus on the pulse duration will be discussed. The second model describes all occurring dynamics in the time domain providing easy access to the study of misalignment on the output dynamics. Results of numerical simulations of both models and measurement results are compared}, language = {en} } @article{JechowLichtnerMenzeletal.2009, author = {Jechow, Andreas and Lichtner, Mark and Menzel, Ralf and Radziunas, Mindaugas and Skoczowsky, Danilo and Vladimirov, Andrei G.}, title = {Stripe-array diode-laser in an off-axis external cavity : theory and experiment}, issn = {1094-4087}, doi = {10.1364/OE.17.019599}, year = {2009}, abstract = {Stripe-array diode lasers naturally operate in an anti-phase supermode. This produces a sharp double lobe far field at angles {\~n}a depending on the period of the array. In this paper a 40 emitter gain guided stripe-array laterally coupled by off-axis filtered feedback is investigated experimentally and numerically. We predict theoretically and confirm experimentally that at doubled feedback angle 2a a stable higher order supermode exists with twice the number of emitters per array period. The theoretical model is based on time domain traveling wave equations for optical fields coupled to the carrier density equation taking into account diffusion of carriers. Feedback from the external reflector is modeled using Fresnel integration.}, language = {en} } @article{EichlerHaaseMenzeletal.1994, author = {Eichler, Hans Joachim and Haase, Alfred and Menzel, Ralf and Schwartz, J.}, title = {Depolarization treatment and optimization of high power double pass neodym-rod amplifiers with SBS mirror}, year = {1994}, language = {en} } @article{EichlerHaaseMenzel1994, author = {Eichler, Hans Joachim and Haase, Alfred and Menzel, Ralf}, title = {SBS-Phase Conjugation for Thermal Lens Compensation in 100 Watt Average Power Solid-State Lasers}, year = {1994}, language = {en} } @article{LueckMenzelSander1994, author = {Lueck, H. and Menzel, Ralf and Sander, Rolf}, title = {Inherent sample heating and temperature calibration in excited state absorption (ESA) measurements between room temperature and 77 kelvin}, year = {1994}, language = {en} } @article{EichlerMacdonaldMenzeletal.1995, author = {Eichler, Hans Joachim and Macdonald, R. and Menzel, Ralf and Sander, Rolf}, title = {Excited state absorption of 5CB (4'-n-pentyl-4-cyanobiphenyl) in cyclohexane}, year = {1995}, language = {en} } @article{EichlerMenzelSanderetal.1995, author = {Eichler, Hans Joachim and Menzel, Ralf and Sander, Rolf and Schulzke, M. and Schwartz, J.}, title = {SBS at different wavelengths between 308 and 725 nm}, year = {1995}, language = {en} } @article{EichlerHaaseMenzel1995, author = {Eichler, Hans Joachim and Haase, Alfred and Menzel, Ralf}, title = {Power enhancement and application of a Nd:YALO rod amplifier with a phase conjugating mirror}, year = {1995}, language = {en} } @article{MenzelEichlerGeinitzetal.1995, author = {Menzel, Ralf and Eichler, Hans Joachim and Geinitz, E. and Haase, Alfred and Scherrer, R.}, title = {Neodymium-laser with SBS phase conjugation for high beam quality}, year = {1995}, language = {en} } @article{EichlerHaaseMenzel1995, author = {Eichler, Hans Joachim and Haase, Alfred and Menzel, Ralf}, title = {Power enhancement and application of a Nd:YALO rod amplifier with a phase conjugating mirror}, year = {1995}, language = {en} } @article{EichlerHaaseMenzel1995, author = {Eichler, Hans Joachim and Haase, Alfred and Menzel, Ralf}, title = {100 watt average output power 1.2*diffraction limited beam from pulsed neodym single rod amplifier with SBS- phaseconjugation}, year = {1995}, language = {en} } @article{HeuerMenzelOstermeyer1996, author = {Heuer, Axel and Menzel, Ralf and Ostermeyer, Martin}, title = {Power tunable Nd-oscillators with diffraction limited beams via SBS phase conjugation}, year = {1996}, language = {en} } @article{OstermeyerHeuerMenzel1996, author = {Ostermeyer, Martin and Heuer, Axel and Menzel, Ralf}, title = {Q-switching of Nd-lasers with high repetition rates by SBS phase conjugation}, year = {1996}, language = {en} } @article{OstermeyerHeuerWatermannetal.1996, author = {Ostermeyer, Martin and Heuer, Axel and Watermann, V. and Menzel, Ralf}, title = {Resonators with phase conjugating SBS-mirror for solid state lasers with high output powers}, year = {1996}, language = {en} } @article{OstermeyerHeuerWatermannetal.1996, author = {Ostermeyer, Martin and Heuer, Axel and Watermann, V. and Menzel, Ralf}, title = {Single rod Nd:laser with phase conjugating SBS-mirror and large transversal mode for average output powers above 20 Watts}, year = {1996}, language = {en} } @article{SanderHerrmannMenzel1996, author = {Sander, Rolf and Herrmann, V. and Menzel, Ralf}, title = {Transient absorption spectra and bleaching of 4'-n-Pentyl-4-Cyanoterphenyl in Cyclohexane : determination of cross sections and recovery times}, year = {1996}, language = {en} } @article{EichlerHaaseMenzel1996, author = {Eichler, Hans Joachim and Haase, Alfred and Menzel, Ralf}, title = {High beam quality of a single rod neodym amplifier by SBS-phase conjugation up to 140 watt average output}, year = {1996}, language = {en} } @article{OstermeyerMenzel1997, author = {Ostermeyer, Martin and Menzel, Ralf}, title = {34 Watt flash lamp pumped single rod ND:YAG laser with 1.2 * DL beam quality via special resonator design}, year = {1997}, language = {en} } @article{HeuerHodgsonLorenzetal.1997, author = {Heuer, Axel and Hodgson, N. and Lorenz, Dieter and Ostermeyer, Martin and Menzel, Ralf}, title = {Solid state lasers with high brightness via optical phase conjugation for micromachining}, year = {1997}, language = {en} } @article{MittlerOstermeyerHeueretal.1997, author = {Mittler, Kay and Ostermeyer, Martin and Heuer, Axel and Menzel, Ralf}, title = {Longitudinal mode structure of Nd-lasers with phase conjugating mirrors based on stimulated Brillouin scattering in different materials}, year = {1997}, language = {en} } @article{OstermeyerLorenzMenzel1997, author = {Ostermeyer, Martin and Lorenz, Dieter and Menzel, Ralf}, title = {Nd-laser oscillators with phase-conjugating SBS mirrors for high average output powers and fundamental mode operation}, year = {1997}, language = {en} } @article{OstermeyerLorenzHodgsonetal.1997, author = {Ostermeyer, Martin and Lorenz, Dieter and Hodgson, N. and Menzel, Ralf}, title = {Transverse Modes in Laser Resonators with Phase Conjugating Mirror Based on Stimulated Brillouin Scattering (SBS)}, year = {1997}, language = {en} } @article{LorenzMenzel1998, author = {Lorenz, Dieter and Menzel, Ralf}, title = {Broadband operation of frequency doubled Cr4+:YAG laser with high beam quality}, year = {1998}, language = {en} } @article{MenzelOstermeyer1998, author = {Menzel, Ralf and Ostermeyer, Martin}, title = {Fundamental mode determination for guaranteeing diffrraction limited beam quality of lasers with high output powers}, year = {1998}, language = {en} } @article{OstermeyerHeuerMenzel1998, author = {Ostermeyer, Martin and Heuer, Axel and Menzel, Ralf}, title = {27 Watt average output power with 1.2*DL beam quality from a single rod Nd:YAG-Laser with phase conjugating SBS- mirror}, year = {1998}, language = {en} } @article{OstermeyerHodgsonMenzel1998, author = {Ostermeyer, Martin and Hodgson, N. and Menzel, Ralf}, title = {High-power, fundamental mode Nd:YALO laser using a phase-conjugate resonator based on SBS}, year = {1998}, language = {en} } @article{HeuerHodgsonMenzel1998, author = {Heuer, Axel and Hodgson, N. and Menzel, Ralf}, title = {Efficient, low-threshold phase conjugation in a tapered optical fiber}, year = {1998}, language = {en} } @article{HeuerMenzel1998, author = {Heuer, Axel and Menzel, Ralf}, title = {Phase conjugating SBS-mirror for low powers and reflectivities above 90 \% in an internally tapered optical fiber}, year = {1998}, language = {en} } @article{HeuerSchultheissHodgsonetal.1999, author = {Heuer, Axel and Schultheiss, J. and Hodgson, N. and Kurths, J{\"u}rgen and Menzel, Ralf and Raab, Volker}, title = {Transverse effects in phase conjugate laser mirrors based on stimulated brillouin scattering}, year = {1999}, language = {en} } @article{LorenzBrandenburgMenzel1999, author = {Lorenz, Dieter and Brandenburg, Ingo and Menzel, Ralf}, title = {Spectral broadening of the laser spectrum of gain-switched Ti:sapphire laser with nonlinear absorbers}, year = {1999}, language = {en} } @article{MittlerLorenzMenzel1999, author = {Mittler, Kay and Lorenz, Dieter and Menzel, Ralf}, title = {Broadband operation of a gain-switched Ti:sapphire laser for measurements with the coherence radar}, issn = {0277-786X}, year = {1999}, language = {en} } @article{MittlerLorenzMenzel1999, author = {Mittler, Kay and Lorenz, Dieter and Menzel, Ralf}, title = {Time-resolved measurements of the spectra of a broadband laser used as light source for the coherence radar}, year = {1999}, language = {en} } @article{OstermeyerMittlerMenzel1999, author = {Ostermeyer, Martin and Mittler, Kay and Menzel, Ralf}, title = {Q switch and longitudinal modes of a laser oscillator with a stimulated-Brillouin-scattering mirror}, year = {1999}, language = {en} } @article{OstermeyerMenzel1999, author = {Ostermeyer, Martin and Menzel, Ralf}, title = {Single rod efficient Nd:YAG and Nd:YALO-lasers with average output powers of 46 and 47 W in diffraction limited beams with M2 < 1.2 and 100 W with M2 < 3.7}, year = {1999}, language = {en} } @article{OstermeyerMenzel1999, author = {Ostermeyer, Martin and Menzel, Ralf}, title = {50 Watt average output power with 1.2*DL beam quality from a single rod Nd:YALO laser with phase-conjugating SBS mirror}, year = {1999}, language = {en} } @article{MittlerLorenzMenzel1999, author = {Mittler, Kay and Lorenz, Dieter and Menzel, Ralf}, title = {Time resolved emission spectra of a broadband ns-laser with 0.5 W average output power used as light source for the coherence radar}, year = {1999}, language = {en} } @article{LorenzMittlerBrandenburgetal.2000, author = {Lorenz, Dieter and Mittler, Kay and Brandenburg, Ingo and Menzel, Ralf}, title = {Enhanced coherence radar measurements with spectrally broadened Ti:sapphire laser using nonlinear absorber}, isbn = {08194-3546-5}, year = {2000}, abstract = {D. Lorenz, K. Mittler, I. Brandenburg, R. Menze}, language = {en} } @article{HeuerMenzel2000, author = {Heuer, Axel and Menzel, Ralf}, title = {Temporal features of SBS phase conjugation}, isbn = {0-8194-3545-7}, year = {2000}, language = {en} }