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H. Schmidt T. Fleischer B. Sumpf A. Szczerbakow Ka. Herrmann J. W. Tomm 《Crystal Research and Technology》1991,26(6):757-766
Results on applied infrared photoluminescence investigations of lead salt chalcogenides are presented. Interpretations of spectra and wafer maps are given. The results obtained may be applied to the investigation of material properties important for laser and detector fabrication. 相似文献
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The preparation and the influence of low ohmic multilayer thin film contacts of lead-salt homo- and heterolasers on the degradation of lasing parameters during recycling processes between low working temperatures and room temperatures storage are described and discussed in detail. 相似文献
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B. Sumpf J.P. Burrows A. Kissel H.-D. Kronfeldt O. Kurtz I. Meusel J. Orphal S. Voigt 《Journal of Molecular Spectroscopy》1998,190(2):226-231
Line shift coefficients for five lines of five different isotopomers in the fundamental band of CO in the spectral region near 2058 cm−1were measured using a three channel lead salt diode laser spectrometer. The study includes the linesP(3) of13C17O,R(3) of13C18O,P(9) of12C18O,P(10) of13C16O, andP(21) of12C16O, and covers collisions with N2, O2, H2, D2, He, Ne, Ar, Kr, and Xe. Line shifts of the isotopomers13C16O,12C18O,13C18O, and13C17O were determined for the first time. Within the experimental uncertainty no significant dependence of the shift effect on the isotopomer was found. TheR-branch line under study shows a smaller line shift coefficient than aP-branch line with a similar rotational quantum number. With increasing mass of the noble gas perturber the absolute size of the shift coefficient increases. Moreover self- and nitrogen-broadening coefficients for the isotopomer lines were determined. Compared to previous measurements no significant deviations between different isotopomers were observed. 相似文献
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Sumpf B. Hülsewede R. Erbert G. Dzionk C. Fricke J. Knauer A. Pittroff W. Ressel P. Sebastian J. Tränkle G. 《Optical and Quantum Electronics》2003,35(4-5):521-532
High brightness tapered laser diodes with different resonator geometries were fabricated and analysed. The devices consist of an index-guided straight section and a gain-guided tapered section. Lasers with a total length L = 2 and 4 mm and different length of the ridge waveguide L RW (500 μm ≤ L RW ≤ 1250 μm for L = 2 mm and 500 μm ≤ L RW ≤ 2000 μm for L = 4 mm) were processed to study the influence of the straight section on the spatial mode filtering. The power–voltage–current-characteristics, the beam waist, the far field, and the beam propagation factor M 2 were measured. From the experiments, it can be stated that the lasers with a small L RW reach higher output powers compared to those with larger L RW. Concerning the beam quality the length L RW should exceed a minimal value to guarantee efficient spatial mode filtering. Devices optimised concerning maximum output power and excellent beam quality reach a beam propagation factor smaller than 2.1 at an output power P = 2 W. 相似文献
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B. Sumpf T. Kelz M. Nägele H.-D. Kronfeldt 《Applied physics. B, Lasers and optics》1997,64(5):521-524
2 and two diode lasers as pump sources and experiments with this setup are presented. In contrast to the majority of known
applications of the difference frequency mixing with solid state or gas lasers, we apply two single mode diode lasers with
emission wavelengths of 690 nm and 805 nm, respectively. By fixing the emission wavelength of one diode laser and tuning the
wavelength of the second laser, by changing temperature or excitation current, we can cover typically 0.87 cm-1 (FWHM) in good agreement with recently published data and theory. With an input power of 20 mW and 6 mW we achieved an output
power in the nW-range. To demonstrate the capabilities of the spectrometer we scanned CO and OCS absorption lines near 2107 cm-1. From these experiments we deduce an overall signal-to-noise ratio of 1000:1 and a spectral resolution better than 30 MHz.
With such parameters a trace gas detection of CO at sub-ppm level will be possible.
Received: 19 August 1996/Revised version: 5 November 1996 相似文献
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A KisselB Sumpf H.-D KronfeldtB.A Tikhomirov Yu.N Ponomarev 《Journal of Molecular Spectroscopy》2002,216(2):345-354
The pressure-induced shift and broadening of H2S absorption lines in the ν2-band due to collisions between H2S molecules and quadrupole molecules, such as O2, H2, D2, N2, and CO2, were studied in the spectral region between 1050 and 1325 cm−1. The measurements were carried out using a pulse-driven diode laser spectrometer with two multipass Herriott cells. The data concerning the collisional broadening and shift coefficients, γ and δ, respectively, and their dependencies on the rotational quantum number J″ and the quadrupole moment Q of the molecular perturber are presented for 14 P-branch transitions (3≤J″≤8,0≤KaPrime;≤3, 2≤KcPrime;≤8), 7 Q-branch transitions (7≤JPrime;≤10, 1≤KaPrime;≤2, 6≤KcPrime;≤9), and 18 R-branch transitions (2≤JPrime;≤11, 0≤KaPrime;≤4, 0≤KcPrime;≤11). The broadening coefficients γ were determined with an accuracy to within 2% and shift coefficients δ were determined with an uncertainty of less than 10−3 cm−1/atm for the majority of lines and broadening gases. 相似文献
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2 and two diode lasers as pump sources are presented. A single-mode Fabry–Pérot-type tunable diode laser (TDL) and an external-cavity
diode laser (ECL) were combined to generate radiation in the mid-infrared region near 7.2 μm. With a TDL at a wavelength of
approximately 1290 nm and an ECL emitting between 1504 and 1589 nm it was possible to carry out spectroscopic experiments
concerning SO2 at five different phasematching points between 1350 and 1400 cm-1 by fixing the wavelength of one pump laser and tuning the wavelength of the other. With an input power of 8 mW for the single-mode
Fabry–Pérot-type diode laser and 6 mW for the external-cavity laser an output power of about 10 nW was generated. Using the
tuning capabilities of the external-cavity laser a spectral region up to 5 cm-1 could be covered within one scan. Measurements of SO2 absorption lines at low pressure demonstrate the high-resolution features of the spectrometer. Moreover, these data provide
new direct experimental phasematching data for the rarely investigated spectral region at 7.2 μm.
Received: 27 October 1997/Revised version: 8 May 1998 相似文献
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Haynes Pak Hay Cheng Ole Bjarlin Jensen Peter Eskil Andersen Bernd Sumpf Christian Pedersen 《Optics Communications》2010,283(23):4717-20461
Using a tunable external cavity tapered diode laser (ECDL) pumped quasi-three-level Nd:YAG laser, a fivefold reduction in threshold and twofold increase in slope efficiency is demonstrated when compared to a traditional broad area diode laser pump source. A TEM00 power of 800 mW with 65% slope efficiency is obtained, the highest reported TEM00 power from any 946 nm Nd:YAG laser pumped by a single emitter diode laser pump source. A quantum efficiency of 0.85 has been estimated from experimental data using a simple quasi-three-level model. The reported value is in good agreement with published values, suggesting that the model is adequate. Improvement of the 946 nm laser due to the ECDL's narrow spectrum proves to be less significant when compared to its spatial quality, inferring a broad spectrum tapered diode laser pump source may be most practical. Experimental confirmation of such setup is given. 相似文献