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91.
D. G. Middleton J. R. M. Annand C. Barbieri P. Barneo P. Bartsch D. Baumann J. Bermuth D. Bosnar H. P. Blok R. Böhm M. Ding M. O. Distler D. Elsner J. Friedrich C. Giusti D. I. Glazier P. Grabmayr S. Grözinger T. Hehl J. Heim W. H. A Hesselink E. Jans F. Klein M. Kohl L. Lapikás I. J. D. MacGregor I. Martin J. C. McGeorge H. Merkel P. Merle F. Moschini U. Müller Th. Pospischil G. Rosner H. Schmieden M. Seimetz A. Süle H. de Vries Th. Walcher D. P. Watts M. Weis B. Zihlmann 《The European Physical Journal A - Hadrons and Nuclei》2006,30(2):469-469
92.
We present a photonic crystal fiber (PCF)-based light source for generating tunable excitation pulses (pump and Stokes) that are applicable to coherent anti-Stokes Raman scattering (CARS) microspectroscopy. The laser employed is an unamplified Ti:sapphire femtosecond laser oscillator. The CARS pump pulse is generated by spectral compression of a laser pulse in a PCF. The Stokes pulse is generated by redshifting a laser pulse in a PCF through the soliton self-frequency shift. This setup allows for probing up to 4000 cm(-1) with a spectral resolution of approximately 25 cm(-1). We characterize the stability and robustness of CARS microspectroscopy employing this light source. 相似文献
93.
D. Reuter V. Stavarache A.D. Wieck M. Schwab R. Oulton M. Bayer 《Physica E: Low-dimensional Systems and Nanostructures》2006,32(1-2):73
We have performed single dot photoluminescence and time-resolved ensemble photoluminescence measurements on InAs quantum dots embedded in a lateral in-plane p–i–n or n–i–n device, respectively, which makes the application of lateral electric fields, i.e. field direction perpendicular to the growth direction, feasible. Time-resolved measurements show an increase in the radiative lifetime of up to 30% with increasing field. We attribute this to the reduced overlap between the electron and hole wave functions. Single dot spectroscopy revealed a small red-shift of the emission energies of maximum 0.5 meV. This shift can be explained by the quantum confined Stark effect taking into account that the red-shift due to the band-tilting is partly compensated by a decrease in exciton binding energy. 相似文献
94.
D. Kocheva G. Rainovski J. Jolie N. Pietralla A. Blazhev A. Astier R. Altenkirch S. Ansari Th. Braunroth M. L. Cortés A. Dewald F. Diel M. Djongolov C. Fransen K. Gladnishki A. Hennig V. Karayonchev J. M. Keatings E. Kluge J. Litzinger C. Müller-Gatermann P. Petkov M. Rudigier M. Scheck Ph. Scholz P. Spagnoletti M. Spieker C. Stahl R. Stegmann M. Stoyanova P. Thöle N. Warr V. Werner W. Witt D. Wölk K. O. Zell P. Van Isacker V. Yu. Ponomarev 《The European Physical Journal A - Hadrons and Nuclei》2017,53(9):175
95.
Interferometry with Ca atoms 总被引:1,自引:0,他引:1
Separated field excitation of a calcium atomic beam using four traveling laser fields represents two distinct atom interferometers utilizing the internal degrees of freedom of the atoms. Phase shifts between the atomic partial waves have been realized by phase shifts of the laser wave fields, by the ac-Stark shift, and by rotation of the interferometer (Sagnac effect). One particular interferometer can be selected by interaction of the atomic waves with extra laser fields. We furthermore report on the preparation of a laser cooled and deflected calcium atomic beam that can be utilized to largely increase the sensitivity of the interferometer. 相似文献
96.
Polymer lightguides of PMMA doped with the azo dyes methyl-red and N, N-dihexyl-4-amino-4'-nitro-azobenzene (DHANA) are investigated with respect to their opto-optical properties. The trans-cis photoisomerisation of the dyes leads to reversible polarization-dependent optically induced refractive index changes. The index changes are anisotropic. Birefringence is measured using index matched lightguides. The changes with respect to each polarization are determined by leaky mode spectroscopy and by using a half-integrated interferometer. These changes are intensity dependent and, with a suitable geometry, bistability at low intensities (3 mW/mm3) can be obtained. 相似文献
97.
M. Begalli F. Botterweck H. Boettcher M. Charlet P. V. Chliapnikov E. A. De Wolf K. Dziunikowska A. M. F. Endler A. Eskreys W. Friebel G. R. Gulkanyan Z. S. Garutchava W. Kittel S. S. Megrabyan Th. Naumann K. Olkiewicz H. E. Roloff O. G. Tchikilev L. A. Tikhonova A. G. Tomaradze F. Verbeure R. Wischnewski S. A. Zotkin 《Zeitschrift fur Physik C Particles and Fields》1992,55(4):531-538
Results on the multiplicity structure of diffractively excited meson and proton systems in À+/K+
p interactions at 250 GeV/c are presented for diffractive masses up to about 9 GeV. The energy dependence of the average charge multiplicity and the shape of the multiplicity distribution in terms of KNO-scaling and negative binomial distribution are investigated. The diffractive systems are compared toe
+
e
–,lh and non-diffractivehh final states as suggested by modern approaches of the Pomeron-hadron collision. Systematic differences are found between diffractive meson and proton systems but also between diffraction and the reactions compared to. 相似文献
98.
D. I. Glazier M. Seimetz J. R. M. Annand H. Arenhövel M. Ases Antelo C. Ayerbe P. Bartsch D. Baumann J. Bermuth R. Böhm D. Bosnar M. Ding M. O. Distler D. Elsner J. Friedrich S. Hedicke P. Jennewein G. Jover Ma nas F. H. Klein F. Klein M. Kohl K. W. Krygier K. Livingston I. J. D. MacGregor M. Makek H. Merkel P. Merle D. Middleton U. Müller R. Neuhausen L. Nungesser M. Ostrick R. Pérez Benito J. Pochodzalla Th. Pospischil M. Potokar A. Reiter G. Rosner J. Sanner H. Schmieden A. Süle Th. Walcher D. P. Watts M. Weis 《The European Physical Journal A - Hadrons and Nuclei》2005,24(1):101-109
The electric form factor of the neutron, GE,n, has been measured at the Mainz Microtron by recoil polarimetry in the quasielastic D(¯e, e¯n)p reaction. Three data points have been extracted at squared four-momentum transfers Q
2 = 0.3, 0.6 and 0.8 (GeV/c)2. Corrections for nuclear binding effects have been applied.This revised version was published online in March 2005. In the previous version, the email address of one author was inadvertently assigned to multiple authors. 相似文献
99.
R. Matthey S. Schilt D. Werner C. Affolderbach L. Thévenaz G. Mileti 《Applied physics. B, Lasers and optics》2006,85(2-3):477-485
We describe a low-power continuous-wave laser system for water-vapour sensing applications in the 935-nm region. The system is based on extended-cavity diode lasers and distributed-feedback lasers and delivers four single-mode frequency-stabilised optical signals. Three lasers are locked to three water-vapour absorption lines of different strengths, whereas the fourth lies outside any absorption line. On-line stabilisation is performed by wavelength-modulation spectroscopy using compact water-vapour reference cells. An offset-locking technique implemented around an electrical filter is applied for the stabilisation of the off-line slave laser to an on-line master laser at a frequency detuning of 18.8 GHz. Stabilities in the order of 15 MHz over one day were observed for the strongest lines, at the detection limit of the measurement instrumentation. The developed techniques and schemes can be applied to other wavelength ranges and molecular species. Differential absorption lidar instrumentation can in particular benefit from such a system when the stabilised lasers serve as injection seeders to pulsed power oscillators. PACS 42.62.Fi; 42.72.-g; 42.68.Wt 相似文献
100.
Q. Luo H.L. Xu S.A. Hosseini J.-F. Daigle F. Théberge M. Sharifi S.L. Chin 《Applied physics. B, Lasers and optics》2006,82(1):105-109
The fluorescence spectrum of ethanol molecules induced by femtosecond laser pulses has been recorded as the fingerprint of
the molecules. It was demonstrated that, if this is combined with a LIDAR technique, the fluorescence from pollutants in the
atmosphere could be detected over a long distance.
PACS 42.68.Wt; 42.62.Fi; 42.65.Re 相似文献