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131.
W. Shuicai H. Junfang X. Dong Z. Changjun H. Xun 《Applied physics. B, Lasers and optics》2001,72(7):819-821
We have constructed a three-wavelength Ti:sapphire femtosecond laser with an independent tunable wavelength (λ1) and two variable central wavelengths (λ2 and λ3) for use with the multi-excited photosystem II. Stable sub-40-fs pulses are generated. The λ1-wavelength pulses can be tuned independently from 750 nm to 850 nm. The center wavelengths λ2 and λ3 can be varied from 760 nm to 840 nm.
Received: 14 April 2000 / Revised version: 5 September 2000 / Published online: 27 April 2001 相似文献
132.
We propose a mode-locked figure-eight fiber laser by utilizing an attenuation-imbalanced nonlinear optical loop mirror (AI-NOLM) for the first time. Stable self-starting passively mode-locked pulses as short as 296 fs are obtained. We have also confirmed that the pulse width of the laser can be varied by changing the amount of attenuation in the AI-NOLM. 相似文献
133.
A Fabry–Perot semiconductor saturable absorber has been implemented in a colliding pulse configuration for stabilizing a harmonically
mode-locked fiber laser. An environmentally stable CPM design is shown to enhance supermode suppression.
Received: 24 October 2000 / Revised version: 28 November 2000 / Published online: 9 February 2001 相似文献
134.
Correlation between Zero-Field Splitting and Site Distortions of Cr^3+ Ions in NH4Cl:Cr^3+ System: a Complete Energy Matrix Study 下载免费PDF全文
A theoretical method for investigating the inter-relation between the electronic and molecular structures of 3d^3 configuration ions in a tetragonal ligand field is established on the basis of the 120 × 120 complete energy matrices. Using this method, the local structure parameters of two tetragonal Cr^3+ centers in the NH4 Cl:Cr^3+ system are determined, Furthermore, the relations between the molecular symmetry and the ligand field symmetry are discussed. 相似文献
135.
Andreas Schmidt Huaijin Zhang Minhua Jiang Valentin Petrov 《Optics Communications》2010,283(4):567-569
Passive mode-locking using a SESAM is demonstrated for the Yb-doped cubic non-stoichiometric crystal CNGG which exhibits local disorder. The pulse duration of 73 fs obtained is the shortest for an isotropic Yb-doped laser crystal while larger output coupling resulted in average output powers of 750 mW with 66% efficiency in the mode-locked regime. 相似文献
136.
137.
T.W. Carr T. Erneux 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,17(1):67-74
We consider the rate equations for a laser with an intracavity saturable absorber and subject to a periodically modulated
pump. By deriving simplified equations for a map valid for strongly pulsating regimes, analytical conditions are determined
that specify the properties of both frequency-locked and unlocked behaviors. As the strength of the modulation is increased,
quasiperiodic and period-doubling bifurcations are predicted. However, only the transition from locking to non-locking through
a quasiperiodic bifurcation is possible for realistic values of the parameters. Our results are consistent with previous numerical
and experimental studies of modulated lasers with a saturable absorber.
Received 10 March 2001 相似文献
138.
The g factor of Cr4+ in Y2SiO5 crystal is calculated from a completed high-order perturbation formula, in which not only the conventional contribution to the g-shift Δg(=g−ge) from the crystal-field mechanism, but also the contribution from the charge-transfer mechanism (which is neglected in the crystal-field theory) are considered. The calculated result shows good agreement with the observed value. It is found that the calculated Δg due to the charge-transfer mechanism is opposite in sign and about 38% in magnitude, compared with that due to the crystal-field mechanism. So, in the studies of the g factor for a 3dn ion having high valence state in crystals, the contribution due to the charge-transfer mechanism should be taken into account. 相似文献
139.
J.D. Pedarnig H. Göttlich R. Rössler W.M. Heckl D. Bäuerle 《Applied Physics A: Materials Science & Processing》1998,67(4):403-405
2 Cu3O7-δ films have been patterned by means of an arrangement employed in scanning near-field optical microscopy (SNOM). Standard
SNOM probes were modified to achieve high transmission for direct writing by oxygen depletion in N2 atmosphere. The written lines are about 1.5 μm wide and show a semiconductor-like resistivity behavior (δ≥0.5). The morphology
of illuminated regions is about the same as that of the YBCO films.
Received: 3 July 1998/Accepted: 6 July 1998 相似文献
140.
R. Prazeres F. Glotin C. Insa D.A. Jaroszynski J.M. Ortega 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,3(1):87-93
The two-colour operation of a Free-Electron Laser (FEL) has been demonstrated with the “CLIO” infrared facility. A two section
undulator allows the production of picosecond laser pulses at two different wavelengths and simultaneously, in a wavelength range from to , and with a wavelength separation of two colours of up to . The time overlap, between both colours, has been measured on a picosecond time scale and on a microsecond time scale. An
initial pump-probe application experiment has been performed with the two colours: stimulated emission has been measured in
a 3-level Quantum-Well system. This is the best demonstration of the stability and reliability of the two-colour laser operation.
Received: 4 November 1997 / Revised in final form: 31 March 1998 / Accepted: 10 April 1998 相似文献