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31.
32.
Optical Fano resonances due to resonant eigenmodes in a layered periodically-modulated structure (photonic crystal slab) are
investigated theoretically. The special attention is focused on the behavior of the resonances near a diffraction threshold.
A new formulation of the resonant mode approximation for the optical scattering matrix near the diffraction threshold anomalies
is proposed. 相似文献
33.
Search for a standard model Higgs boson in the H→ZZ→ℓ(+)ℓ(-)νν decay channel with the ATLAS detector
Aad G Abbott B Abdallah J Abdelalim AA Abdesselam A Abdinov O Abi B Abolins M Abramowicz H Abreu H Acerbi E Acharya BS Adams DL Addy TN Adelman J Aderholz M Adomeit S Adragna P Adye T Aefsky S Aguilar-Saavedra JA Aharrouche M Ahlen SP Ahles F Ahmad A Ahsan M Aielli G Akdogan T Åkesson TP Akimoto G Akimov AV Akiyama A Alam MS Alam MA Albert J Albrand S Aleksa M Aleksandrov IN Alessandria F Alexa C Alexander G Alexandre G Alexopoulos T Alhroob M Aliev M Alimonti G Alison J Aliyev M Allport PP 《Physical review letters》2011,107(22):221802
A search for a heavy standard model Higgs boson decaying via H→ZZ→→?(+)?(-)νν, where ?=e, μ, is presented. It is based on proton-proton collision data at √s=7 TeV, collected by the ATLAS experiment at the LHC in the first half of 2011 and corresponding to an integrated luminosity of 1.04 fb(-1). The data are compared to the expected standard model backgrounds. The data and the background expectations are found to be in agreement and upper limits are placed on the Higgs boson production cross section over the entire mass window considered; in particular, the production of a standard model Higgs boson is excluded in the region 340相似文献
34.
35.
V. A. Akimov M. P. Frolov Y. V. Korostelin V. I. Kozlovsky A. I. Landman Y. P. Podmar’kov Y. K. Skasyrsky A. A. Voronov 《Applied physics. B, Lasers and optics》2009,97(4):793-797
We report the spectroscopic characteristics and laser properties of Cr2+:CdS. The emission lifetime of the exited state, 5E, of Cr2+ in CdS host was measured to be 0.93 μs at room temperature and 7.3 μs at liquid nitrogen temperature. The measured values
of peak absorption and emission cross sections were found to be 1.4×10−18 and 1.1×10−18 cm2 respectively. Room-temperature pulsed-laser operation was obtained under pumping by the 1.94 μm output of a Tm:YAP laser.
The output of the free-running Cr2+:CdS laser was centered at ∼2.6 μm, and an absorbed energy slope efficiency of 38.8% was demonstrated. The passive crystal
losses were measured to be less than 0.049 cm−1 at the lasing wavelength. With an intracavity prism, the Cr2+:CdS laser was tuned from 2.18 to 3.32 μm. 相似文献
36.
D.A. Akimov T. Siebert A.M. Zheltikov W. Kiefer 《Applied physics. B, Lasers and optics》2006,83(2):185-187
A blue-shifted output of a photonic-crystal fiber, providing a frequency upconversion of femtosecond Ti:sapphire laser pulses, is used to seed a double-pass optical parametric oscillator (OPA). The OPA is based on a BBO crystal, pumped by 65-mW 150-fs second-harmonic pulses of a Ti:sapphire laser. Gain factors in excess of 103 are demonstrated for such an OPA, yielding tunable light pulses within the range of wavelengths from 420 to 650 nm, a peak power up to 250 kW, and a typical pulse width of about 200 fs at a repetition rate of 100 kHz. PACS 42.81.Gs; 42.81.Qb 相似文献
37.
The stability of high‐frequency potential surface waves at a dense magnetized plasma – metal interface with respect to a low‐frequency plasma density modulation is studied in the point of view of the surface waves control. The discussion is addressed to the situation, when an external steady magnetic field is directed perpendicularly to the interface. The nonlinear interaction process of the high‐frequency surface wave, its satellites and the low‐frequency plasma density perturbation is investigated. It is shown that the low‐frequency plasma density perturbation can be represented as a superposition of forced waves of surface and volume types and can lead to an additional attenuation of the surface waves. This attenuation arises when the surface wave amplitude exceeds the threshold value. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
38.
We propose a numerical approach to quantify the control of a nonautonomous molecular rotor motion. Unlike straightforward molecular dynamics simulations in an explicitly time-dependent framework, our method is based on the theory of geometric phases. This theory allows us to define a sensitivity field (SF) in control parameter space that characterizes average motion of a molecule induced by a cyclic perturbation. We show that the SF can be obtained using only equilibrium free energy sampling techniques. A density plot of the SF quantifies response of a molecule to an arbitrary cyclic adiabatic evolution of parameters. For demonstration, we numerically find the SFs for two surface mounted molecular rotor molecules that can be driven, in practice, by strong time-dependent electric fields of a STM tip. 相似文献
39.
E. Ya. Misochko A. V. Akimov A. A. Masitov D. V. Korchagin S. M. Aldoshin S. E. Boganov K. N. Shavrin V. D. Gvozdev M. P. Egorov O. M. Nefedov 《Russian Chemical Bulletin》2011,60(11):2180-2187
The ESR spectrum of the first representative of highly conjugated triplet ethynylvinylcarbenes, 5-methylhexa-1,2,4-triene-1,3-diyl (1), was recorded in solid argon matrix. The zero-field splitting (ZFS) parameters of carbene 1 (D = 0.5054±0.0006 cm?1 and E = 0.0045±0.0002 cm?1) determined from the experimental ESR spectrum are in between the corresponding parameters of ethynylcarbene C3H2 (2) and vinylcarbene C3H4 (3): D(3) < D(1) < D(2) and E(2) < E(1) < E(3). Quantum chemical calculations of the ZFS parameters of 1, 2, and 3 have been carried out for the first time using two DFT-based approaches, RODFT and UDFT. An analysis of the experimental and theoretical ZFS parameters shows that carbene 1 is characterized by a greater extent of delocalization of the spin density of unpaired electrons than carbenes 2 and 3. The characteristic structural fragments of carbene 1 possess the principal features of the electronic structure of both ethynylcarbene (2) and vinylcarbene (3), respectively. Magnetic spin-spin interactions are identical in carbenes 1 and 2. The dominant contribution to D in 1 and 2 results from the one-center spin-spin interactions on carbon atoms in the propynylidene group, which are subjected to strong spin polarization. 相似文献
40.
Mikhail Y. Shalaginov Vadim V. Vorobyov Jing Liu Marcello Ferrera Alexey V. Akimov Alexei Lagutchev Andrey N. Smolyaninov Vasily V. Klimov Joseph Irudayaraj Alexander V. Kildishev Alexandra Boltasseva Vladimir M. Shalaev 《Laser \u0026amp; Photonics Reviews》2015,9(1):120-127
The broadband enhancement of single‑photon emission from nitrogen‐vacancy centers in nanodiamonds coupled to a planar multilayer metamaterial with hyperbolic dispersion is studied experimentally. The metamaterial is fabricated as an epitaxial metal/dielectric superlattice consisting of CMOS‐compatible ceramics: titanium nitride (TiN) and aluminum scandium nitride (AlxSc1‐xN). It is demonstrated that employing the metamaterial results in significant enhancement of collected single‑photon emission and reduction of the excited‐state lifetime. Our results could have an impact on future CMOS‐compatible integrated quantum sources.