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In this paper, we investigate the photon correlations and the statistical properties of light produced by an optical cavity with an embedded quantum well interacting with squeezed light. We show that the squeezed source substantially improves the intensity of the emitted light and generates a narrowing and a duplication of the spectrum peaks. With a strong dependence on frequency detuning, the cavity produces considerably squeezed radiation, and perfect squeezing is predicted for weak light–matter interactions. Furthermore, the system under consideration presents a bunching effect of the transmitted radiation resulting from weak pumping of the coherent field. The results obtained may have potential applications in the fields of very accurate measurement and quantum computing. 相似文献
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Conjugated dienes are obtained by coupling of alkenyl cuprates and alkenyl halides in the presence of ZnBr2 and a catalytic amount of PdoL4. 相似文献
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Jonas Bruckhuisen Guillaume Dhont Anthony Roucou Atef Jabri Hamdi Bayoudh Thi Thanh Tran Manuel Goubet Marie-Aline Martin-Drumel Arnaud Cuisset 《Molecules (Basel, Switzerland)》2021,26(12)
Catechol is an oxygenated aromatic volatile organic compound and a biogenic precursor of secondary organic aerosols. Monitoring this compound in the gas phase is desirable due to its appreciable reactivity with tropospheric ozone. From a molecular point of view, this molecule is attractive since the two adjacent hydroxy groups can interchangeably act as donor and acceptor in an intramolecular hydrogen bonding due to the tunnelling between two symmetrically equivalent structures. Using synchrotron radiation, we recorded a rotationally-resolved Fourier Transform far-infrared (IR) spectrum of the torsional modes of the free and bonded -OH groups forming the intramolecular hydrogen bond. Additionally, the room temperature, pure rotational spectrum was measured in the 70–220 frequency range using a millimeter-wave spectrometer. The assignment of these molecular transitions was assisted by anharmonic high-level quantum-chemical calculations. In particular, pure rotational lines belonging to the ground and the four lowest energy, vibrationally excited states were assigned. Splitting due to the tunnelling was resolved for the free -OH torsional state. A global fit combining the far-IR and millimeter-wave data provided the spectroscopic parameters of the low-energy far-IR modes, in particular those characterizing the intramolecular hydrogen bond dynamics. 相似文献
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The quantum noise and the squeezing effect, in the transmitted light, by a dipolariton system formed by a double quantum wells microcavity in the strong coupling regime are investigated. It is shown that the indirect exciton nonlinearity generates stronger squeezing than the direct exciton nonlinearity, nevertheless produces very high fluctuations for some particular detunings and nonlinearities. The system shows a considerable sensitivity to the thermal excitations where the coupling to the direct and indirect excitonic thermal baths progressively destroys the nonclassical effect. Despite that, indirect exciton squeezing manifests a higher resistance against the thermal bath temperature. As a result, the emission field is strongly governed by the indirect excitons, varying between robust squeezing and excess noise. 相似文献
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Jabri A Temple C Crewdson P Gambarotta S Korobkov I Duchateau R 《Journal of the American Chemical Society》2006,128(28):9238-9247
The reaction of the highly selective [CySCH2CH2N(H)CH2CH2SCy]CrCl3 catalyst precursor with alkyl aluminum activators was examined with the aim of isolating reactive intermediates. Reaction with Me3Al afforded a cationic trivalent chromium alkyl species {[CySCH2CH2N(H)CH2CH2SCy]CrMe(mu-Cl)}2{(AlMe3)2(m-Cl}2.(C7H8)2 (1a). Although it was not possible to obtain crystalline samples of sufficient quality from the reaction with MAO (the most preferred activator), the near-to-identical EPR spectra indicated a very close structural similarity with 1a. Ethylene oligomerization tests clearly revealed that 1 and other cationic trivalent dimeric complexes {[CySCH2CH2N(H)CH2CH2SCy] CrCl(mu-Cl)}2{AlCl4}2.(C7H8)1.5 (2), monomeric [(CySCH2CH2N(H)CH2CH2SCy)CrCl2 (THF)][AlCl4] (3), and {[CySCH2CH2N(H)CH2CH2SCy]Cr(eta2-AlCl4)}{Al2Cl7} (4) adducts display the same catalyst selectivity as the [CySCH2CH2N(H)CH2CH2SCy]CrCl3 complex and, therefore, are probably all precursors to the same catalytically active species. 2, 3, and 4 were obtained upon treatment of [CySCH2CH2N(H)CH2CH2SCy] CrCl3 with different stoichiometric ratios of AlCl3.. When i-BAO activator was used, reduction of the metal center occurred readily, affording {([CySCH2CH2N(H)CH2CH2S Cy]Cr)(mu-Cl)]2}{(i-Bu)2AlCl2}2 (5). 5 is also a selective catalyst, thus indicating that trivalent species are most probably precursors to a divalent catalytically active complex. Reaction of CrCl2(THF)2 with the ligand afforded the labile divalent adduct [CySCH2CH2N(H)CH2CH2SCy]CrCl2(THF) (6), also catalytically active and selective. Instead, deprotonation of the ligand with n-BuLi followed by reaction with CrCl2(THF)2 gave the dinuclear complex [(mu-CySCH2CH2NCH2CH2SCy)CrCl]2 (7), which did not produce oligomers. 相似文献
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Z dialkenyl cuprates couple easily with iodo arenes in the presence of ZnBr2 and a catalytic amount of Pd(PPh3)4. 相似文献
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Zegers RG van Den Berg AM Brandenburg S Fleurot FR Fujiwara M Guillot J Hannen VM Harakeh MN Laurent H van Der Schaaf K van Der Werf SY Willis A Wilschut HW 《Physical review letters》2000,84(17):3779-3782
The (nat)Pb(3He,tp) reaction at E(3He) = 177 MeV was studied to identify 2Planck's over 2piomega isovector monopole strength in Bi isotopes. Monopole strength was found in the region -45
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The dynamics of a single strain HIV model is studied.The basic reproduction number R_0 used as a bifurcation parameter shows that the system undergoes transcritical and saddle-node bifurcations.The usual threshold unit value of R_0 does not completely determine the eradication of the disease in an HIV infected person.In particular,a sub-threshold value R_C is established which determines the system's number of endemic states:multiple if R_c Ro 1,only one if R_C = R_0 = 1,and none if R_0 R_C 1. 相似文献