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861.
We present a scheme for linear optical quantum computation that is highly robust to imperfect single photon sources and inefficient detectors. In particular we show that if the product of the detector efficiency with the source efficiency is greater than 2/3, then efficient linear optical quantum computation is possible. This high threshold is achieved within the cluster state paradigm for quantum computation. 相似文献
862.
A frequency-selective REDOR experiment is described for SI2 spin systems. The experiment causes the net dipolar dephasing of the S spin to evolve only under the influence of one of the I spins. The experiment is based on a single pair of appropriately phased 90° I-spin pulses, and the I spin causing the S-spin dipolar dephasing is determined by the relative phases between the two 90° pulses. The experiment is demonstrated on a sample of 15N2-l-asparagine. 相似文献
863.
Vladislav Papper Yuanyuan Wu Vladimir Kharlanov Ayrine Sukharaharja Terry W. J. Steele Robert S. Marks 《Journal of fluorescence》2018,28(1):13-19
N,N-dimethyl-N′-picryl-4,4′-stilbenediamine (DMPSDA) was prepared, purified and crystallised in a form of black lustrous crystals, and its absorption and fluorescence spectra were recorded in cyclohexane, acetonitrile and dimethyl sulfoxide. Non-emissive intramolecular charge transfer state (ICT) was clearly observed in this molecule in all three solvents. Theoretical calculations demonstrating a betaine electronic structure of the trinitrophenyl group in the ground state of the molecule and a charge transfer nature of the long wavelength transition S0?→?S1 supported the experimental observations of the ICT formation in the molecule. 相似文献
864.
The structures of eleven different metallocenes substituted with either methyl and/or t-butyl groups were minimized by computer molecular modeling. Using Comparative Molecular Field Analysis (CoMFA), a computer model was generated from the minimized metallocene structures and actual polymerization performance. When the model was tested, a statistically valid correlation of the model's predicted DSC melting point with the observed DSC melting point was found. The model indicates the extent of the steric effect of these alkyl substituents and their influence on the DSC melting point. 相似文献