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The fluorescence lifetime of living tissues is, in certain cases, related to their pathol. state and is therefore of interest for cancer detection. Measuring fluorescence lifetime in vivo during an endoscopic examn. has thus been a challenging objective fo ...
The ab-plane optical reflectance of single crystal of Bi2Sr2Ca(Cu1-xNix)(2)O8+d, for x = 0.0215, has been measured from 80 to 40 000 cm(-l) (10 meV-5 eV) and at temperatures between 20 and 300 K. Through Ni substitution, the optical conductivity shows a br ...
A new scheme is proposed for solid-state NMR which uses simultaneous frequency and amplitude modulation (SFAM) to restore heteronuclear dipolar interactions between two unlike spin-1/2 nuclei such as 13C and 15N under fast magic angle spinning (MAS). The c ...
Two novel schemes are described for cross polarization in NMR that make it possible to achieve an efficient transfer of polarization from abundant I spins to dil. S spins under high-speed magic angle spinning spectroscopy, which is useful for systems with ...
Photoluminescence lifetimes of the n = 2 level in a large quantum well show a clear nonmonotonic dependence on the density of optically generated carriers. Varying the power density over five orders of magnitude we prove directly the high efficiency of car ...
We performed Monte Carlo simulation of electron response to a strong pumping wave (443 GHz) and weak signal harmonic waves (886 and 1329 GHz) in silicon. A negative dynamic conductivity is found to arise for 1329 GHz above a threshold value of the pumping ...
Two all-fiber wavelength tunable devices, one utilizing thermal tuning and a second based on strain tuning, have been produced by combining resistive Ti/Pt and piezoelectric ZnO fiber coatings with fiber Bragg gratings (FBGs). The Ti and Pt coatings with t ...
To excite and refocus single quantum coherences in a three-level system with a quadrupolar interaction, it is possible to use frequency-modulated pulses with two diverging frequency components that are swept simultaneously through the two single-quantum tr ...
A new method is presented for decoupling spins with S = 1 like D in anisotropic media while observing other spins such as residual protons in partly deuterated samples. The carrier frequency of a weak radiofrequency (RF) field is applied near the center of ...
For a rapid determination of saturation factors in surface coil NMR spectroscopy, the recently published (90 degrees-tau-180 degrees-tau-90 degrees-tau-) SUFIR sequence was modified with adiabatic pulse cycles. Signals were acquired after each of the two 9 ...
