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A new spin on C60: Axially chiral, pushpull buta-1,3-diene chromophores conjugated to vicinally methylated fullerenes (see picture) have high barriers of rotation about their chiral axes. These high barriers allowed their optical resolution and the determi ...
New enantiomerically pure alleno-acetylenic macrocycles were prepd. by oxidative homocoupling of optically active 1,3-diethynylallenes. Enantiomer sepn. resulted from a combined strategy of synthesis and chiral HPLC techniques. Two other achiral stereoisom ...
By performing pump-probe experiments, we study the relaxation dynamics of spin-polarized excitons in a wurtzite GaN/AlGaN quantum well (QW)grown by metal organic vapor phase epitaxy. The circular degree of polarization of the differential reflectivity sign ...
Many ferroelectric solid solutions exhibit enhanced electromechanical properties at the morphotropic boundary separating two phases with different orientations of polarization. The mechanism of properties enhancement is associated with easy paths for polar ...
Electromagnetically induced transparency is a quantum interference effect observed in atoms and molecules, in which the optical response of an atomic medium is controlled by an electromagnetic field. We demonstrated a form of induced transparency enabled b ...
Using a multi-heterodyne scanning near-field optical microscope, we detect two arbitrary, orthogonal components of the near field. A numerical treatment of the experimental data allows the retrieval of the transverse and longitudinal components of the mode ...
A reflecting cell allowing the dynamic and independent control of the reflection phase of two perpendicular linearly-polarized waves is presented. This capability is useful for the implementation of dual-polarized beam-reconfigurable reflectarrays, as well ...
Institute of Electrical and Electronics Engineers2010
In this work we study from a theoretical point of view microcavities embedding organic materials featuring vibronic progressions. As already shown in seminal experiments, the presence of vibronic replicas largely enriches the physics of such systems with t ...
The mechanism of chiral induction in an optically pure 1,3-diethynylallene, from the central chiral allene moiety into directly adjacent TCBD chromophores, was confirmed and clarified. Only one low-energy conformer is found in calcns. of the potential ener ...
This review discusses recent advances in understanding origins of large piezoelectric properties in some ferroelectric materials. In particular, it addresses the role of polarization rotation and monoclinic phases. It is suggested that the polarization rot ...