We carried out a wavelength-dependent homodyne and heterodyne transient grating ͑TG͒ studies on a resonant system, rhodamine 640 in dimethylsulfoxide, with a simplified diffractive optics method. The real and imaginary components of the third-order molecular polarization at different excitation wavelengths have a similar longtime decay ͑Ͼ200 fs͒, while the amplitude of the real component is strongl...

The approximation of a nonresonant orbit with a sequence of resonant orbits is considered for the holomorphic maps of the complex plane. The problem is motivated by hamiltonian dynamics (Greene's conjecture) and we consider a complexiied hamiltonian map in the region (far from the section of real dynamics) where it can be reduced to an holomorphic map of a single complex variable. For a sequenc...

We have successfully determined the hitherto unknown sign of the B(4)(4) Stevens crystal-field parameter of the tetragonal heavy-fermion compound CeCu(2)Si(2) using vector q-dependent nonresonant inelastic x-ray scattering experiments at the cerium N(4,5) edge. The observed difference between the two different directions, q∥[100] and q∥[110], is due to the anisotropy of the crystal-field ground...

A major impediment to the use of coherent anti-Stokes Raman scattering (CARS) to identify biological molecules is that the illumination levels required to produce a measurable signal often also produce significant nonresonant background from the medium, especially from water. We present a method of nonlinear interferometry to differentiate between which components of the anti-Stokes signal are ...

We highlight the importance of carrier-phonon coupling in inorganic lead halide perovskite nanocrystals. The low-temperature photoluminescence (PL) spectrum of CsPbBr3 has been investigated under a nonresonant and a nonstandard, quasi-resonant excitation scheme, and phonon replicas of the main PL band have been identified as due to the Fröhlich interaction. The energy of longitudinal optical (L...

Future ultrafast x-ray light sources might image ultrafast coherent electron motion in real space and in real time. For a rigorous understanding of such an imaging experiment, we extend the theory of nonresonant x-ray scattering to the time domain. The role of energy resolution of the scattering detector is investigated in detail. We show that time-resolved nonresonant x-ray scattering with no ...

A femtosecond degenerate four-wave mixing (fs-DFWM) technique for probing the alignment of molecules is described. The rotational wave packet generated by a strong pump beam modulates the nonresonant third-order susceptibility of the gas and this modulation is observed using a noncollinear background-free setup. As a demonstration of the technique, we measure the alignment of a linear molecule ...

We present a novel, hand-held microscope probe for acquiring confocal images of biological tissue. This probe generates images by scanning a fiber-lens combination with a miniature electromagnetic actuator, which allows it to be operated in resonant and nonresonant scanning modes. In the resonant scanning mode, a circular field of view with a diameter of 190 μm and an angular frequency of 127 H...

The response to the field sequence of nonresonant hole burning, a pump-wait-probe experiment originally designed to investigate slow relaxation in complex systems, is calculated for a model of Brownian oscillators, thus including inertial effects. In the overdamped regime the model predictions are very similar to those of the purely dissipative stochastic models investigated earlier, including ...

The partial widths of the decays D s → φπ and D s → πππ-nonresonant are computed within the effective quark model with chiral symmetry involving Heavy quark effective theory (HQET) and Chiral perturbation theory at the quark level (CHPT)q with linear realization of chiral U(3) × U(3) symmetry. It is shown that for the explanation of the experimental probability of the D s → πππ– nonresonant dec...