Starting from an effective Skyrme interaction we present a method to take into account the coupling between oneand two-phonon terms in the wave functions of excited states. The approach is a development of a finite rank separable approximation for the quasiparticle RPA calculations proposed in our previous work. The influence of the phonon-phonon coupling on energies and transition probabilitie...

The magnetic structure of the localized-5f uranium intermetallic compound U3Pd20Si6 has been determined by means of a neutron diffraction experiment. Our data demonstrate that this compound has a collinear coupling of the sublattice ordering of the uranium spins on the 4a and 8c sites. We conclude that higher-order exchange and/or quadrupole interactions are necessary to stabilize this unique c...

Crystals of plasmonic metal nanoparticles have intriguing optical properties. They reach the regimes ultrastrong and deep strong light-matter coupling, where photonic states need to be included in simulation material We propose a quantum description plasmon polaritons supercrystals that starts from dipole quadrupole excitations nanoparticle building blocks their coupling photons. Our model exce...

Simulations of solid-state Si N M R spectra in nitrogen-containing silicon ceramics and glasses are described. The range of SiN ; t04 ._x tetrahedra is covered, with emphasis on the experimental conditions needed to observe the effect of the incompletely averaged Si, 1 4 N dipolar coupling. A simple equation is discussed concerning its use in the interpretation of these Si spectra, including th...

Combining near-field measurements with coupled-mode-theory analyses, we unambiguously identify all resonant modes in coupled systems containing two photonic resonators. Based on this technique, we perform extensive microwave experiments to study how the inter-resonator coupling varies against various configurational parameters. Our experimental results quantitatively verify a previously establi...

Seventyseven a-type rotational transitions of Orthofluorobenzonitrile were observed and assigned in the 8 — 25 GHz frequency range. The spectrum was recorded using the high resolution microwave Fourier transform spectrometer constructed at Kiel University. For most transitions the l4N quadrupole hfs patterns could be fully resolved. The spectroscopic constants obtained by a fit to the observed ...

We measured the nondipole parameters for the spin-orbit doublets Xe 4d5/2 and Xe 4d3/2 over a photon-energy range from 100 eV to 250 eV at beamline 8.0.1.3 of the Advanced Light Source at the Lawrence Berkeley National Laboratory. Significant nondipole effects are found at relatively low energies as a result of Cooper minima in dipole channels and interchannel coupling in quadrupole channels. M...

Static quadrupole moments (0) of 8+ isomers in 88 90Zr and the 2' + isomer in 9'Zr, as well as 0 ratios of 8+ isomers in Mo, have been measured with the time-differential perturbedangular-distribution technique. The isomers were excited by pulsed heavy-ion beams and recoil implanted into single crystals of Zr in which their quadrupole precession was observed. Our results, the first such data fo...

The nuclear magnetic resonance of Zn in hexagonal close-packed Zn metal has been observed at 4.2 K by pulsed NMR with three different frequencies. The spin echo profile showed a well resolved powder pattern due to electric quadrupole interaction. The quadrupole coupling constant was determined to be e q Q/h = 12.0 (4) MHz. The spinspin and spin-lattice-relaxation times were measured to be T2 = ...

We consider a hydrogenic system with a nucleus of finite mass. The coupling of the radiation field to the center of mass motion gives rise to an effective scalar type coupling. This induced scalar photon interaction emerges as a correction in competition with the usual multipole interactions. This effect is particularly important in positronium where the electric quadrupole interaction is total...