Nuclear SpinDependent Effects of Parity Nonconservation in OrthoH2 We report a theoretical treatment of the nuclear spindependent spatial parity nonconserving (NSDPNC) electronxe2x80x93nuclear interaction effect in the diatomic homonuclear orthoH     2     molecule. The magnetic dipole transition between     v  1     and     v  0     vibrational sublevels of the ground       1   xcexa3 g       state is examined. The orthohydrogen molecule is a unique molecular system where the parity nonconserving (PNC) nuclear spindependent interaction due to the neutral weak currents can be directly observed and the corresponding coupling constant can be extracted from the future experiments. The theoretical simulation shows that using the cavityenhanced scheme in conjunction with the record achievement of the intracavity absorption spectroscopy, the experiment on the observation of the NSDPNC effect due to the neutral weak current in orthoH     2     looks feasible.

Interaction and Entanglement of a Pair of Quantum Emitters near a Nanoparticle: Analysis beyond ElectricDipole Approximation In this paper, we study the collective effects which appear as a pair of quantum emitters is positioned in close vicinity to a plasmonic nanoparticle. These effects include multipolexe2x80x93multipole interaction and collective decay, the strengths and rates of which are modified by the presence of the nanoparticle. As a result, entanglement is generated between the quantum emitters, which survives in the stationary state. To evaluate these effects, we exploit the Greenxe2x80x99s tensorbased quantization scheme in the Markovian limit, taking into account the corrections from lightxe2x80x93matter coupling channels higher than the electric dipole. We find these higherorder channels to significantly influence the collective rates and degree of entanglement, and in particular, to qualitatively influence their spatial profiles. Our findings indicate that, apart from quantitatively modifying the results, the higherorder interaction channels may introduce asymmetry into the spatial distribution of the collective response.