Twist-Dependent Tuning of Excitonic Emissions in Bilayer WSe.

Monolayer (ML) transition metal dichalcogenides (TMDCs) have been rigorously studied to comprehend their rich spin and valley physics, exceptional optical properties, and ability to open new avenues in fundamental research and technology. However, intricate analysis of twisted homobilayer (t-BL) systems is highly required due to the intriguing twist angle (t-angle)-dependent interlayer effects on optical and electrical properties. Here, we report the evolution of the interlayer effect on artificially stacked BL WSe, grown using chemical vapor deposition (CVD), with t-angle in the range of 0 ≤ θ ≤ 60°.

Probing CP violation with the electric dipole moment of atomic mercury.

The electric dipole moment of atomic 199Hg induced by the nuclear Schiff moment and the tensor-pseudotensor electron-nucleus interactions are calculated. For this, we develop and employ a novel method based on the relativistic coupled-cluster theory. The results of our theoretical calculations, combined with the latest experimental result of the 199Hg electric dipole moment, provide new bounds on the T reversal or CP violation parameters thetaQCD, the tensor-pseudotensor coupling constant CT, and (tilde d(u)-tilde d(d)).

Electric quadrupole moments of the D states of alkaline-earth-metal ions.

The electric quadrupole moment for the 4d(2)D(5/2) state of (88)Sr(+); one of the most important candidates for an optical clock, has been calculated using the relativistic coupled-cluster theory. This is the first application of this theory to determine atomic electric quadrupole moments. The result of the calculation is presented and the important many-body contributions are highlighted.