Reviews & Analysis

Verification efforts of density-functional theory (DFT) calculations are of crucial importance to evaluate the reliability of simulation results. In this Expert Recommendation, we suggest metrics for DFT verification, illustrating them with an all-electron reference dataset of 960 equations of state covering the whole periodic table (hydrogen to curium) and discuss the importance of improving pseudopotential codes.

This Expert Recommendation describes how high conversion efficiency in high-order harmonic generation can be achieved over a large range of pressures and medium lengths, following a hyperbolic equation, and provides design guidance for future high-flux extreme ultraviolet sources.

A key challenge in fabricating devices out of 2D materials is in making good electrical contact. This Expert Recommendation discusses the physics of electrical contacts and provides tips on improving contact quality.

This Expert Recommendation provides a guide to identifying practical situations where the likelihood ratio test statistic cannot be approximated by a χ² distribution and proposes adequate solutions.

Random lasing, which exploits disorder to enhance stimulated emission, challenges the conventional descriptions of lasing. This Expert Recommendation describes experimental methods required to properly assess and demonstrate random lasing action.

A group of experts suggests ways in which deep learning can be used to enhance the potential for discovery in multi-messenger astrophysics.