Recent measurements of charge-dependent azimuthal correlations in high-energy heavy-ion collisions have indicated charge-separation signals perpendicular to the reaction plane, and have been related to the chiral magnetic effect (CME). However, the correlation signal is contaminated with the background caused by the collective motion (flow) of the collision system, and an effective approach is needed to remove the flow background from the correlation. We present a method study with simplified Monte Carlo simulations and a multi-phase transport model, and develop a scheme to reveal the true CME signal via the event-shape engineering with the flow vector of the particles of interest.

Under the influence of the next-nearest-neighbor interaction, we theoretically investigate the occurrence of Bloch oscillations in zigzag waveguide arrays. Because of the special topological configuration of the lattice itself, the second-order coupling (SOC) can be enhanced significantly and leads to the band alteration beyond the nearest-neighbor model, i.e., the offset of minimum value from the band edge. Contrary to the behavior in the vanishing SOC, the oscillation patterns exhibit new features, namely, a double turning-back occurs when the beam approaches the band edge. Our results can be applied to some ordered-lattice systems.

This study proposes a highly sensitive sensor based on localised spoof surface plasmons (LSSPs) for omni‐directional cracks inspection in metal surfaces. A defected ground structure based on the complementary metallic spiral structure (CMSS) is embedded on the ground of a microstrip line to excite LSSPs, and the mode characteristics of these LSSPs are studied. Then an equivalent lumped circuit method is presented to reveal the operation mechanisms behind the trapped LSSPs. Due to the strong field confinement, LSSPs are used as a sensor to inspect cracks in a metal surface, where a 0.2‐mm‐wide and 2‐mm‐deep crack yields a 400 MHz resonance frequency shift. Meanwhile, a big resonance frequency shift is also obtained for omni‐directional detection of surface cracks because of the rotational symmetry of the CMSS. It indicates that the proposed sensor is orientation independent, so that any cracks would not be missed in the testing and cracks would be located more easily. Therefore, the proposed sensor has more potentials than other sensors in actual practice.

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