Longying Wen

Near 1310 nm photonic-crystal surface-emitting lasers (PCSELs) are attractive narrow-beam sources for optical communication and sensing, but their final design refinement is costly. Small geometry changes simultaneously shift the band-edge resonance, cavity leakage, far-field divergence, and the numerical stability of a high-$Q$ decay fit, while every full-wave trial requires a time-domain simulation.

The northern arid belt The northern arid belt is an east–west oriented arid zone between 35 and 45° N from western China to the Pacific coast with an annual rainfall of less than 500 mm (Figure 1). It first developed in early Tertiary, reduced in the Miocene, re-developed in the Pliocene and reduced but persisted in the Quaternary to today (Bai et al., 2016; Guo et al., 2008; Tiffney & Manchester, 2001).