Weyl points are the crossings of linearly dispersing energy bands of three-dimensional crystals, providing the opportunity to explore a variety of intriguing phenomena such as topologically protected surface states and chiral anomalies. However, the lack of an ideal Weyl system in which the Weyl points all exist at the same energy and are separated from any other bands poses a serious limitation to the further development of Weyl physics and potential applications. By experimentally characterizing a microwave photonic crystal of saddle-shaped metallic coils, we observed ideal Weyl points that are related to each other through symmetry operations. Topological surface states exhibiting helicoidal structure have also been demonstrated. Our system provides a photonic platform for exploring ideal Weyl systems and developing possible topological devices.

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Spin-orbit coupling has proven indispensable in the realization of topological materials and, more recently, Ising pairing in two-dimensional superconductors. This pairing mechanism relies on inversion symmetry–breaking and sustains anomalously large in-plane polarizing magnetic fields whose upper limit is predicted to diverge at low temperatures. Here, we show that the recently discovered superconductor few-layer stanene, epitaxially strained gray tin (α-Sn), exhibits a distinct type of Ising pairing between carriers residing in bands with different orbital indices near the Γ-point. The bands are split as a result of spin-orbit locking without the participation of inversion symmetry–breaking. The in-plane upper critical field is strongly enhanced at ultralow temperature and reveals the predicted upturn.

Nowadays, a considerable progress in the syngas-to-olefins (STO) reaction has been made by physically mixed oxide-zeolite catalysts; however, contradictions concerning the reaction mechanism still exist. Although complete separation of the mixed catalysts should help to understand the STO reaction, it can result in lower CO conversion and selectivity of light olefins. Here, we report a stable and selective dual-bed STO catalyst ZnAlO x /SAPO-34, which contains a SAPO-34 molecular sieve packed below ZnAlO x oxide. C2–4 olefins in hydrocarbons can reach 77.0% with only 33.1% CO2 selectivity at 663 K. No significant deactivation is observed during a 100 h test. ZnAlO x itself can be used as a catalyst for the syngas-to-dimethyl ether (STD) reaction. Because the dual-bed catalyst presents similar reaction results and “hydrocarbon pool” intermediates to the mixed one, the STO reaction over a mixed catalyst can be understood as the combination of STD and MTO reactions regardless of catalytic behaviors and mechanisms.