We present a study combining magnetization measurements and direct magneto-optical flux imaging on Nb films, which contain periodic arrays of nanoholes and have been grown on anodized aluminum oxide (AAO) substrates. The magnetization measurements reveal pronounced matching effects in the critical current over the entire temperature range from 4.2 K to Tc. The flux images do not reveal signatur...

By a hyperbolic 3-manifold we mean a complete orientable hyperbolic 3-manifold of finite volume, that is a quotient H/Γ with Γ ⊂ PSL2C a discrete subgroup of finite covolume (here briefly “a Kleinian group”). Among hyperbolic 3-manifolds, the arithmetic ones form an interesting, and in many ways more tractable, subclass. The tractability comes from the availability of arithmetic tools and invar...

The quantum anomalous Hall (QAH) effect is sometimes observed in twisted bilayer graphene (tBG) when it nearly aligned with an encapsulating hexagonal boron nitride (hBN) layer. We propose that the appearance or absence of QAH individual devices could be related to commensurability between graphene/graphene and graphene/hBN moir\'e patterns. identify a series points $(\theta_{\rm GG},\theta_{\r...