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The stacking order and twist angle provide abundant opportunities for engineering band structures of two-dimensional materials, including the formation of moire bands, flat bands, and topologically nontrivial bands. The inversion symmetry breaking in rhombohedral-stacked transitional metal dichalcogenides (TMDCs) endows them with an interfacial ferroelectricity associated with an out-of-plane electric polarization. By utilizing twist angle as a knob to construct rhombohedral-stacked TMDCs, antiferroelectric domain networks with alternating out-of-plane polarization can be generated. Here, we demonstrate that such spatially periodic ferroelectric polarizations in parallel-stacked twisted WSe2 can imprint their moire potential onto a remote bilayer graphene. This remote moire potential gives rise to pronounced satellite resistance peaks besides the charge-neutrality point in graphene, which are tunable by the twist angle of WSe2. Our observations of ferroelectric hysteresis at finite displacement fields suggest the moire is delivered by a long-range electrostatic potential. The constructed superlattices by moire ferroelectricity represent a highly flexible approach, as they involve the separation of the moire construction layer from the electronic transport layer. This remote moire is identified as a weak potential and can coexist with conventional moire. Our results offer a comprehensive strategy for engineering band structures and properties of two-dimensional materials by utilizing moire ferroelectricity.

In this report, we use data from China's 2010 census to examine China's urbanization and migration patterns from an international perspective. First, we present an overview of the historical use of the city as a means for control and administration across Chinese history. Second, we examine the comparability and reliability of official demographic data and find that definitions of urbanization change dramatically across China's official censuses. Delving into the contours of urbanization and internal migration during the post-Mao era, we find that, even within the constraints of the hukou system, China truly has a national labor market and that a large portion of the working-age population in cities is made up of migrant labor. Despite the rise of populous and densely populated cities in China, a look at China's urbanization in an international perspective suggests that China is under-urbanized. Subsequently, we examine what China's human resource profile in urban and rural areas portends for its ongoing urbanization drive. Finally, we offer some concluding observations on how modern technological advances may affect migration and urbanization in China., Contents Executive Summary 1 I. Introduction 3 II. Background 6 III. Data on Population and Urbanization in Contemporary China: 9 Availability and Reliability IV. The Geography and Demography of Migration [...]