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Localization and delocalization of light in photonic moire lattices 期刊论文
NATURE, 2020, 577 (7788) : 42-+
作者:  Wang, Peng;  Zheng, Yuanlin;  Chen, Xianfeng;  Huang, Changming;  Kartashov, Yaroslav V.;  Torner, Lluis;  Konotop, Vladimir V.;  Ye, Fangwei
收藏  |  浏览/下载:12/0  |  提交时间:2020/07/03

Moire lattices consist of two superimposed identical periodic structures with a relative rotation angle. Moire lattices have several applications in everyday life, including artistic design, the textile industry, architecture, image processing, metrology and interferometry. For scientific studies, they have been produced using coupled graphene-hexagonal boron nitride monolayers(1,2), graphene-graphene layers(3,4) and graphene quasicrystals on a silicon carbide surface(5). The recent surge of interest in moire lattices arises from the possibility of exploring many salient physical phenomena in such systems  examples include commensurable-incommensurable transitions and topological defects(2), the emergence of insulating states owing to band flattening(3,6), unconventional superconductivity(4) controlled by the rotation angle(7,8), the quantum Hall effect(9), the realization of non-Abelian gauge potentials(10) and the appearance of quasicrystals at special rotation angles(11). A fundamental question that remains unexplored concerns the evolution of waves in the potentials defined by moire lattices. Here we experimentally create two-dimensional photonic moire lattices, which-unlike their material counterparts-have readily controllable parameters and symmetry, allowing us to explore transitions between structures with fundamentally different geometries (periodic, general aperiodic and quasicrystal). We observe localization of light in deterministic linear lattices that is based on flatband physics(6), in contrast to previous schemes based on light diffusion in optical quasicrystals(12), where disorder is required(13) for the onset of Anderson localization(14) (that is, wave localization in random media). Using commensurable and incommensurable moire patterns, we experimentally demonstrate the twodimensional localization-delocalization transition of light. Moire lattices may feature an almost arbitrary geometry that is consistent with the crystallographic symmetry groups of the sublattices, and therefore afford a powerful tool for controlling the properties of light patterns and exploring the physics of periodic-aperiodic phase transitions and two-dimensional wavepacket phenomena relevant to several areas of science, including optics, acoustics, condensed matter and atomic physics.


  
Experiences of Urban Militarism: Spatial Stigma, Ruins and Everyday Life 期刊论文
INTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, 2019, 43 (5) : 848-869
作者:  Pasquetti, Silvia
收藏  |  浏览/下载:5/0  |  提交时间:2019/11/27
everyday life  Palestinians in urban Israel  ruination  spatial stigma  urban marginality  urban militarism  Lydda-Lod  Israel  
Irregular Connections: Everyday Energy Politics in Catalonia 期刊论文
INTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, 2019, 43 (2) : 337-353
作者:  Angel, James
收藏  |  浏览/下载:7/0  |  提交时间:2019/04/09
Energy  infrastructure  social reproduction  everyday life  urban social movements  Catalonia  Barcelona  
Problem Spaces' and Struggles Over the Right to the City: Challenges of Living Differentially in a Gentrifying Istanbul Neighborhood 期刊论文
INTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, 2018, 42 (6) : 1030-1047
作者:  Oz, Ozlem;  Eder, Mine
收藏  |  浏览/下载:7/0  |  提交时间:2019/04/09
urban transformation  contested space  everyday life  right to the city  gentrification  Istanbul  Turkey  
Socio-technical transitions and dynamics in everyday consumption practice 期刊论文
GLOBAL ENVIRONMENTAL CHANGE-HUMAN AND POLICY DIMENSIONS, 2018, 52: 1-9
作者:  Greene, Mary
收藏  |  浏览/下载:0/0  |  提交时间:2019/04/09
Sustainable consumption  Energy  Socio-technical transitions  Domestic  Social practice  Everyday life  Biography  
Urban Distinctions: Class, Culture and Sociability in the City of Porto 期刊论文
INTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, 2018, 42 (1) : 126-137
作者:  Pereira, Virgilio Borges
收藏  |  浏览/下载:0/0  |  提交时间:2019/04/09
class  culture  everyday life  local space  urban inequality  Bourdieu  Portugal