{"id":966,"date":"2013-09-20T17:46:26","date_gmt":"2013-09-20T15:46:26","guid":{"rendered":"https:\/\/webs.uab.cat\/giq\/seminar\/edge-states-and-efficient-transport-2-dimensional-quantum-walk\/"},"modified":"2013-09-20T17:46:26","modified_gmt":"2013-09-20T15:46:26","slug":"edge-states-and-efficient-transport-2-dimensional-quantum-walk","status":"publish","type":"seminar","link":"https:\/\/webs.uab.cat\/giq\/seminar\/edge-states-and-efficient-transport-2-dimensional-quantum-walk\/","title":{"rendered":"Edge states and efficient transport in a 2-dimensional Quantum Walk"},"content":{"rendered":"<p>Consider a discrete time quantum walk on a 2-dimensional square lattice, with particles starting from point A and detected at point B. To establish an efficient&nbsp; channel for transport from A to B, which links (edges) in the lattice should you remove? We show that the counterintuitive strategy of picking a path that connects A and B, and removing links that cross this path, can create such a channel, that uses topologically protected edge states [1]. The existence of these edge states depends on the bulk properties of the quantum walk (including topological invariants other than the Chern number [2]), and on the way the links are removed (similarly to 1D quantum walks [3]), but not on the precise shape of the path. The channel ensures a transmission probability independent of the distance of A and B, even in the presence of static disorder, which induces Anderson localization. Time-dependent disorder, however, causes decoherence and thus makes the channel lossy.<\/p>\n<p>References<br \/>[1] T. Kitagawa, Quant. Inf. Proc. 1570-0755 (2012); arXiv:1112.1882<br \/>[2] M. S. Rudner, N. H. Lindner, E. Berg, M. Levinot, arXiv:1212.3324 (2012)<br \/>[3] J. K. <span class=\"il\">Asboth<\/span>, Phys. Rev. B 86, 195414 (2012)<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Consider a discrete time quantum walk on a 2-dimensional square lattice, with particles starting from point A and detected at point B. To establish an efficient&nbsp; channel for transport from A to B, which links (edges) in the lattice should you remove? We show that the counterintuitive strategy of picking a path that connects A [&hellip;]<\/p>\n","protected":false},"author":20,"featured_media":0,"template":"","class_list":["post-966","seminar","type-seminar","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/webs.uab.cat\/giq\/wp-json\/wp\/v2\/seminar\/966","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/webs.uab.cat\/giq\/wp-json\/wp\/v2\/seminar"}],"about":[{"href":"https:\/\/webs.uab.cat\/giq\/wp-json\/wp\/v2\/types\/seminar"}],"author":[{"embeddable":true,"href":"https:\/\/webs.uab.cat\/giq\/wp-json\/wp\/v2\/users\/20"}],"wp:attachment":[{"href":"https:\/\/webs.uab.cat\/giq\/wp-json\/wp\/v2\/media?parent=966"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}