{"id":4846,"date":"2021-08-23T12:29:00","date_gmt":"2021-08-23T11:29:00","guid":{"rendered":"https:\/\/research.kent.ac.uk\/pqm\/?p=4846"},"modified":"2021-08-23T20:24:39","modified_gmt":"2021-08-23T19:24:39","slug":"time-reversal-symmetry-breaking-in-superconductors-through-loop-supercurrent-order","status":"publish","type":"post","link":"https:\/\/research.kent.ac.uk\/pqm\/2021\/08\/23\/time-reversal-symmetry-breaking-in-superconductors-through-loop-supercurrent-order\/","title":{"rendered":"Time-reversal symmetry breaking in superconductors through loop supercurrent order"},"content":{"rendered":"<p>Our paper on loop supercurrent order has been published in the open-access New Journal Physics. In it we propose a new way superconductors can break time-reversal symmetry spontaneously which works even if the electron pairing is singlet, on-site, intra-orbital and without breaking the lattice translation symmetry. The trick is to condensed the Cooper pairs with a different phase of the order parameter on different sites within the unit cell. This leads to Josephson currents which generate magnetic fields whose size is compatible with what is observed experimentally in some real materials. <a href=\"https:\/\/doi.org\/10.1088\/1367-2630\/ac17ba\">Follow the link below<\/a> to read the full text of our paper:<\/p>\n<h3 class=\"wd-jnl-art-title\">Time-reversal symmetry breaking in superconductors through loop supercurrent order<\/h3>\n<p class=\"mb-0\"><span data-authors=\"\"> <span class=\"nowrap\">Sudeep Kumar Ghosh<\/span><\/span><span data-authors=\"\">, <span class=\"nowrap\">James F Annett<\/span> and <span class=\"nowrap\">Jorge Quintanilla<\/span><\/span><\/p>\n<p class=\"mb-0\"><em>New J. Phys.<\/em> <strong>23<\/strong>, 083018 (2021)<\/p>\n<p><a href=\"https:\/\/doi.org\/10.1088\/1367-2630\/ac17ba\">https:\/\/doi.org\/10.1088\/1367-2630\/ac17ba<\/a><\/p>\n<h4 id=\"artAbst\" class=\"collapse-blocked\">Abstract<\/h4>\n<div class=\"article-text wd-jnl-art-abstract cf\">\n<p>We propose a novel superconducting ground state where microscopic supercurrent loops form spontaneously within a unit cell at the superconducting transition temperature with only uniform, onsite and intra-orbital singlet pairing. As a result of the circulating currents time-reversal symmetry (TRS) is spontaneously broken in the superconducting state. Using Ginzburg\u2013Landau theory we describe in detail how these currents emerge in a toy model. We discuss the crystallographic symmetry requirements more generally to realize such a state and show that they are met by the Re<sub>6<\/sub><i>X<\/i> (<i>X<\/i> = Zr, Hf, Ti) family of TRS-breaking, but otherwise seemingly conventional, superconductors. We estimate an upper bound for the resulting internal magnetic fields and find it to be consistent with recent muon-spin relaxation experiments.<\/p>\n<p>arXiv trackback URL: <a href=\"https:\/\/arxiv.org\/trackback\/1803.02618\">https:\/\/arxiv.org\/trackback\/1803.02618<\/a><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Our paper on loop supercurrent order has been published in the open-access New Journal Physics. In it we propose a new way superconductors can break time-reversal symmetry spontaneously which works even if the electron pairing is singlet, on-site, intra-orbital and without breaking the lattice translation symmetry. The trick is to condensed the Cooper pairs with [&hellip;]<\/p>\n","protected":false},"author":134,"featured_media":4849,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[568],"tags":[584,819,988,985,628,816,966,972,553,587,813],"class_list":["post-4846","post","type-post","status-publish","format-standard","hentry","category-publications","tag-condensed-matter-physics","tag-group-theory","tag-loop-supercurrents","tag-lsc","tag-magnetism","tag-muon-spin-relaxation","tag-musr","tag-superconductivity","tag-superconductors","tag-theory","tag-time-reversal-symmetry-breaking"],"acf":[],"_links":{"self":[{"href":"https:\/\/research.kent.ac.uk\/pqm\/wp-json\/wp\/v2\/posts\/4846","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/research.kent.ac.uk\/pqm\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/research.kent.ac.uk\/pqm\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/research.kent.ac.uk\/pqm\/wp-json\/wp\/v2\/users\/134"}],"replies":[{"embeddable":true,"href":"https:\/\/research.kent.ac.uk\/pqm\/wp-json\/wp\/v2\/comments?post=4846"}],"version-history":[{"count":2,"href":"https:\/\/research.kent.ac.uk\/pqm\/wp-json\/wp\/v2\/posts\/4846\/revisions"}],"predecessor-version":[{"id":4855,"href":"https:\/\/research.kent.ac.uk\/pqm\/wp-json\/wp\/v2\/posts\/4846\/revisions\/4855"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/research.kent.ac.uk\/pqm\/wp-json\/wp\/v2\/media\/4849"}],"wp:attachment":[{"href":"https:\/\/research.kent.ac.uk\/pqm\/wp-json\/wp\/v2\/media?parent=4846"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/research.kent.ac.uk\/pqm\/wp-json\/wp\/v2\/categories?post=4846"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/research.kent.ac.uk\/pqm\/wp-json\/wp\/v2\/tags?post=4846"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}