{"id":3869,"date":"2022-02-15T17:32:00","date_gmt":"2022-02-15T08:32:00","guid":{"rendered":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/?p=3869"},"modified":"2022-11-15T17:35:41","modified_gmt":"2022-11-15T08:35:41","slug":"antiferromagnetic-excitonic-insulator-state-in-sr3ir2o7","status":"publish","type":"post","link":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/news\/3869\/","title":{"rendered":"Antiferromagnetic excitonic insulator state in Sr3Ir2O7"},"content":{"rendered":"\n<div class=\"wp-block-image\"><figure class=\"alignright size-large is-resized\"><a href=\"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-content\/uploads\/sites\/2\/2022\/11\/795316b92fc766b0181f6fef074f03fa.jpg\"><img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-content\/uploads\/sites\/2\/2022\/11\/795316b92fc766b0181f6fef074f03fa-1024x573.jpg\" alt=\"\" class=\"wp-image-3870\" width=\"512\" height=\"287\" srcset=\"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-content\/uploads\/sites\/2\/2022\/11\/795316b92fc766b0181f6fef074f03fa-1024x573.jpg 1024w, https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-content\/uploads\/sites\/2\/2022\/11\/795316b92fc766b0181f6fef074f03fa-300x168.jpg 300w, https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-content\/uploads\/sites\/2\/2022\/11\/795316b92fc766b0181f6fef074f03fa.jpg 1294w\" sizes=\"(max-width: 512px) 100vw, 512px\" \/><\/a><\/figure><\/div>\n\n\n\n<p>Excitonic insulators are usually considered to form via the condensation of a soft charge mode of bound electron-hole pairs. This, however, presumes that the soft exciton is of spin-singlet character. Early theoretical considerations have also predicted a very distinct scenario, in which the condensation of magnetic excitons results in an antiferromagnetic excitonic insulator state. Here we report resonant inelastic x-ray scattering (RIXS) measurements of Sr<sub>3<\/sub>Ir<sub>2<\/sub>O<sub>7<\/sub>. By isolating the longitudinal component of the spectra, we identify a magnetic mode that is well-defined at the magnetic and structural Brillouin zone centers, but which merges with the electronic continuum in between these high symmetry points and which decays upon heating concurrent with a decrease in the material\u2019s resistivity. We show that a bilayer Hubbard model, in which electron-hole pairs are bound by exchange interactions, consistently explains all the electronic and magnetic properties of Sr<sub>3<\/sub>Ir<sub>2<\/sub>O<sub>7<\/sub>&nbsp;indicating that this material is a realization of the long-predicted antiferromagnetic excitonic insulator phase.<\/p>\n\n\n\n<p>See below for more information.<\/p>\n\n\n\n<ul><li>Aritcle URL :\u00a0<a href=\"https:\/\/www.nature.com\/articles\/s41467-022-28207-w\">https:\/\/www.nature.com\/articles\/s41467-022-28207-w<\/a><\/li><\/ul>\n","protected":false},"excerpt":{"rendered":"Excitonic insulators are usually considered to form via the condensation of a soft charge mode of bound electr [&hellip;]","protected":false},"author":7,"featured_media":3870,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[3],"tags":[36],"_links":{"self":[{"href":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/posts\/3869"}],"collection":[{"href":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/comments?post=3869"}],"version-history":[{"count":2,"href":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/posts\/3869\/revisions"}],"predecessor-version":[{"id":3873,"href":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/posts\/3869\/revisions\/3873"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/media\/3870"}],"wp:attachment":[{"href":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/media?parent=3869"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/categories?post=3869"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.phys.s.u-tokyo.ac.jp\/en\/wp-json\/wp\/v2\/tags?post=3869"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}