{"id":164,"date":"2016-04-21T21:00:41","date_gmt":"2016-04-21T21:00:41","guid":{"rendered":"http:\/\/cgisvr.physics.rutgers.edu\/user-html\/blumberg\/?p=164"},"modified":"2018-09-13T19:33:35","modified_gmt":"2018-09-13T19:33:35","slug":"critical-quadrupole-fluctuations-and-collective-modes-in-iron-pnictide-superconductors","status":"publish","type":"post","link":"https:\/\/girsh.rutgers.edu\/index.php\/2016\/04\/21\/critical-quadrupole-fluctuations-and-collective-modes-in-iron-pnictide-superconductors\/","title":{"rendered":"Critical quadrupole fluctuations and collective modes in iron pnictide superconductors"},"content":{"rendered":"<p style=\"text-align: left;\"><strong> <img fetchpriority=\"high\" decoding=\"async\" class=\" wp-image-182 alignright\" src=\"http:\/\/cgisvr.physics.rutgers.edu\/user-html\/blumberg\/wp-content\/uploads\/2016\/04\/VernerPaperImage.png\" alt=\"VernerPaperImage\" width=\"319\" height=\"262\" \/>Authors:<\/strong> V. K. Thorsm\u00f8lle, M. Khodas, Z. P. Yin, Chenglin Zhang, S. V. Carr, Pengcheng Dai, and G. Blumberg<\/p>\n<p><strong>Abstract:<\/strong>\u00a0The multiband nature of iron pnictides gives rise to a rich temperature-doping phase diagram of competing orders and a plethora of collective phenomena. At low dopings, the tetragonal-to-orthorhombic structural transition is closely followed by a spin-density-wave transition both being in close proximity to the superconducting phase. A key question is the nature of high-T<sub>c<\/sub> superconductivity and its relation to orbital ordering and magnetism. Here we study the NaFe<sub>1-x<\/sub>Co<sub>x<\/sub>As superconductor using polarization-resolved Raman spectroscopy. The Raman susceptibility displays critical enhancement of nonsymmetric charge fluctuations across the entire phase diagram, which are precursors to a d-wave Pomeranchuk instability at temperature \u03b8(x). The charge fluctuations are interpreted in terms of quadrupole interorbital excitations in which the electron and hole Fermi surfaces breathe in-phase. Below T<sub>c<\/sub>, the critical fluctuations acquire coherence and undergo a metamorphosis into a coherent in-gap mode of extraordinary strength.<\/p>\n<ul>\n<li><em><a href=\"http:\/\/cgisvr.physics.rutgers.edu\/user-html\/blumberg\/wp-content\/uploads\/2016\/04\/PhysRevB.93.054515.pdf\">Read here<\/a><\/em><\/li>\n<li><del><\/del><em><a href=\"http:\/\/journals.aps.org\/prb\/abstract\/10.1103\/PhysRevB.93.054515\" target=\"_blank\">Paper available from Physics Review B<\/a><\/em><\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Authors: V. K. Thorsm\u00f8lle, M. Khodas, Z. P. Yin, Chenglin Zhang, S. V. Carr, Pengcheng Dai, and G. Blumberg Abstract:\u00a0The multiband nature of iron pnictides gives rise to a rich temperature-doping phase diagram of competing orders and a plethora of collective phenomena. At low dopings, the tetragonal-to-orthorhombic structural transition is closely followed by a spin-density-wave &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"\" href=\"https:\/\/girsh.rutgers.edu\/index.php\/2016\/04\/21\/critical-quadrupole-fluctuations-and-collective-modes-in-iron-pnictide-superconductors\/\"> <span class=\"screen-reader-text\">Critical quadrupole fluctuations and collective modes in iron pnictide superconductors<\/span> Read More &raquo;<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"_links":{"self":[{"href":"https:\/\/girsh.rutgers.edu\/index.php\/wp-json\/wp\/v2\/posts\/164"}],"collection":[{"href":"https:\/\/girsh.rutgers.edu\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/girsh.rutgers.edu\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/girsh.rutgers.edu\/index.php\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/girsh.rutgers.edu\/index.php\/wp-json\/wp\/v2\/comments?post=164"}],"version-history":[{"count":8,"href":"https:\/\/girsh.rutgers.edu\/index.php\/wp-json\/wp\/v2\/posts\/164\/revisions"}],"predecessor-version":[{"id":803,"href":"https:\/\/girsh.rutgers.edu\/index.php\/wp-json\/wp\/v2\/posts\/164\/revisions\/803"}],"wp:attachment":[{"href":"https:\/\/girsh.rutgers.edu\/index.php\/wp-json\/wp\/v2\/media?parent=164"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/girsh.rutgers.edu\/index.php\/wp-json\/wp\/v2\/categories?post=164"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/girsh.rutgers.edu\/index.php\/wp-json\/wp\/v2\/tags?post=164"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}