{"id":36199,"date":"1998-01-01T00:00:00","date_gmt":"1998-01-01T00:00:00","guid":{"rendered":"https:\/\/www.deberes.net\/tesis\/sin-categoria\/la-transicion-metal-aislante-en-los-oxidos-rnio3-rland-y-sm-sustitucion-de-cobre-y-cobalto-en-la-subred-de-niquel\/"},"modified":"1998-01-01T00:00:00","modified_gmt":"1998-01-01T00:00:00","slug":"la-transicion-metal-aislante-en-los-oxidos-rnio3-rland-y-sm-sustitucion-de-cobre-y-cobalto-en-la-subred-de-niquel","status":"publish","type":"post","link":"https:\/\/www.deberes.net\/tesis\/fisica\/la-transicion-metal-aislante-en-los-oxidos-rnio3-rland-y-sm-sustitucion-de-cobre-y-cobalto-en-la-subred-de-niquel\/","title":{"rendered":"La transicion metal-aislante en los oxidos rnio3, r=la,nd y sm. sustitucion de cobre y cobalto en la subred de niquel"},"content":{"rendered":"<h2>Tesis doctoral de <strong>  Perez Cacho Jorge  J. <\/strong><\/h2>\n<p>El estudio de los \u00f3xidos de metales de transici\u00f3n rmo3 ha sufrido un fuerte impulso tras el descubrimiento de la superconductividad de alta temperatura en \u00f3xidos de cobre o la magnetorresistencia gigante en \u00f3xidos de manganeso, compuestos con futuras aplicaciones tecnol\u00f3gicas. El inter\u00e9s cient\u00edfico ha llevado tambi\u00e9n el estudio de las interacciones, propiedades y estructuras electr\u00f3nicas desde un punto de vista b\u00e1sico en estos \u00f3xidos. Dentro de este marco se encuadra esta memoria.  se ha estudiado la s\u00edntesis y caracterizaci\u00f3n (propiedades estructurales, de transporte, magn\u00e9ticas y calorim\u00e9tricas) de los \u00f3xidos rnio3 y rni1-xmxo3, con r=la. Nd y sm, m=co y cu. Se han establecido sus diagramas de fase.  los \u00f3xidos rnio3 cristalizan en estructuras distorsionadas de la perovskita c\u00fabica. Presentan una transici\u00f3n metal-aislante (tmi) en funci\u00f3n de la temperatura y del tama\u00f1o de la tierra rara. Para r=nd aparece un orden af junto a tmi, para r=sm el orden magn\u00e9tico se produce a un temperatura tn inferior. En la regi\u00f3n met\u00e1lica el gas de electrones presenta una alta correlaci\u00f3n, interpretaci\u00f3n dada a los valores de  pauli, , entrop\u00eda de la transici\u00f3n af y del t\u00e9rmino t2 de resistividad. Al sustituir n\u00edquel por cobre o cobalto, rni1-xmxo3, aparece un brusco descenso de tmi. Las se\u00f1ales de correlaci\u00f3n electr\u00f3nica tambi\u00e9n disminuyen al aumentar la sustituci\u00f3n. Se pasa de valores de  pauli 100 en el ndi0.95cu0.05o3 a  pauli 7 en el lani0.4cu0.6o3.  para explicar la tmi se propone la competencia entre la estabilidad aportada por un estado met\u00e1lico (caracterizado por la anchura de la banda de conducci\u00f3n, w) y el efecto de correlaci\u00f3n electr\u00f3nica que tiende a localizar los portadores (caracterizado por la repulsi\u00f3n intra-at\u00f3mica de coulomb, upd-pd). En resumen, tmi es una transici\u00f3n \u00abtipo mott\u00bb. Cuando x 0.3 se ha introducido tambi\u00e9n el concepto de desorden estructural, apareciendo los umbrales de<\/p>\n<p>&nbsp;<\/p>\n<h3>Datos acad\u00e9micos de la tesis doctoral \u00ab<strong>La transicion metal-aislante en los oxidos rnio3, r=la,nd y sm. sustitucion de cobre y cobalto en la subred de niquel<\/strong>\u00ab<\/h3>\n<ul>\n<li><strong>T\u00edtulo de la tesis:<\/strong>\u00a0 La transicion metal-aislante en los oxidos rnio3, r=la,nd y sm. sustitucion de cobre y cobalto en la subred de niquel <\/li>\n<li><strong>Autor:<\/strong>\u00a0  Perez Cacho Jorge  J. <\/li>\n<li><strong>Universidad:<\/strong>\u00a0 Zaragoza<\/li>\n<li><strong>Fecha de lectura de la tesis:<\/strong>\u00a0 01\/01\/1998<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n<h3>Direcci\u00f3n y tribunal<\/h3>\n<ul>\n<li><strong>Director de la tesis<\/strong>\n<ul>\n<li>Joaquin Garcia Ruiz<\/li>\n<\/ul>\n<\/li>\n<li><strong>Tribunal<\/strong>\n<ul>\n<li>Presidente del tribunal: Ricardo Ibarra <\/li>\n<li>Josep Fontcuberta Gri\u00f1\u00f3 (vocal)<\/li>\n<li>Jos\u00e9 Rivas (vocal)<\/li>\n<li>Antonio Alonso Jose (vocal)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Tesis doctoral de Perez Cacho Jorge J. El estudio de los \u00f3xidos de metales de transici\u00f3n rmo3 ha sufrido un [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"footnotes":""},"categories":[332,199,1008,1126,13610],"tags":[25888,72292,7132,21538,95999,96000],"class_list":["post-36199","post","type-post","status-publish","format-standard","hentry","category-ciencias-tecnologicas","category-fisica","category-fisica-del-estado-solido","category-tecnologia-de-materiales","category-zaragoza","tag-antonio-alonso-jose","tag-joaquin-garcia-ruiz","tag-jose-rivas","tag-josep-fontcuberta-grino","tag-perez-cacho-jorge-j","tag-ricardo-ibarra"],"_links":{"self":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts\/36199","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/comments?post=36199"}],"version-history":[{"count":0,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/posts\/36199\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/media?parent=36199"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/categories?post=36199"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.deberes.net\/tesis\/wp-json\/wp\/v2\/tags?post=36199"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}