{"id":20865,"date":"2011-09-21T12:56:23","date_gmt":"2011-09-21T09:56:23","guid":{"rendered":"http:\/\/www.fyysika.ee\/uudised\/?p=20865"},"modified":"2011-09-23T08:46:59","modified_gmt":"2011-09-23T05:46:59","slug":"grafeenmullikestest-laatsed","status":"publish","type":"post","link":"https:\/\/www.fyysika.ee\/?p=20865","title":{"rendered":"Grafeenmullikestest l\u00e4\u00e4tsed"},"content":{"rendered":"

Grafeeni t\u00f6\u00f6p\u00f5ld on lai. Briti teadlased t\u00f6\u00f6tavad v\u00e4ikeste grafeenist mullikeste kallal, mille tulevikurakenduste hulka v\u00f5ib kuuluda muudetava fookuskaugusega inimsilma matkiv optiline l\u00e4\u00e4ts. Esimese sammuna n\u00e4itasid teadlased, et mulli k\u00f5verust saab valise elektriv\u00e4lja abil moonutada.<\/strong><\/p>\n

\"\"<\/a>

Aatomj\u00f5u mikroskoobi (ATM) kujutis 3 \u00b5m (10-6 m) grafeenmullist.<\/p><\/div>\n

Grafeen on \u00fche aatomkihi paksune s\u00fcsinikup\u00f5hine materjal, millel on plejaad ainulaadseid mehaanilisi ja elektrilisi omadusi. Materjali saab \u00fches sihis pikemaks venitada kuni 20 %. Elastsuse t\u00f5ttu ongi v\u00f5imalik mullide valmistamine. Grafeen laseb l\u00e4bi valgust, ent peab kinni enamiku gaase ja vedelikke, mille t\u00f5ttu sobib materjal v\u00e4ga h\u00e4sti l\u00e4\u00e4tsede valmistamiseks.<\/p>\n

Isefokusseerivaid l\u00e4\u00e4tsesid kasutatakse prillides, veebikaamerates ja mobiiltelefonide fotosilmades. Tavaliselt p\u00f5hinevad need lahendused l\u00e4bipaistvatel vedelkristallidel. Vedelkristallidel p\u00f5hinevad isefokusseerivad seadmed t\u00f6\u00f6tavad h\u00e4sti, aga nende valmistamine on keerukas ja seet\u00f5ttu kallis. Sarnaste grafeenseadmete valmistamine oleks odavam. Puuduv l\u00fcli on grafeeni t\u00f6\u00f6stuslik tootmine.<\/p>\n

2010. aasta Nobeli f\u00fc\u00fcsika preemia laureaatide Andre Geimi ja Konstantin Novoselovi ning Manchesteri \u00dclikooli teadlaste koost\u00f6\u00f6 tulemusena on valminud v\u00e4ikesed grafeenseadmed, mida oleks v\u00f5imalik adaptiivsete optilistes s\u00fcsteemides kasutada. Seadmed p\u00f5hinevad r\u00e4nioksiid pinnale valmistatud suurtel grafeenhelmestel. Helmeste sadestamisel on v\u00f5imalik kahe materjali vaheline \u00f5hk vangistada, mille tulemusel tekib elastsesse grafeeni kihti mull. Grafeenmullid on v\u00e4ga stabiilsed. Mullide l\u00e4bim\u00f5\u00f5t varieerub m\u00f5nek\u00fcmnest nanomeetrist m\u00f5nek\u00fcmne mikromeetrini.<\/p>\n

Grafeenmullide k\u00fclge kinnitati trasnsistori \u00fchendustele sarnaselt titaaniumi- ja kuldelektroodid. Paisule rakendatud -35 V kuni 35 V pinge vahemikus j\u00e4lgiti aatomj\u00f5u mikroskoobi (Atomic Force Microscope, AFM) all grafeenmulli k\u00f5veruse t\u00f5usmist ja langemist.<\/p>\n

Teadlaste s\u00f5nul on \u00fcks v\u00f5imalusi t\u00f6\u00f6tava l\u00e4\u00e4tse saamiseks grafeenimullide t\u00e4itmine v\u00f5i nende pinna katmine suure murdumisn\u00e4itajaga vedelikuga. Lisaks uuritakse v\u00f5imalusi mullide pinnale keerukamate reljeefide loomiseks ja juhtimiseks.<\/p>\n

Allikas: PhysicsWorld<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

Grafeeni t\u00f6\u00f6p\u00f5ld on lai. Briti teadlased t\u00f6\u00f6tavad v\u00e4ikeste grafeenist mullikeste kallal, mille tulevikurakenduste hulka v\u00f5ib kuuluda muudetava fookuskaugusega inimsilma matkiv optiline l\u00e4\u00e4ts. Esimese sammuna n\u00e4itasid teadlased, et mulli k\u00f5verust saab valise elektriv\u00e4lja abil moonutada. Grafeen on \u00fche aatomkihi paksune s\u00fcsinikup\u00f5hine materjal, millel on plejaad ainulaadseid mehaanilisi ja elektrilisi omadusi. Materjali saab \u00fches sihis pikemaks venitada […]<\/p>\n","protected":false},"author":449,"featured_media":20866,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[16],"tags":[45],"class_list":{"0":"post-20865","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-teadusuudis","8":"tag-grafeengrafaan","9":"entry"},"_links":{"self":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts\/20865","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/users\/449"}],"replies":[{"embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=20865"}],"version-history":[{"count":0,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts\/20865\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/media\/20866"}],"wp:attachment":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=20865"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=20865"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=20865"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}