{"_buckets": {"deposit": "67d8fda1-b282-41dc-a8d1-d611e66bee5b"}, "_deposit": {"created_by": 1, "id": "674", "owners": [1], "pid": {"revision_id": 0, "type": "depid", "value": "674"}, "status": "published"}, "_oai": {"id": "oai:ir.soken.ac.jp:00000674", "sets": ["15"]}, "author_link": ["0", "0", "0"], "item_1_biblio_info_21": {"attribute_name": "書誌情報（ソート用）", "attribute_value_mlt": [{"bibliographicIssueDates": {"bibliographicIssueDate": "2006-09-29", "bibliographicIssueDateType": "Issued"}, "bibliographic_titles": [{}]}]}, "item_1_creator_2": {"attribute_name": "著者名", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "邱, 宇"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_creator_3": {"attribute_name": "フリガナ", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "クイユ"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_1_date_granted_11": {"attribute_name": "学位授与年月日", "attribute_value_mlt": [{"subitem_dategranted": "2006-09-29"}]}, "item_1_degree_grantor_5": {"attribute_name": "学位授与機関", "attribute_value_mlt": [{"subitem_degreegrantor": [{"subitem_degreegrantor_name": "総合研究大学院大学"}]}]}, "item_1_degree_name_6": {"attribute_name": "学位名", "attribute_value_mlt": [{"subitem_degreename": "博士（理学）"}]}, "item_1_description_1": {"attribute_name": "ID", "attribute_value_mlt": [{"subitem_description": "2006509", "subitem_description_type": "Other"}]}, "item_1_description_12": {"attribute_name": "要旨", "attribute_value_mlt": [{"subitem_description": "　Since some 3D type perovkite compounds have been found in the experiments to\u003cbr /\u003egive gigantic dielectric constant, in contrast to the ordinary dielectrics, its\u003cbr /\u003eunderlying microscopic mechanism has attractted much attention in the field of\u003cbr /\u003esolid state theory. As is well-known, the ferroelectric modes play an important roll\u003cbr /\u003ein the dielectric property, transportation and phase transition or these materials.\u003cbr /\u003eMany efforts were already performed on the connection of this ferroelectric mode\u003cbr /\u003ewith the quartic or sextic anharmonic oscillators. ln experiment, glgantic\u003cbr /\u003ephoto-enhancements of the electronic conductivity and the dielectric constant have\u003cbr /\u003erecently been observed in SrTiO3. lt was also pointed out that, this dielectric\u003cbr /\u003eenhancement remains to exist only under the ultraviolet (UV) illumination, while\u003cbr /\u003evanishes as the illumination is turned off. As for the photo-induced electronic\u003cbr /\u003econduction in SrTiO\u003csub\u003e3\u003c/sub\u003e, it is expected to be an alternative mechanism from that of the\u003cbr /\u003eordinary field induced one in metallic systems. However, the microscopic origin of\u003cbr /\u003ethese photo-induced phenomena has not yet been clarified theoretically. Thus, this\u003cbr /\u003eis just the motivation of the present study.\u003cbr /\u003e　We will give a short introduction to the soft mode theory in the\u003cbr /\u003esecond chapter since our work will be mainly based on this theory.\u003cbr /\u003eThe spatial structure and the electronic property of this　3D\u003cbr /\u003eperovskite. SrTi0\u003csub\u003e3\u003c/sub\u003e, are also stated. since we will focus our efforts\u003cbr /\u003eonly on this compound in the present work. Some key points of the\u003cbr /\u003eprevious studies on　the fundamental properties of SrTiO\u003csub\u003e3\u003c/sub\u003e, are\u003cbr /\u003esummerized as well. =n Chapter 3, a detailed illustration is given\u003cbr /\u003eto the Super-Para-Electric (SPE) large polarons, from the set-up of\u003cbr /\u003ethe cheoretic model to the numerical calculatlons, and ends up with\u003cbr /\u003ethe impurity effect on this polaron. Combining the experimentally\u003cbr /\u003eobserved dielectrlc and conductive properties with previous\u003cbr /\u003etheoretical researches on the model for this crystal, we give a further\u003cbr /\u003einvestigation into the model and come up with a new model for the\u003cbr /\u003ephoto excited state of the crystal.  By which, we can adiabatically\u003cbr /\u003eobtain the corresponding energy surface and find all the metastable\u003cbr /\u003estates on it. With the investigation of each of such states,　We can\u003cbr /\u003efind its connection with the dielectric and conductive property of\u003cbr /\u003ethis crystal･ We also give an investigation into the most stable\u003cbr /\u003equasiparticle state for the many electron system within the adeabatic\u003cbr /\u003emethod and give a description to the possible lattice configurations\u003cbr /\u003efor the photo excited state of the electron and phonon coupling system.\u003cbr /\u003eThen it is followed by Chapter 4, the appllcations of this SPE polaron\u003cbr /\u003etheory in the interpretation of the photo-induced giant dielectric\u003cbr /\u003econstant and electronic conductivity. We will first discuss one of\u003cbr /\u003ethe fundamental problems for phonons, phonon softening or phonon\u003cbr /\u003ehardening with the introduction of e-p coupling. Then we will apply\u003cbr /\u003eour SPE large polaron theory to the experimentally observed static\u003cbr /\u003edielectric enhancement in srTiO\u003csub\u003e3\u003c/sub\u003e, clarifying the microscopic origin \u003cbr /\u003eof this photo-induced phase transition. In the following, we will\u003cbr /\u003egive a phenomenological interpretation to the experimentally reported\u003cbr /\u003emetallic conduction in SrTiO\u003csub\u003e3\u003c/sub\u003e by studying the translational property\u003cbr /\u003eof the polarons. In Chapter 5, we will discuss the relaxation process\u003cbr /\u003eof the lattice after the photo-excitation. It has already been studied\u003cbr /\u003ethat for polymers, the formation of the polaron or exciton is an\u003cbr /\u003eultra-fast process. \u003csup\u003e[6l]\u003c/sup\u003e In experiment, these states could be detected\u003cbr /\u003eand predicted from the spectra. However, by virtue of the molecular\u003cbr /\u003edynamics theory, the information of the lattice configuration as well\u003cbr /\u003eas the electronic state can be traced so as to compare with the\u003cbr /\u003eenergetic evolution. Then, the lattice relaxation process could be\u003cbr /\u003erecognized more clearly. We will first give a deschption to the \u003cbr /\u003emolecular dynamics theory for the e-p interacting system. Then, we\u003cbr /\u003ewill apply this method to SrTiO\u003csub\u003e3\u003c/sub\u003e and give some detailed descriptions\u003cbr /\u003eabout the relaxation process in this crystal. We will show the\u003cbr /\u003eformation of the SPE large polaron is an ultra-fast process of about\u003cbr /\u003eseveral picoseconds,　and how the electron and phonon interaction\u003cbr /\u003esystem releases its energy so as to reach its new stable state. The\u003cbr /\u003einfluence of the electron and phonon interaction strength and the\u003cbr /\u003esize of the electron and phonon coupling system on the relaxation\u003cbr /\u003eprocess will be shown. A summary of all the conclusions of　these\u003cbr /\u003estudies is given at Chapter　6.", "subitem_description_type": "Other"}]}, "item_1_description_7": {"attribute_name": "学位記番号", "attribute_value_mlt": [{"subitem_description": "総研大甲第989号", "subitem_description_type": "Other"}]}, "item_1_select_14": {"attribute_name": "所蔵", "attribute_value_mlt": [{"subitem_select_item": "有"}]}, "item_1_select_8": {"attribute_name": "研究科", "attribute_value_mlt": [{"subitem_select_item": "高エネルギー加速器科学研究科"}]}, "item_1_select_9": {"attribute_name": "専攻", "attribute_value_mlt": [{"subitem_select_item": "13 物質構造科学専攻"}]}, "item_1_text_10": {"attribute_name": "学位授与年度", "attribute_value_mlt": [{"subitem_text_value": "2006"}]}, "item_creator": {"attribute_name": "著者", "attribute_type": "creator", "attribute_value_mlt": [{"creatorNames": [{"creatorName": "QIU, Yu", "creatorNameLang": "en"}], "nameIdentifiers": [{"nameIdentifier": "0", "nameIdentifierScheme": "WEKO"}]}]}, "item_files": {"attribute_name": "ファイル情報", "attribute_type": "file", "attribute_value_mlt": [{"accessrole": "open_date", "date": [{"dateType": "Available", "dateValue": "2016-02-17"}], "displaytype": "simple", "download_preview_message": "", "file_order": 0, "filename": "甲989_要旨.pdf", "filesize": [{"value": "265.9 kB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 265900.0, "url": {"label": "要旨・審査要旨", "url": "https://ir.soken.ac.jp/record/674/files/甲989_要旨.pdf"}, "version_id": "4542bfbc-ae83-4a24-b6a8-58f50a69a08f"}, {"accessrole": "open_date", "date": [{"dateType": "Available", "dateValue": "2016-02-17"}], "displaytype": "simple", "download_preview_message": "", "file_order": 1, "filename": "甲989_本文.pdf", "filesize": [{"value": "4.9 MB"}], "format": "application/pdf", "future_date_message": "", "is_thumbnail": false, "licensetype": "license_11", "mimetype": "application/pdf", "size": 4900000.0, "url": {"label": "本文", "url": "https://ir.soken.ac.jp/record/674/files/甲989_本文.pdf"}, "version_id": "936fb837-dafc-4109-b8b8-33a704a4ca80"}]}, "item_language": {"attribute_name": "言語", "attribute_value_mlt": [{"subitem_language": "eng"}]}, "item_resource_type": {"attribute_name": "資源タイプ", "attribute_value_mlt": [{"resourcetype": "thesis", "resourceuri": "http://purl.org/coar/resource_type/c_46ec"}]}, "item_title": "Dual Electron-phonon Coupling Model for Giant Photoenhancements of  Dielectric Constant and Electronic Conductivity in SrTiO3", "item_titles": {"attribute_name": "タイトル", "attribute_value_mlt": [{"subitem_title": "Dual Electron-phonon Coupling Model for Giant Photoenhancements of  Dielectric Constant and Electronic Conductivity in SrTiO3"}, {"subitem_title": "Dual Electron-phonon Coupling Model for Giant Photoenhancements of  Dielectric Constant and Electronic Conductivity in SrTiO3", "subitem_title_language": "en"}]}, "item_type_id": "1", "owner": "1", "path": ["15"], "permalink_uri": "https://ir.soken.ac.jp/records/674", "pubdate": {"attribute_name": "公開日", "attribute_value": "2010-02-22"}, "publish_date": "2010-02-22", "publish_status": "0", "recid": "674", "relation": {}, "relation_version_is_last": true, "title": ["Dual Electron-phonon Coupling Model for Giant Photoenhancements of  Dielectric Constant and Electronic Conductivity in SrTiO3"], "weko_shared_id": 1}