{"id":{"repo_id":"greece","oai_identifier":"oai:10442/1364"},"canonical_url":"https://search.dev.ndltd.org/etd/greece/oai:10442/1364","repository":{"repo_id":"greece","name":"Greek National Archive of PhD Theses","base_url":"https://phdtheses.ekt.gr/eadd_oai/request"},"display":{"title":"Οπτικές ιδιότητες του αραιού μαγνητικού ημιαγωγού Ζn₁₋ₓΜnₓS","abstract":"In this thesis, a systematic Raman and luminescence study of the diluted magnetic semiconductor Ζn₁₋ₓΜnₓS has been carried out for concentrations x=0.03-0.5. The effects on the spectra of high-low temperature (T=20-1300K), hydrostatic pressure (p=0-5 GPa), and the excitation wavelength (λ=3507-6764 A) have been examined in detail. Based on the luminescence spectra the dependence of the emission bands on the external parameters has been delineated. Besides, the characteristic phase transition that appears at high hydrostatic pressures has been studied for all concentrations. The Raman spectra have supplied the optical phonon frequencies of the lattice and the impurity induced modes. From the concentration dependence of the optical modes, an 'one-mode' behavior has been established. By applying the configuration coordinate model, the lattice properties have been related to the electronic transitions and the parameters of the model have been induced. It was demonstrated that the optical transitions are coupled only to the impurity induced modes.","abstract_html":"In this thesis, a systematic Raman and luminescence study of the diluted magnetic semiconductor Ζn₁₋ₓΜnₓS has been carried out for concentrations x=0.03-0.5. The effects on the spectra of high-low temperature (T=20-1300K), hydrostatic pressure (p=0-5 GPa), and the excitation wavelength (λ=3507-6764 A) have been examined in detail. Based on the luminescence spectra the dependence of the emission bands on the external parameters has been delineated. Besides, the characteristic phase transition that appears at high hydrostatic pressures has been studied for all concentrations. The Raman spectra have supplied the optical phonon frequencies of the lattice and the impurity induced modes. From the concentration dependence of the optical modes, an 'one-mode' behavior has been established. By applying the configuration coordinate model, the lattice properties have been related to the electronic transitions and the parameters of the model have been induced. It was demonstrated that the optical transitions are coupled only to the impurity induced modes.","abstract_has_math":false,"creators":["Anastassiadou, Anastasia","Αναστασιάδου, Αναστασία"],"institution":"National Technical University of Athens (NTUA)","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1990,"date_issued":"1990","date_published":"1990","updated_at":"2026-07-24T02:24:52Z","subjects":["Ημιαγωγοί","Μαγνητικά υλικά","Οπτική","Σκέδαση Raman","Φωταύγεια","Luminescence","Optical","Raman scattering","Semiconductor","Semimagnetic materials","Φυσικές Επιστήμες","Φυσική","Natural Sciences","Physical Sciences"],"languages":["gre"],"rights":[],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["10.12681/eadd/1364"],"render_values":[{"text":"10.12681/eadd/1364","href":"https://doi.org/10.12681/eadd/1364","code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10442/hedi/1364","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Anastassiadou, Anastasia","Αναστασιάδου, Αναστασία"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["1990"]},{"key":"dc:publisher","label":"Institution","values":["National Technical University of Athens (NTUA)","Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ)"]},{"key":"dc:type","label":"Dc Type","values":["PhD Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Ημιαγωγοί","Μαγνητικά υλικά","Οπτική","Σκέδαση Raman","Φωταύγεια","Luminescence","Optical","Raman scattering","Semiconductor","Semimagnetic materials","Φυσικές Επιστήμες","Φυσική","Natural Sciences","Physical Sciences"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["gre"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["10.12681/eadd/1364","http://hdl.handle.net/10442/hedi/1364"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["In this thesis, a systematic Raman and luminescence study of the diluted magnetic semiconductor Ζn₁₋ₓΜnₓS has been carried out for concentrations x=0.03-0.5. The effects on the spectra of high-low temperature (T=20-1300K), hydrostatic pressure (p=0-5 GPa), and the excitation wavelength (λ=3507-6764 A) have been examined in detail. Based on the luminescence spectra the dependence of the emission bands on the external parameters has been delineated. Besides, the characteristic phase transition that appears at high hydrostatic pressures has been studied for all concentrations. The Raman spectra have supplied the optical phonon frequencies of the lattice and the impurity induced modes. From the concentration dependence of the optical modes, an 'one-mode' behavior has been established. By applying the configuration coordinate model, the lattice properties have been related to the electronic transitions and the parameters of the model have been induced. It was demonstrated that the optical transitions are coupled only to the impurity induced modes.","Σε αυτήν την διατριβή έγινε συστηματική μελέτη των φασμάτων φωταύγειας και Raman του αραιού μαγνητικού ημιαγωγού Ζn₁₋ₓΜnₓS για το διάστημα συγκεντρώσεων x=0.03-0.5, κάτω από συνθήκες μεταβλητών εξωτερικών παραμέτρων. Συγκεκριμένα μελετήθηκε η επίδραση στα φάσματα της θερμοκρασίας (Τ=20-1300 Κ), της υδροστατικής πίεσης (p=0-15 GPa) και του μήκους κύματος (λ=3507-6764 Α). Όσον αφορά τα φάσματα φωταύγειας προσδιορίσθηκαν οι ζώνες εκπομπής και η συμπεριφορά τους σαν συνάρτηση των εξωτερικών παραμέτρων και της συγκέντρωσης x. Προσδιορίσθηκαν επίσης τα χαρακτηριστικά της δομικής μεταβολής φάσης που παρατηρείται στο υλικό αυτό, σε υψηλές υδροστατικές πιέσεις. Όσον αφορά τα φάσματα Raman προσδιορίστηκαν οι συχνότητες των οπτικών φωτονίων και των ρυθμών ταλάντωσης των επαγόμενων από την πρόσμειξη. Προσδιορίσθηκε επίσης η συμπεριφορά 'ενός ρυθμού' των οπτικών φωνονίων του κέντρου της ζώνης, σαν συνάρτηση της συγκέντρωσης x. Τέλος εφαρμόστηκε θεωρητικό μοντέλο (configuration coordinate model), έτσι ώστε να συνδεθούν οι ηλεκτρονικές (οπτικές) με τις φωνονιακές ιδιότητες του υλικού. Με αυτόν τον τρόπο προσδιορίσθηκαν οι παράμετροι του μοντέλου και αποδείχθηκε ότι όλοι οι ρυθμοί ταλάντωσης, οι επαγόμενοι από τις προσμείξεις, είναι έντονα συζευγμένοι με τις οπτικές μεταπτώσεις του υλικού."]},{"key":"dc:title","label":"Title","values":["Οπτικές ιδιότητες του αραιού μαγνητικού ημιαγωγού Ζn₁₋ₓΜnₓS","Optical properties of the semi-magnetic semi-conductor Ζn₁₋ₓΜnₓS"]}]}],"canonical_facts":{"dc:creator":["Anastassiadou, Anastasia","Αναστασιάδου, Αναστασία"],"dc:date":["1990"],"dc:description":["In this thesis, a systematic Raman and luminescence study of the diluted magnetic semiconductor Ζn₁₋ₓΜnₓS has been carried out for concentrations x=0.03-0.5. The effects on the spectra of high-low temperature (T=20-1300K), hydrostatic pressure (p=0-5 GPa), and the excitation wavelength (λ=3507-6764 A) have been examined in detail. Based on the luminescence spectra the dependence of the emission bands on the external parameters has been delineated. Besides, the characteristic phase transition that appears at high hydrostatic pressures has been studied for all concentrations. The Raman spectra have supplied the optical phonon frequencies of the lattice and the impurity induced modes. From the concentration dependence of the optical modes, an 'one-mode' behavior has been established. By applying the configuration coordinate model, the lattice properties have been related to the electronic transitions and the parameters of the model have been induced. It was demonstrated that the optical transitions are coupled only to the impurity induced modes.","Σε αυτήν την διατριβή έγινε συστηματική μελέτη των φασμάτων φωταύγειας και Raman του αραιού μαγνητικού ημιαγωγού Ζn₁₋ₓΜnₓS για το διάστημα συγκεντρώσεων x=0.03-0.5, κάτω από συνθήκες μεταβλητών εξωτερικών παραμέτρων. Συγκεκριμένα μελετήθηκε η επίδραση στα φάσματα της θερμοκρασίας (Τ=20-1300 Κ), της υδροστατικής πίεσης (p=0-15 GPa) και του μήκους κύματος (λ=3507-6764 Α). Όσον αφορά τα φάσματα φωταύγειας προσδιορίσθηκαν οι ζώνες εκπομπής και η συμπεριφορά τους σαν συνάρτηση των εξωτερικών παραμέτρων και της συγκέντρωσης x. Προσδιορίσθηκαν επίσης τα χαρακτηριστικά της δομικής μεταβολής φάσης που παρατηρείται στο υλικό αυτό, σε υψηλές υδροστατικές πιέσεις. Όσον αφορά τα φάσματα Raman προσδιορίστηκαν οι συχνότητες των οπτικών φωτονίων και των ρυθμών ταλάντωσης των επαγόμενων από την πρόσμειξη. Προσδιορίσθηκε επίσης η συμπεριφορά 'ενός ρυθμού' των οπτικών φωνονίων του κέντρου της ζώνης, σαν συνάρτηση της συγκέντρωσης x. Τέλος εφαρμόστηκε θεωρητικό μοντέλο (configuration coordinate model), έτσι ώστε να συνδεθούν οι ηλεκτρονικές (οπτικές) με τις φωνονιακές ιδιότητες του υλικού. Με αυτόν τον τρόπο προσδιορίσθηκαν οι παράμετροι του μοντέλου και αποδείχθηκε ότι όλοι οι ρυθμοί ταλάντωσης, οι επαγόμενοι από τις προσμείξεις, είναι έντονα συζευγμένοι με τις οπτικές μεταπτώσεις του υλικού."],"dc:identifier":["10.12681/eadd/1364","http://hdl.handle.net/10442/hedi/1364"],"dc:language":["gre"],"dc:publisher":["National Technical University of Athens (NTUA)","Εθνικό Μετσόβιο Πολυτεχνείο (ΕΜΠ)"],"dc:subject":["Ημιαγωγοί","Μαγνητικά υλικά","Οπτική","Σκέδαση Raman","Φωταύγεια","Luminescence","Optical","Raman scattering","Semiconductor","Semimagnetic materials","Φυσικές Επιστήμες","Φυσική","Natural Sciences","Physical Sciences"],"dc:title":["Οπτικές ιδιότητες του αραιού μαγνητικού ημιαγωγού Ζn₁₋ₓΜnₓS","Optical properties of the semi-magnetic semi-conductor Ζn₁₋ₓΜnₓS"],"dc:type":["PhD Thesis"]},"updated_at":"2026-07-24T02:24:52Z"}