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1	The Study of Ferromagnetic(La0.67Ca0.33MnO3)-Antiferromagnetic(La0.67Sr1.33MnO4)multi-layer Growth and Properties Di, Chun-I 11 August 2004 (has links) (La0.67Sr0.33MnO3)£»(SrO), LSMO214(n=1) in short, is 2-D magnetic insulator with a structure very similar to the 3D La0.67Sr0.33MnO3 and La0.67Ca0.33MnO3, 113(n=1) in short, which consists of superstructure of a subsequent magnetic layers and insulating layers. Forming a single 214 phase bulk is not easy, a mix phase of 2<n<¡Û compounds is usually seen. Due to the lattice mismatch between Substrate and bulk,strain has been an important factors of magnetic resistance and electrical properties. Studying single layer and multi-layer films,we find because the small of growth condition scope and lattice mismatch,the LSMO214 films consists mix phases of higher n. LSMO(214) LCMO(113)
2	Zusammenspiel von Ladungs-, Gitter- und magnetischen Ordnungen in hochdotierten LCMO Schichten / Interplay of charge-, lattice and magnetic ordering in overdoped LCMO films Fischgrabe, Florian 16 June 2015 (has links) No description available. 530 Physik (PPN621336750) LCMO Raman spectroscopy charge ordering
3	The study of charge ordering in colossal magnetoresistance Lee, Kung-Chieh 09 January 2006 (has links) Hole-doped maganite with middle to narrow bandwidth La1-xCaxMnO3 was extensively studied because of its colossal magnetoresistance (CMR) characteristic under a magnetic field. These kind of materials show un- common magnetic and electric properties. The charge order phase only happens to the region x> 0.5, and along with decreasing temperature, its phase goes from para-insulator to charge-ordered then to antiferromagne- tism. In our studies, we apply correlation function of Green¡¦s function to LCMO and get susceptibility of charge and spin. Then we can get the cri- tical value of Coulomb repulsion inside the material by substituting the experimental values of phase transition temperature. This critical values is the key point of charge-ordered. Then we can also get the size of char- ge gap which decides the stability of charge-ordered phase. After know- ing the Coulomb repulsion and charge gap, we can picture the relation of inside and on-site Coulomb repulsion qualitatively while the transition happens. Here the on-site Coulomb repulsion means to the Hund¡¦s coupl- ing between d electrons. And by this we¡¦ll understand the physics inside CMR materials. colossal magnetoresistance CMR Jahn-Teller distortion LCMO Green's function second quantization
4	Untersuchung der elektrischen Phasenseparation in dünnen Manganatschichten mit Rastersondenspektroskopie / Intrinsic phase separation in manganite thin films investigated with scanning tunneling spectroscopy Becker, Thomas 08 June 2004 (has links) No description available. RRW 000 RVC 860 Mathematics and Natural Science Dünne Schichten Einkristall UHV Manganate LCMO LSMO Netzwerkanalyse Rastertunnelmikroskopie Spektroskopie Oberflächenmorphologie Squid Magnetismus Übergang Röntgenreflektivität Thin films single crystalls UHV manganate LCMO LSMO networkanalysis scanning tunneling microscopy spectroscopy surface morphology sqid magnetism transition X-ray reflection 33.05 33.07 33.61 33.64 33.68 33.75 33.79
5	Etude par spectroscopie infrarouge de l'électrodynamique du supraconducteur Pr2-xCexCuO4 et de la manganite La2/3 Ca1/3 Mn03 ZIMMERS, Alexandre 17 September 2004 (has links) (PDF) Nous présentons la dépendance en température de la réponse infrarouge-visible des plans ab de Pr2-xCexCuO4. Dans l'état normal, en variant le dopage de couches minces de x=0.11 (non-supraconductrice) à x=0.17 (supraconductrice surdopée), on observe l'ouverture d'un gap partiel jusqu'au dopage optimal x=0.15. Un modèle d'onde de densité de spin reproduit qualitativement des données. En extrapolant l'amplitude de ce gap, celui-ci s'annule pour x=0.17 indiquant la présence d'un point critique quantique ainsi que la coexistence de magnétisme et de supraconductivité. En dessous de Tc, pour x=0.15 et x=0.17, la modification des spectres optiques à des énergies inférieures à 2Delta=4.7kBTc est interprétée comme la signature de l'ouverture du gap supraconducteur. La réponse optique de La2/3Ca1/3MnO3 mesurée est analysée par un modèle de milieu effectif. L'absorption supplémentaire proche de la transition isolant/métal est interprétée comme la signature d'une percolation dans le système. infrarouge supraconducteur supraconducteur dopé aux électrons Pr2-xCexCuO4 PCCO manganite La2/3Ca1/3MnO3 La0.66Ca0.33MnO3 LCMO conductivité optique onde de densité de spin milieu effectif EMA Bruggeman inhomogénéité couche mince

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