Colossal Magnetoresistive Manganites

ISBN-13: 9781402018442 / Angielski / Twarda / 2004 / 447 str.

Tapan Chatterji

Opis

The physics of transition metal oxides has become a central topic of interest to condensed-matter scientists ever since high temperature superconductivity was discovered in hole-doped cuprates with perovskite-like structures. Although the renewed interest in hole-doped perovskite manganites following the discovery of their colossal magnetoresistance (CMR) properties, began in 1993 about a decade after the discovery of high temperature superconductivity, their first investigation started as early as 1950 and basic theoretical ideas were developed during 1951-1960. Experience in sample preparation and characterization, and in growth of single crystals and epitaxial thin films, gained during the research on high temperature superconductors, and the development of theoretical tools, were very efficiently used in research on CMR manganites. In early nineties it appeared to many condensed matter physicists that although the problem of high temperature superconductivity is a difficult one to solve, a quantitative understanding of CMR phenomena might be well within reach. This book is intended to be an account of the latest developments in the phys ics of CMR manganites. When I planned this book back in 2000, I thought that research on the physics of CMR manganites would be more or less consolidated by the time this would be published. I was obviously very optimistic indeed. We are now in 2003 and we still do not have a quantitative understanding of the central CMR effect. Meanwhile the field has expanded. It is still a very active field of research on both the experimental and theoretical fronts."

Spis treści

1 Crystal and Magnetic Structure from Hole to Electron Doped Manganites.- 1 Introduction.- 2 Crystal Structures.- 3 Charge and Orbital Ordering in Manganites.- 4 General Trends From Hole- to Electron-Doped Manganites.- 5 Orbital Frustration for Mn3+-rich Manganites (0 < x < 1/2).- 6 Stability of the CE-type Charge and Orbital Ordering.- 7 Structure and Magnetism in Electron Doped Manganites.- 2 Approach to the metal-insulator transition in manganites.- 1 Introduction.- 2 Structural and Magnetic Phase Diagram of La1-xCaxMnO3, 0 ? x ? 0.22.- 3 Diffuse Scattering.- 4 Spin Dynamics.- 5 General discussion.- 3 The Electronic Structure, Fermi Surface and Pseudogap in Manganites.- 1 Introduction.- 2 Background and Review.- 3 Experimental Technique- Angle-Resolved Photoemission Spectroscopy (ARPES).- 4 Overview of Electronic Structures.- 5 Near Fermi Energy Electronic Structure Probed by High Resolution Angle Resolved Photoemission Spectroscopy (ARPES).- 6 Summary, Conclusion and Outlook.- 4 Multi-scale Phase Modulations in Colossal Magnetoresistance Manganites.- 1 Introduction.- 2 Phasediagramof La1-xCaxMnO3 revisited.- 3 Phase separation in manganites.- 4 High temperature charge-ordering fluctuation and nano-scale phase coexistence.- 5 X-ray scattering studies of high-temperature charge/orbital correlations.- 6 Conclusions.- 7 Acknowledgements.- 5 Theory of Manganites.- 1 Early Theoretical Studies of Manganites.- 2 Model for Manganites.- 3 Spin-Charge-Orbital Ordering.- 4 Phase-separation scenario.- 5 Concluding Remarks.- 6 Orbital effects in manganites.- 1 Introduction.- 2 Orbital order for x < 1/2.- 3 Quantum effects; optimal doping.- 4 Orbital order for x ? 1/2.- 5 Conclusions.- 6 Acknowledgments.- 7 Magnetic excitations of the double exchange model.- 1 Introduction.- 2 Magnetic Excitations for a Simple Double Exchange Model.- 3 More Realistic Models.- 4 Concluding Remarks.- 8 Spin dynamics of bilayer manganites.- 1 Introduction.- 2 Ruddlesden-Popper phases.- 3 Crystal and magnetic structure of bilayer manganites.- 4 Ferromagnetic phase transition in La1.2Sr1.8Mn2O7.- 5 Spin waves in bilayer manganites.- 6 A theory of ferromagnetic spin waves in infinite-layer and bilayer manganites.- 7 Doping dependence of the exchange energies in bilayer manganites..- 8 Diffuse magnetic scattering from La1.2Sr1.8Mn2O7.- 9 Concluding remarks.- 9 Charge and Orbital Ordering of Manganites Observed by Resonant X-ray Scattering.- 1 Introduction.- 2 Principle of Resonant X-ray Scattering to Observe Charge and Orbital Ordering.- 3 Theory of RXS.- 4 Recent development of Resonant X-ray Scattering.- 5 Resonant Inelastic X-ray Scattering to Observe Orbital Excitations.- 6 Summary.- 7 Acknowledgements.- 10 Theory of Manganites Exhibiting Colossal Magnetoresistance.- 1 Introduction.- 2 Coexisting polaronic and band states.- 3 A new model Hamiltonian for manganites in the strong electron lattice JT coupling regime.- 4 DMFT wth polaronic and band states.- 5 Metal insulator transitions.- 6 Resistivity, CMR and material systematics.- 7 Other unusual properties.- 8 Discussion.