Spontaneous Disorder Near the Mott Transition on Frustrated Lattices
International Centre for Theoretical Sciences via YouTube
Overview
Syllabus
Correlation and Disorder in Classical and Quantum Systems
Spontaneous disorder near the Mott transition on frustrated lattices
Outline
Lattice geometry in the Mott transition..
Frustration?
There are several lattices with triangular motifs in 2D and 3D:
Real material? A snapshot..
The triangular and FCC support LRO, we focus on the pyrochlore..
The pyrochlore Mott transition..
How does the Mott transition occur on the pyrochlore Hubbard model?
Effective model at half filling:
What controls the magnetic state?
The correlated moments couple to the electrons via:
Results: average moment, residual resistivity and phase diagram
Finite temperature: DOS, resistivity..
Experiments, and a more complex model..
Moybdates R2Mo2O7 provide a realisation of pyrochlore Mott physics
Field driven insulator-metal transition in Gd2Mo2O7
What are the key issues?
R2Mo2O7: degrees of freedom Solovyev, 2003
Microscopic model
Simplify
We use the following strategy
"Spontaneous disorder" and its effects..
The qualitative physics:
How do these effects play out? phase diagrams..
Comparing with experiments i phase diagram, magnetisation..
Comparison ii resistivity, optical weight..
Focus on the T=0 state..
Tuning the degree of localisation: the JAF knob..
Thanks
Q&A
Taught by
International Centre for Theoretical Sciences