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Two-dimensional kagome correlations and field induced order in the ferromagnetic XY pyrochlore Yb2Ti2O7
K A Ross1, J P C Ruff, C P Adams
1Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, L8S 4M1, Canada.
Physical Review Letters
|April 7, 2010
Summary
This study reveals that Ytterbium Titanate (Yb2Ti2O7) exhibits quasi-two-dimensional (2D) spin correlations that transition to long-range order (LRO) in a magnetic field, forming a complex phase diagram.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- The Ytterbium Titanate (Yb2Ti2O7) pyrochlore system is known for its complex magnetic properties.
- Understanding the low-temperature magnetic behavior and phase transitions is crucial for exploring exotic quantum states.
Purpose of the Study:
- To investigate the magnetic structure and phase transitions of Yb2Ti2O7 under varying magnetic fields.
- To elucidate the nature of spin correlations and the emergence of long-range order (LRO).
Main Methods:
- Neutron scattering measurements were employed to probe the magnetic correlations.
- Experiments were conducted at low temperatures and under applied magnetic fields.
Main Results:
- Strong quasi-two-dimensional (2D) spin correlations were observed at low temperatures.
- Application of a magnetic field (approx. 0.5 T along [110]) induced a transition to a 3D LRO state.
- Evidence of magnetic decomposition into decoupled kagome planes was found, indicated by scattering rods along 111 directions.
Conclusions:
- Yb2Ti2O7 exhibits a field-induced transition from 2D correlations to 3D long-range order.
- The material displays a complex low-temperature, low-field phase diagram.
- Dispersive spin waves characterize the 3D LRO state.
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