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06:49
Radio Frequency Magnetron Sputtering of GdBa2Cu3O7−δ/ La0.67Sr0.33MnO3 Quasi-bilayer Films on SrTiO3 (STO) Single-crystal Substrates
Published on: April 12, 2019
Fragile magnetic ground state in half-doped LaSr2Mn2O7
1Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA. jslee@slac.stanford.edu
Physical Review Letters
|August 16, 2011
Summary
We studied orbital and magnetic ordering in bilayer manganites using resonant soft x-ray scattering. CE-type orbital order was observed, coexisting with coupled CE- and A-type antiferromagnetic orders.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Magnetism
Background:
- Bilayer manganites exhibit complex electronic and magnetic properties.
- Understanding orbital and magnetic ordering is crucial for their applications.
Purpose of the Study:
- To investigate the orbital and antiferromagnetic ordering behaviors in La(2-2x)Sr(1+2x)Mn2O7 (x ≃ 0.5).
- To elucidate the relationship between orbital order and magnetic orders.
Main Methods:
- Mn L(2,3)-edge resonant soft x-ray scattering was employed.
- Analysis of scattering patterns to determine orbital and magnetic structures.
Main Results:
- CE-type orbital order was observed below T(oo) ≃ 220 K, with partial melting below T(m) ≃ 165 K.
- Coexistence of CE- and A-type antiferromagnetic orders was found.
- Both magnetic orders are coupled with the CE-type orbital order.
Conclusions:
- The ground state with CE-type antiferromagnetic order is sensitive to doping fluctuations.
- Small doping variations can destabilize the CE-type order into the A-type one.
- Narrow magnetic phase boundaries at x ≃ 0.5±0.005 support this sensitivity.
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