Interplay between magnetism and sodium vacancy ordering in NaxCoO2

Abstract

Using a combination of low-temperature nanocalorimetry and x-ray diffraction we identify three temperature regimes characterized by distinct Na ordering patterns (low temperature up to 290 K, intermediate 290-340 K, and high above 340 K). Through freezing-in of these patterns we establish the two key roles sodium intercalation plays in the formation of the magnetic ground state: supplying the proper electron count for in-plane ferromagnetic interaction and through the 3D sodium ordering providing the interplane antiferromagnetic exchange path.

References in corpus (5)

• Crystal Structure and Elementary Properties of NaxCoO2 (x = 0.32, 0.5, 0.6, 0.75, and 0.92) in the Three-Layer NaCoO2 Family
• Electronic phase diagram of the layered cobalt oxide system, LixCoO2 (0.0 <= x <= 1.0)
• Direct link between low temperature magnetism and high temperature sodium order in NaxCoO2
• Precise Control of Band Filling in NaxCoO2
• Crystal-to-stripe reordering of sodium ions in NaxCoO2 (x>=0.75)

Cited by in corpus (2)

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