The suppression of CMR in Nd(Mn1−xCox)AsO0.95F0.05

E. J. Wildman, K. S. McCombie, G. B. G. Stenning, A. C. McLaughlin* (Corresponding Author)

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)
7 Downloads (Pure)


The colossal magnetoresistance (CMR) observed in the oxypnictide NdMnAsO1−xFx has been further investigated. The magnetotransport is dominated by magnetopolarons. Magnetoresistance measurements of the series Nd(Mn1−xCox)AsO0.95F0.05 show that doping with cobalt on the manganese site pins the magnetopolarons and suppresses the CMR, which is completely destroyed by x = 0.047. The chemical doping results in non-stoichiometric samples, with both As and O vacancies. The relationship between the non-stoichiometry, magnetic order, electron doping and CMR is explored. The Nd antiferromagnetic transition and simultaneous reorientation of the Mn spins into the basal plane at 23 K (TSR) is not effected by Co doping. However, there is a significant decrease in TN(Mn) as the antiferromagnetic transition is suppressed from 360 K to 300 K as x increases from 0–0.047. The manganese moment at 10 K is also reduced from 3.86(2)μB to 3.21(2)μB over the same doping range. This reduction in the in-plane Mn moment decreases the electron–electron correlations below TSR and acts to further diminish the magnetoresistance.
Original languageEnglish
Pages (from-to)14726-14733
Number of pages8
JournalDalton Transactions
Issue number41
Early online date28 Sept 2018
Publication statusPublished - 7 Nov 2018

Bibliographical note

This research is supported by the EPSRC (research grant EP/L002493/1). We also acknowledge the UK Science and Technology Facilities Council (STFC) for provision of beam time at ISIS.


Dive into the research topics of 'The suppression of CMR in Nd(Mn1−xCox)AsO0.95F0.05'. Together they form a unique fingerprint.

Cite this