Siirry päänavigointiin Siirry hakuun Siirry pääsisältöön

Isovalent-substitution effect on the Verwey-type transition in the A-site-ordered double perovskite (Ba,Sr)RFe2O5

  • J. Nakamura
  • , M. Karppinen*
  • , P. Karen
  • , J. Lindén
  • , H. Yamauchi
  • *Tämän työn vastaava kirjoittaja

Tutkimustuotos: LehtiartikkeliArtikkeliTieteellinenvertaisarvioitu

5 Sitaatiot (Scopus)

Abstrakti

Two types of chemical-pressure effects on the Verwey-type transition in BaSmFe2O5 are studied, viz., ionic-size contractions at the Ba and Sm sites. Whereas the replacement of Sm by the smaller Eu and Gd atoms increases the transition temperature TV from 232 K to 264 K, the Sr-for-Ba substitution decreases it from 232 K to 180 K for x=0.15 in (Ba1-xSrx)SmFe2O5. Of various structural parameters determined by synchrotron x-ray diffraction above T V, the magnitude of the orthorhombic distortion (=b-a) is found to correlate with TV in a manner that unifies both substitution schemes. It is suggested that when an increase in b-a above TV is achieved by means of the structural substitution, it makes it easier for the dxz Fe2+ orbital ordering to occur below TV.

AlkuperäiskieliEnglanti
Artikkeli144104
Sivut144104-1-144104-6
JulkaisuPhysical Review B - Condensed Matter and Materials Physics
Vuosikerta70
Numero14
DOI - pysyväislinkit
TilaJulkaistu - lokak. 2004
OKM-julkaisutyyppiA1 Julkaistu artikkeli, soviteltu

Rahoitus

This work was supported by Grants-in-aid for Scientific Research (Nos. 15206002 and 15206071) from the Japan Society for the Promotion of Science. The synchrotron radiation experiments were performed under the auspices of SPring-8 (PRC No. 2002B0170). Professor Satoshi Sasaki and Dr. Ken-ichi Kato and Dr. Kouji Yamawaki are thanked for their experimental guidance.

Sormenjälki

Sukella tutkimusaiheisiin 'Isovalent-substitution effect on the Verwey-type transition in the A-site-ordered double perovskite (Ba,Sr)RFe2O5'. Ne muodostavat yhdessä ainutlaatuisen sormenjäljen.

Viittausmuodot