151Eu Mössbauer and magnetic studies on magnetic superconductor

✍ Scribed by Rakesh Kumar; C.V. Tomy; P.L. Paulose; R. Nagarajan

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 148 KB
• Volume: 378-380
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2006.01.141

✦ Synopsis

Magnetic and 151 Eu Mo¨ssbauer studies have been carried out on the ruthenocuprate magnetic superconductors, EuSr 2 Ru 1Àx Cu 2þx O 8 ðÀ0:1pxp0:25Þ. The magnetic ordering temperature (T M ) decreases from 135 K for x ¼ 0:0 to 125 K for x ¼ 0:25 and the superconducting transition temperature increases from 19 K (onset for x ¼ 0:0) to 33 K (x ¼ 0:1). The compounds with xo0 do not show superconductivity down to 2 K but show an increase in T M . The 151 Eu Mo¨ssbauer studies show that the Eu ions are in 3+ (4f 6 ; J ¼ 0) and hence in the nonmagnetic state in these compounds. The observation of a broadening in the 151 Eu Mo¨ssbauer absorption spectra below the magnetic ordering temperature indicates a small transferred magnetic hyperfine field at the Eu site.