New oxypnictide superconductors: PrOFe{sub 1-x}Co{sub x}As

Journal Article · Mon Feb 15 00:00:00 EST 2010 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.11.026· OSTI ID:21372487

Prakash, J ^[1]; Singh, S J ^[2]; Das, D ^[3]; Patnaik, S ^[2]

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1. Department of Chemistry, Indian Institute of Technology, New Delhi 110016 (India)
2. School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067 (India)
3. UGC-DAE Consortium for Scientific Research, Kolkata 700098 (India)

Oxypnictides of the type PrOFe{sub 1-x}Co{sub x}As (x<=0.3) were synthesized for the first time by the sealed tube method. All the compounds were found to be monophasic and crystallize in the tetragonal ZrCuSiAs type structure (space group=P4/nmm) and the lattice parameters (a and c) decrease with increase in cobalt content. Moessbauer measurements of the compounds indicate low spin Fe{sup 2+} in tetrahedral coordination. Resistivity and magnetization studies reveal superconducting transitions in compounds with 'x'=0.05, 0.10 and 0.15, with maximum transition temperature (T{sub c}) at {approx}14 K in the compound with 'x'=0.1. The variation of resistivity with temperature under different magnetic field has been studied to estimate the upper critical field (H{sub c2}) ({approx}50.2 T for the 'x'=0.1 composition). The Seebeck and Hall coefficient (R{sub H}) suggests electron type charge carriers in these compound and the charge carrier density increases with increase in Co-doping. - Graphical abstract: Cobalt doping at the iron site in PrOFeAs (semimetal) compound suppresses structural distortion and spin density wave with the evolution of superconductivity. The Seebeck and Hall coefficient (R{sub H}) indicate electron type charge carriers in these compounds and charge carrier density increases with increase in Co-doping. Temperature dependence of resistivity (rho) for (a) PrOFeAs, (b) PrOFe{sub 0.95}Co{sub 0.05}As, (c) PrOFe{sub 0.9}Co{sub 0.1}As, (d) PrOFe{sub 0.85}Co{sub 0.15}As, (e) PrOFe{sub 0.8}Co{sub 0.2}As and (f) PrOFe{sub 0.7}Co{sub 0.3}As.

• OSTI ID: 21372487
• Journal Information: Journal of Solid State Chemistry, Vol. 183, Issue 2; Other Information: DOI: 10.1016/j.jssc.2009.11.026; PII: S0022-4596(09)00555-6; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ARSENIDES
CHARGE CARRIERS
COBALT COMPOUNDS
HALL EFFECT
IRON COMPOUNDS
IRON IONS
LATTICE PARAMETERS
MAGNETIZATION
MOESSBAUER EFFECT
OXYGEN COMPOUNDS
PRASEODYMIUM COMPOUNDS
SPACE GROUPS
SUPERCONDUCTIVITY
SUPERCONDUCTORS
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0013-0065 K
TETRAGONAL LATTICES
TRANSITION TEMPERATURE
ARSENIC COMPOUNDS
CHARGED PARTICLES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
IONS
PHYSICAL PROPERTIES
PNICTIDES
RARE EARTH COMPOUNDS
SYMMETRY GROUPS
TEMPERATURE RANGE
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS