High-pressure flux growth, structural, and superconducting properties of LnFeAsO (Ln = Pr, Nd, Sm) single crystals
METADATA ONLY
Loading...
Author / Producer
Date
2012-12
Publication Type
Journal Article
ETH Bibliography
yes
METADATA ONLY
Data
Rights / License
Abstract
Single crystals of the LnFeAsO (Ln1111, Ln = Pr, Nd, and Sm) family with lateral dimensions up to 1 mm were grown from NaAs and KAs flux at high pressure. The crystals are of good structural quality and become superconducting when O is partially substituted by F (PrFeAsO1-xFx and NdFeAsO1-xFx) or when Fe is substituted by Co (SmFe 1-xCoxAsO). From magnetization measurements, we estimate the temperature dependence and anisotropy of the upper critical field and the critical current density of underdoped PrFeAsO0.7F0.3 crystal with Tc ≈ 25 K. Single crystals of SmFe 1-xCoxAsO with maximal Tc up to 16.3 K for x ≈ 0.08 were grown. From transport and magnetic measurements, we estimate the critical fields and their anisotropy and find these superconducting properties to be quite comparable to the ones in SmFeAsO1-xFx with a much higher Tc ≈ 50 K. The magnetically measured critical current densities are as high as 109 A/m2 at 2 K up to 7 T, with indication of the usual fishtail effect. The upper critical field estimated from resistivity measurements is anisotropic with slopes of ∼-8.7 T/K (H||ab plane) and ∼-1.7 T/K (H||c axis). This anisotropy (∼5) is similar to that in other Ln1111 crystals with various higher Tc's.
Permanent link
Publication status
published
External links
Editor
Book title
Journal / series
Volume
86 (21)
Pages / Article No.
214509
Publisher
American Physical Society
Event
Edition / version
Methods
Software
Geographic location
Date collected
Date created
Subject
Organisational unit
03569 - Batlogg, Bertram (emeritus)