Effect of magnetic impurities on the vortex lattice properties in NbSe{sub 2} single crystals.
We report a pronounced peak effect in the magnetization of Co{sub x}NbSe{sub 2} single crystals with critical temperatures T{sub c} ranging between 7.1 and 5.0 K, and Mn{sub x}NbSe{sub 2} single crystals with critical temperatures down to 3.4 K. We correlate the peak effect in magnetization with the structure of the vortex lattice across the peak-effect region using scanning-tunneling microscopy. Magnetization measurements show that the amplitude of the peak effect in the case of Co{sub x}NbSe{sub 2} exhibits a nonmonotonic behavior as a function of the Co content, reaching a maximum for concentration of Co of about 0.4 at. % (corresponding to a T{sub c} of 5.7 K) and after that gradually decreasing in amplitude with the increase in the Co content. The normalized value of the peak position H{sub p}/H{sub c2} has weak dependence on Co concentration. In the case of Mn{sub x}NbSe{sub 2} the features of the peak effect as a function of the Mn content are different and they can be understood in terms of strong pinning.
- Research Organization:
- Argonne National Laboratory (ANL)
- Sponsoring Organization:
- SC; NSF; CNR; IFCAM
- DOE Contract Number:
- AC02-06CH11357
- OSTI ID:
- 960351
- Report Number(s):
- ANL/MSD/JA-62420
- Journal Information:
- Phys. Rev. B, Journal Name: Phys. Rev. B Journal Issue: Nov. 2008 Vol. 78; ISSN 1098-0121
- Country of Publication:
- United States
- Language:
- ENGLISH
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