Hall effect and magnetoresistance in single crystals of NdFeAsO$_{1-x}$F$_{x}$

Physics – Condensed Matter – Superconductivity

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

8 pages, 9 figures

Scientific paper

10.1103/PhysRevB.78.134508

Hall effect and magnetoresistance have been measured on single crystals of $NdFeAsO_{1-x}F_{x}$ with x = 0 ($T_c$ = 0 $ $K) and x = 0.18 ($T_c$ = 50 $ $K). For the undoped samples, strong Hall effect and magnetoresistance with strong temperature dependence were found below about 150 K. The magnetoresistance was found to be as large as 30% at 15 K at a magnetic field of 9 T. From the transport data we found that the transition near 155 K was accomplished in two steps: first one occurs at 155 K which may be associated with the structural transition, the second one takes place at about 140 K which may correspond to the spin-density wave like transition. In the superconducting sample with $T_c$ = 50 $ $K, it is found that the Hall coefficient also reveals a strong temperature dependence with a negative sign. But the magnetoresistance becomes very weak and does not satisfy the Kohler's scaling law. These dilemmatic results (strong Hall effect and very weak magnetoresistance) prevent to understand the normal state electric conduction by a simple multi-band model by taking account the electron and hole pockets. Detailed analysis further indicates that the strong temperature dependence of $R_H$ cannot be easily understood with the simple multi-band model either. A picture concerning a suppression to the density of states at the Fermi energy in lowering temperature is more reasonable. A comparison between the Hall coefficient of the undoped sample and the superconducting sample suggests that the doping may remove the nesting condition for the formation of the SDW order, since both samples have very similar temperature dependence above 175 K.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Hall effect and magnetoresistance in single crystals of NdFeAsO$_{1-x}$F$_{x}$ does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Hall effect and magnetoresistance in single crystals of NdFeAsO$_{1-x}$F$_{x}$, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hall effect and magnetoresistance in single crystals of NdFeAsO$_{1-x}$F$_{x}$ will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-175118

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.