English

Electric field gradients in MgB$_2$ synthesized at high pressure: $^111$Cd TDPAC study and ab initio calculation

Materials Science 2009-11-07 v1 Superconductivity

Abstract

We report the high-pressure synthesis of novel superconductor MgB2_2 and some related compounds. The superconducting transition temperature of our samples of MgB2_2 is equal to 36.6 K. The MgB2_2 lattice parameters determined via X-ray diffraction are in excellent agreement with results of our ab initio calculations. The time-differential perturbed angular correlation (TDPAC) experiments demonstrate a small increase in quadrupole frequency of 111^111Cd probe with decreasing temperature from 293 to 4.2 K. The electric field gradient (EFG) at the B site calculated from first principles is in fair agreement with EFG obtained from 11^11B NMR spectra of MgB2_2 reported in the literature. It is also very close to EFG found in our 111^111Cd TDPAC measurements, which suggests that the 111^111Cd probe substitutes for boron in the MgB2_2 lattice.

Keywords

Cite

@article{arxiv.cond-mat/0104560,
  title  = {Electric field gradients in MgB$_2$ synthesized at high pressure: $^111$Cd TDPAC study and ab initio calculation},
  author = {A. V. Tsvyashchenko and L. N. Fomicheva and M. V. Magnitskaya and E. N. Shirani and V. B. Brudanin and D. V. Filossofov and O. I. Kochetov and N. A. Lebedev and A. F. Novgorodov and A. V. Salamatin and N. A. Korolev and A. I. Velichkov and V. V. Timkin and A. P. Menushenkov and A. V. Kuznetsov and V. M. Shabanov and Z. Z. Akselrod},
  journal= {arXiv preprint arXiv:cond-mat/0104560},
  year   = {2009}
}

Comments

10 pages, 3 figures