• Title/Summary/Keyword: $YNi_2B_2C$ superconductor

Search Result 5, Processing Time 0.028 seconds

The upper critical field (($H_{c2}$) study of intermetallic $YNi_{2}$$B_{2}$C superconductor (중간금속성 $YNi_{2}$$B_{2}$C 초전도체의 상부임계자기장($H_{c2}$) 연구)

  • Song, K.J.;Lee, N.J.;Ko, R.K.;Park, C;Ha, H.S.;Ha, D.W.;Oh, S.S.;Kwon, Y.K
    • Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
    • /
    • 2002.02a
    • /
    • pp.168-170
    • /
    • 2002
  • Magnetization studies were conducted on a single crystal of $YNi_{2}$$B_{2}$C superconductor. The 17 mg crystal was studied at temperatures T from above $T_{c}$ (15.5 K) to 3 K, in the magnetic fields H // c-axis up to 6 tesla. The crystal exhibited little magnetic irreversibility, with a critical current density $CO_{3}$ ~ $10^{-4}$ $\times$ $CO_{3}$, the depairing current density. Near $T_{c}$, the equilibrium magnetization M was London-like with M $\infty$ In(H). The upper critical field $H_{c2}$ of the single crystal $YNi_{2}$$B_{2}$C was estimated by the several alternative approaches such as standard London limit, Ginzburg-Landau, and Abrikosov relations. The estimated $H_{c2}$values agree relatively well with each other approaches.

  • PDF

Local Field Distribution in YNi$_2B_2C$ Superconductor (YNi$_2B_2C$의 초전도 상태에서 국소자기장의 분포)

  • Kim, Do-Hyeong;Lee, Kyu-Ho;Han, Ki-Seong;Seo, Seung-Won;Lee, Moo-Hee;Lee, Seong-Ik;Cho, Byeong-Ki
    • 한국초전도학회:학술대회논문집
    • /
    • v.9
    • /
    • pp.251-255
    • /
    • 1999
  • Local field distribution in the mixed state of type II superconductors has been numerically calculated and compared with $^{11}$B NMR spectra for YNi$_2B_2C$ single crystals. We find that only small distortion of vortex positions from the perfect lattice points is enough to smear out the low frequency shoulder. As the vortices are further distorted, the line shape changes from an asymmetric shape with a high frequency tail to a symmetric Gaussian line shape. It is found that the second moment of the field distribution has a major contribution from the high frequency tail. Consequently, a linewidth of the full width at half maximum calculated from the second moment assuming for a Gaussian line shape is overestimated.

  • PDF

Specific heat jump of superconducting crystal in low temperature (저온에서 초전도 결정의 비열 점프)

  • Kim, Cheol-Ho
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.21 no.1
    • /
    • pp.1-5
    • /
    • 2011
  • In this paper, firstly we have derived and presented the specific heat jump as a function of the critical temperature. Secondly, we have analyzed the sign and magnitude of the derived specific heat jump and predicted the expected experimental results. And lastly, we have compared the expected experimental results with the real experimental results. Theoretically derived specific heat jump is considerably compatible with the specific heat jump up and down phenomena of the $YNi_2B_2C$ crystal. Especially, the remarkable theoretical prediction-hat the specific heat would jump down during the normal state-to-superconducting state transition at extremely low temperatures-have been confirmed by the experimental results.