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Specific heat jump of superconducting crystal in low temperature

저온에서 초전도 결정의 비열 점프

  • Kim, Cheol-Ho (Department of Electronic and Optical Engineering, Honam Univ.)
  • 김철호 (호남대학교 전자광공학과)
  • Received : 2010.11.03
  • Accepted : 2011.01.21
  • Published : 2011.02.28

Abstract

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.

본 논문에서는 먼저 저온에서의 초전도 결정의 비열 점프를 임계 온도의 함수로 구하였다. 다음에, 구한 비열 점프의 부호와 크기 등을 분석하여 여러 가지 실험적인 사실들을 예측하였다. 마지막으로 우리가 예측한 실험 사실과 실제의 실험이 일치하는지 비교하였다. 이론적으로 구한 비열점프는 $YNi_2B_2C$ 결정의 비열 점프 업 과 비열 점프 다운 현상을 비교적 잘 설명한다. 특히 매우 낮은 온도에서는 상전도-초전도 전이 시에 비열이 점프 다운된다는 주목할 만한 이론적 예측을 실험 결과를 통해 확인할 수 있었다.

Keywords

Acknowledgement

Supported by : 호남대학교

References

  1. H. Hiraki and Y. Endoh, "Field dependence of magnetic phase transition in metallic ferromagnet-specific heat measurements-", J. Phys. Soc. Jpn. 68 (1999) 36. https://doi.org/10.1143/JPSJ.68.36
  2. C.P. Sun, J.Y. Lin, S. Mollah, P.L. Ho, D.H. Yang, F.C. Hsu, Y.C. Liao and M.K. Wu, "Magnetic field dependence of low-temperature specific heat of the spinel oxide superconductor $LiT_2O_4$", Phys. Rev. B 70 (2004) 054519. https://doi.org/10.1103/PhysRevB.70.054519
  3. J.H. Choi, H. Doh, E.M. Choi, H.J. Kim, S.I. Lee, T. Yamamoto, T. Kawae and K. Takeda, "Specific Heat of field-dependent magnetic orderings in TEX>$HoNi_2B_2,C$", J.Phys. Soc. Jpn. 70 (2001) 3037. https://doi.org/10.1143/JPSJ.70.3037
  4. K. Machida and M. Ichioka, "Magnetic field dependence of low-temperature specific heat in $SR_2RuO_4$", Phys. Rev. B 77 (2008) 184515. https://doi.org/10.1103/PhysRevB.77.184515
  5. J. Baak, H.B. Brom, M.J.V. Menken and A.A. Menovsky, "The low temperature specific heat in single crystals of $Ba_2Cu_3O_7$", Physica C 162-164 (1989) 500. https://doi.org/10.1016/0921-4534(89)91125-8
  6. A.C. Rose-Innes and E.H. Rhoderick, Introduction to Superconductivity, 2nd ed. (Pergamon Press, New York,1978) Chap. 4-5.
  7. M. Tinkham, Introduction to Superconductivity (Pergamon McGraw-Hill, New York, 1975) Chap. 2.
  8. T. Sakudo, Solid State Physics: Magnetism and Superconductivity, 1st ed. (Shokabo, Tokyo, 1993) Chap. 6.
  9. N. Michoshiba and K.Suzuki, Introduction to Physics of Superconductivity, 1st ed. (Baifukan, Tokyo, 1995) Chap. 1.
  10. M. Yamamura, Superconductor Engineering, 5th ed. (Denkigakkai, Tokyo, 1994) Chap. 1.
  11. C.L. Huang, J.Y. Lin. C.P. Sun, T.K. Lee, J.D. Kim, E.M. Choi, S.I. Lee and H.D. Yang, "Comparative analysis of M. Choi, S. I. $LYNi_2B_2C $ using nodal and twogap models", Phy. Rev. B 73 (2006) 012502.