Experimental evidence of two-band behavior of MgB2

Ya. G. Ponomarev; S. A. Kuzmichev; M. G. Mikheev; M. V. Sudakova; S. N. Tchesnokov; N. Z. Timergaleev; A. V. Yarigin; E. G. Maksimov; S. I. Krasnosvobodtsev; A. V. Varlashkin; M. A. Hein; G. Muller; H. Piel; L. G. Sevastyanova; O. V. Kravchenko; K. P. Burdina; B. M. Bulychev

doi:10.1016/j.ssc.2003.09.024

arXiv · cond-mat/0303640

Experimental evidence of two-band behavior of MgB2

Ya. G. Ponomarev·S. A. Kuzmichev·M. G. Mikheev·M. V. Sudakova·S. N. Tchesnokov·N. Z. Timergaleev·A. V. Yarigin·E. G. Maksimov·S. I. Krasnosvobodtsev·A. V. Varlashkin·M. A. Hein·G. Muller·H. Piel·L. G. Sevastyanova·O. V. Kravchenko·K. P. Burdina·B. M. Bulychev

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Abstract

The break-junction tunneling has been systematically investigated in MgB2. Two types of the break-junction contacts have been exploited on the same samples, which demonstrated tunnel contact like (SIS) and point contact like (SnS) behavior. Both of them have shown the existence of the two distinct energy gaps. We have observed also the peculiarities on the I(V)- characteristics related to Leggett's collective mode assisted tunneling. --> Corresponding author address: kuzmichev@mig.phys.msu.ru

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Ya. G. Ponomarev, S. A. Kuzmichev, M. G. Mikheev, M. V. Sudakova, S. N. Tchesnokov, N. Z. Timergaleev, A. V. Yarigin, E. G. Maksimov, S. I. Krasnosvobodtsev, A. V. Varlashkin, M. A. Hein, G. Muller, H. Piel, L. G. Sevastyanova, O. V. Kravchenko, K. P. Burdina, B. M. Bulychev. 2003-06-24. Experimental evidence of two-band behavior of MgB2. https://doi.org/10.1016/j.ssc.2003.09.024

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