Sains Malaysiana 34(2): 73-76 (2005)
Mod Fonon dan Gandingan Elektron-Fonon untuk
Kesuperkonduksian dalam Kuprat Dua Dimensi
(Phonon Mode and Electron-Phonon Coupling for Superconductivity
in Two-Dimensional Cuprates)
Roslan Abd Shukor
Pusat Pengajian Fizik Gunaan
Fakulti Sains dan Teknologi
Universiti Kebangsaan Malaysia 43650 UKM Bangi
Selangor, D.E. Malaysia
ABSTRAK
Pemalar gandingan elektron-fonon dalam superkonduktor suhu tinggi berasaskan kuprum oksida telah diukur melalui Kaedah akustik. Hubungan terus antara pemalar gandingan elektron-fonon sistem dua dimensi senario van Hove, lvH dengan suhu genting telah dicerap. Suhu cirian Debye bagaimana pun tidak berkorelasi dengan suhu genting. Keputusan ini menunjukkanfrekuensi Debye dan gandingan elektron-fonon dalam sistem dua dimensi saling mempengaruhi dan mempunyai kesan dalam menentukan suhu genting. Pemalar gandingan van Hove adalah dalam julat lvH = 0.025 – 0.060 konsisten dengan pembentukan pasangan Cooper oleh interaksi elektronfonon bagi mod pernafasan oksigen tak diagonal dalam satah Cu02.
Katakunci: Gandingan elektron-fonon, suhu Debye, senario van Hove, mod pernafasan
ABSTRACT
The electron-phonon coupling constant in the cup rate high temperature superconductors has been determined by the acoustic method. A proportional relation between the electron-phonon coupling constant for a two dimensional system in the van Hove scenario, lvH and the transition temperature is observed. The characteristic Debye temperature, however does not correlate with the transition temperature. Our results show the importance of interplay between the Debye frequency and electron-phonon coupling in the two dimensional system and their variations have combined effect in governing the transition temperature. The van Hove electron-phonon coupling constant is in the range of lvH = 0.025 – 0.060 consistent with Cooper pairs formation by non-diagonal electron-phonon interaction of the in-plane oxygen breathing mode in the CuO2 plane. .
Keyword: Electron-phonon coupling-debye temperature, van scenario, breathing mode.
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