Tunneling spectrum analysis regarding phonon contribution to high T{sub c} Cooper pairing

Journal Article · Sun Dec 01 04:00:00 EST 1996 · Journal of Low Temperature Physics

DOI:https://doi.org/10.1007/BF00753868· OSTI ID:443651

Aoki, Ryozo; Murakami, Hironaru ^[1]

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1. Osaka Univ., Suita (Japan)

Improved tunneling spectroscopy with point contact junction of [BSCCO(2212)/SiO{sub x}]/Au-tip provided the authors information of the quasi-particle that mediates the high T{sub c} Cooper pairing. Fine structure in the tunneling conductance derivative spectrum d{sup 2}I/dV{sup 2} - V reflects the quasi particle coupling spectrum function {alpha}{sup 2}({omega})F({omega}), and really significant peaks have been observed ranging to 0.2 eV. Their peak energy level eV{sub i} could be systematically assigned by eV{sub i} - {Delta} = n{epsilon}{sub 0} + {h_bar}{omega}{sub i}(ph) with n=0, 1, 2. Here {h_bar}{omega}{sub i} means each phonon mode energy, and the characteristic energy {epsilon}{sub 0} = 72 meV was found to correspond to the breathing mode which is essentially Cu-O bond stretching mode. This means that these characteristic phonons play a significant role on the high T{sub c} superconductivity. Similar peak series had been also observed in the infrared (IR) optical reflection spectrum R({omega}) by Capizzi et al. The Cooper pairing characteristics are discussed from the comparison between both spectra of the tunneling and the IR.

• Sponsoring Organization: USDOE
• OSTI ID: 443651
• Report Number(s): CONF-960808--
• Journal Information: Journal of Low Temperature Physics, Journal Name: Journal of Low Temperature Physics Journal Issue: 5-6 Vol. 105; ISSN 0022-2291; ISSN JLTPAC
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BISMUTH OXIDES
CALCIUM OXIDES
COOPER PAIRS
COPPER OXIDES
HIGH-TC SUPERCONDUCTORS
QUASI PARTICLES
STRONTIUM OXIDES
TUNNEL EFFECT