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Anisotropy of electron momentum distribution in Bi$_2$Sr$_2$CaCu$_2$O$_(8+d)$ superconductor studied by positron annihilation technique

Mahuya Chakrabarti·A. Sarkar·S. Chattapadhayay·D. Sanyal·A. K. Pradhan·R. Bhattacharya·D. Banerjee
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Abstract

The temperature dependent (30 K to 300 K) Doppler broadening of the positron annihilated g-radiation (DBPAR) measurement has been carried out on single crystalline Bi-2212 high Tc superconducting sample along two different crystallographic orientations. It has been observed that throughout the temperature range the electron momentum distribution has a relatively large value along the crystallographic c-axis than a-b plane. The temperature dependent DBPARL analysis shows a step like increase of S-parameter at the temperature region 92 K to 116 K.

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Mahuya Chakrabarti, A. Sarkar, S. Chattapadhayay, D. Sanyal, A. K. Pradhan, R. Bhattacharya, D. Banerjee. 2003-07-30. Anisotropy of electron momentum distribution in Bi$_2$Sr$_2$CaCu$_2$O$_(8+d)$ superconductor studied by positron annihilation technique. https://doi.org/10.1016/j.ssc.2003.07.007

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