Electronic nematic states and stripe order in cuprate high-Tc superconductors investigated by STM/STS

2016 Fiscal Year Final Research Report

• Project/Area Number: 26400343
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Condensed matter physics II
• Research Institution: Muroran Institute of Technology
• Principal Investigator: MOMONO Naoki 室蘭工業大学, 工学研究科, 教授 (00261280)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 銅酸化物高温超伝導体 / 走査トンネル顕微鏡 / ストライプオーダー / 電子ネマティック状態

Outline of Final Research Achievements

In STM experiments on Fe-doped Bi2212, two kinds of 2-dimensional(2D) modulation were observed in STM images; one shows 5a by 5a modulation and the other shows 4a by 4a modulation, where a is lattice constant within Cu-O layer. The latter can be ascribed to the pinning due to Fe impurities. In Dy-doped Bi2212, the superconducting transition temperature Tc is largely suppressed around the hole concentration p=1/8. The 2D modulation of the STM image for p=1/8 shows 3.3a by 3.3a period. It will be difficult to explain these periodicities of the 2D modulations by some kind of the Fermi surface nesting. In Dy-doped Bi2212, the 4-fold rotational symmetry of the 2D modulation in STM images is broken regardless of the STM tip and scanning direction, indicating that the 2D modulation for p=1/8 is consistent with some kind of the nematic states of the electrons.

Free Research Field

固体物理