Neutron Scattering Studies on the High-T_c Superconductor La_3Ni_2O_7-δ at Ambient Pressure
arxiv(2024)
摘要
After several decades of studies of high-temperature superconductivity, there
is no compelling theory for the mechanism yet; however, the spin fluctuations
have been widely believed to play a crucial role in forming the superconducting
Cooper pairs. The recent discovery of high-temperature superconductivity near
80 K in the bilayer nickelate La_3Ni_2O_7 under pressure provides a new
platform to elucidate the origins of high-temperature superconductivity. We
perform elastic and inelastic neutron scattering studies on a polycrystalline
sample of La_3Ni_2O_7-δ at ambient pressure. No magnetic order can
be identified down to 10 K. However, we observe a weak flat spin-fluctuation
signal at ∼ 45 meV in the inelastic scattering spectra. The observed spin
excitations could be interpreted as a result of strong interlayer and weak
intralayer magnetic couplings for a double-stripe antiferromagnetic order. The
absence of long-range magnetic order in neutron diffraction measurements may be
ascribed to a short-range magnetic correlation length perpendicular to the
stripe direction. Our results provide crucial information on the spin dynamics
and are thus important for understanding the superconductivity in
La_3Ni_2O_7.
更多查看译文
AI 理解论文
溯源树
样例
生成溯源树,研究论文发展脉络
Chat Paper
正在生成论文摘要