Imaging stripe dynamics in trilayer nickelate La₄Ni₃O₁₀

摘要

该研究利用自旋极化扫描隧道显微镜对三层镍酸盐La₄Ni₃O₁₀中的条纹序进行了实空间成像，揭示了其局域磁性和电荷分布。实验发现，该条纹序具有四倍单胞的周期性，与铜氧化物高温超导体中的条纹序高度相似，并在费米能级附近打开了一个约66 meV的近完全能隙。更重要的是，当隧穿电子能量超过约20 meV的阈值时，可以触发离散的相位滑移，从而实现了原子尺度上的条纹动力学成像。这些结果强调了关联物理在驱动镧镍酸盐中类似条纹序中的关键作用，并显示出其与铜氧化物超导体惊人的相似性，为理解镍基超导体的配对机制提供了重要线索。

材料

• La₄Ni₃O₁₀

方法

• spin-polarized STM
• scanning tunneling spectroscopy

关键词

• stripe order
• charge density wave
• magnetic order
• phase slips

亮点

• First real-space imaging of stripe dynamics at atomic scale using spin-polarized STM.
• Stripe order exhibits spontaneous phase jumps induced by tunneling electrons above a threshold energy.
• Demonstrates striking similarities between nickelate and cuprate stripe orders, supporting a common correlation-driven mechanism.

结论

• Real-space imaging reveals stripe order with four-unit-cell periodicity in La₄Ni₃O₁₀, closely resembling cuprate stripe orders.
• The stripe order consists of intertwined magnetic and charge orders, with antiphase antiferromagnetic domains separated by electron-rich rivers.
• Tunneling electrons above 20 meV can trigger discrete phase slips, enabling atomic-scale imaging of stripe dynamics.
• The near-complete 66 meV gap at the Fermi level and the magnetic wave vectors are consistent with correlation-driven stripe order rather than pure nesting.

主要论断

• Stripe order in La₄Ni₃O₁₀ exhibits four-unit-cell periodicity and a ≈66 meV gap
  • 证据: From abstract: 'stripe order exhibits a four unit cell periodicity, closely resembling that seen in cuprates, and opens a near-complete ≈66meV gap at the Fermi level'
• Discrete phase slips can be triggered by tunneling electrons above ≈20 meV threshold
  • 证据: From abstract: 'discrete phase slips can be triggered by tunneling electrons above a ≈20 meV threshold, allowing imaging of stripe dynamics at the atomic scale'
• Magnetic order accompanies charge stripe, consisting of antiphase antiferromagnetic domains
  • 证据: From text: 'We find antiphase antiferromagnetic domains separated by quasi-1D electron-rich rivers'

研究流程

• single_crystal_growth — High-quality single crystals synthesized
  • 材料: La₂O₃; NiO
  • 方法: optical floating zone growth; high-pressure oxygen annealing
  • 观察: single crystal of La₄Ni₃O₁₀
• scanning_tunneling_microscopy_measurements — Stripe order imaged with four-unit-cell periodicity and ≈66 meV gap
  • 材料: La₄Ni₃O₁₀ single crystal
  • 方法: spin-polarized STM; non-magnetic STM
  • 观察: charge stripe modulation; magnetic contrast; tunneling spectra
• data_analysis — Stripe order consists of antiphase antiferromagnetic domains separated by electron-rich rivers
  • 材料: STM images and spectra
  • 方法: Fourier analysis; fugacity analysis
  • 观察: charge and magnetic order wave vectors; electron doping map