论文标题
多门电荷密度波动激发和伴随的声子异常在BI $ _2 $ _2 $ sr $ _2 $ lacuo $ _ {6+δ} $
Multi-orbital charge density wave excitations and concomitant phonon anomalies in Bi$_2$Sr$_2$LaCuO$_{6+δ}$
论文作者
论文摘要
电荷密度波（CDW）在掺杂的铜酸盐超导体中无处不在。作为价电子密度的调节，由于这些轨道在费米水平附近的强杂交，孔掺杂的库酸酯中的CDW具有CU-3D和O-2P轨道特性。在这里，我们调查了不足的bi $ _2 $ sr $ _ {1.4} $ la $ _ {0.6} $ cuO $ _ {6+δ} $，使用谐振X射线散射（RIX），并在CU和O cu cu cuboxiention（cu cuo cuo cuo cuo cuo cuo cuo cuo2）中都存在短距离CDW（rixs），并发现了cuo2-cuo2-cuo2-cuo2-2）。此外，我们发现了与CDW伴随的键伸展和键曲曲子的声子异常。比较略微过度掺杂的bi $ _2 $ sr $ _ {1.8} $ la $ _ {0.2} $ cuo $ _ {6+δ} $，在CDWS和声子异常中都不会出现，我们强调，在CDW Waveecter（QCCD）的距离（QCCD）的附近中，急剧强度异常（QCCD）与QCCD的距在波录机处的键拉伸声子的增强远大于QCDW。我们的结果提供了准静态CDW，它们的分散激发以及相关的电子呼应的全面图片，这是了解库酸酯中竞争的电子不稳定性的关键。
Charge density waves (CDWs) are ubiquitous in under-doped cuprate superconductors. As a modulation of the valence electron density, CDWs in hole-doped cuprates possess both Cu-3d and O-2p orbital character owing to the strong hybridization of these orbitals near the Fermi level. Here, we investigate under-doped Bi$_2$Sr$_{1.4}$La$_{0.6}$CuO$_{6+δ}$ using resonant inelastic X-ray scattering (RIXS) and find that a short-range CDW exists at both Cu and O sublattices in the copper-oxide (CuO2) planes with a comparable periodicity and correlation length. Furthermore, we uncover bond-stretching and bond-buckling phonon anomalies concomitant to the CDWs. Comparing to slightly over-doped Bi$_2$Sr$_{1.8}$La$_{0.2}$CuO$_{6+δ}$, where neither CDWs nor phonon anomalies appear, we highlight that a sharp intensity anomaly is induced in the proximity of the CDW wavevector (QCDW) for the bond-buckling phonon, in concert with the diffused intensity enhancement of the bond-stretching phonon at wavevectors much greater than QCDW. Our results provide a comprehensive picture of the quasi-static CDWs, their dispersive excitations, and associated electron-phonon anomalies, which are key for understanding the competing electronic instabilities in cuprates.
