The normal state of optimally doped cuprates is dominated by the “strange metal” phase that shows a linear temperature (T) dependence of the resistivity persisting down to the lowest T. For underdoped cuprates, this behavior is lost below the pseudogap temperature T*, where charge density waves (CDWs), together with other intertwined local orders, characterize the ground state. We found that the T-linear resistivity of highly strained, ultrathin, underdoped YBa₂Cu₃O_7–δ films is restored when the CDW amplitude, detected by resonant inelastic x-ray scattering, is suppressed. This observation suggests an intimate connection between the onset of CDWs and the departure from T-linear resistivity in underdoped cuprates. Our results illustrate the potential of using strain control to manipulate the ground state of quantum materials.

中文翻译：

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通过抑制欠掺杂 YBa2Cu3O7-δ 中的电荷密度波恢复奇异金属相

最佳掺杂铜酸盐的正常状态由“奇异金属”相支配，该相显示出电阻率的线性温度 ( T ) 依赖性持续到最低T。对于欠掺杂铜酸盐，这种行为在低于赝能隙温度T * 时消失，其中电荷密度波（CDW）与其他相互交织的局部顺序一起表征基态。我们发现高应变、超薄、欠掺杂的 YBa ₂ Cu ₃ O _7-δ的T线性电阻率当通过共振非弹性 X 射线散射检测到的 CDW 幅度被抑制时，薄膜就会恢复。这一观察表明，CDW 的开始与欠掺杂铜酸盐中T线性电阻率的偏离之间存在密切联系。我们的结果说明了使用应变控制来操纵量子材料的基态的潜力。