Kogar A, de la Pena G A, Lee Sangjun, Fang Y, Sun S X-L, Lioi D B, Karapetrov G, Finkelstein K D, Ruff J P C, Abbamonte P, Rosenkranz S
Department of Physics and Materials Research Laboratory, University of Illinois, Urbana, Illinois 61801, USA.
Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Phys Rev Lett. 2017 Jan 13;118(2):027002. doi: 10.1103/PhysRevLett.118.027002. Epub 2017 Jan 11.
X-ray diffraction was employed to study the evolution of the charge density wave (CDW) in Cu_{x}TiSe_{2} as a function of copper intercalation in order to clarify the relationship between the CDW and superconductivity. The results show a CDW incommensuration arising at an intercalation value coincident with the onset of superconductivity at around x=0.055(5). Additionally, it was found that the charge density wave persists to higher intercalant concentrations than previously assumed, demonstrating that the CDW does not terminate inside the superconducting dome. A charge density wave peak was observed in samples up to x=0.091(6), the highest copper concentration examined in this study. The phase diagram established in this work suggests that charge density wave incommensuration may play a role in the formation of the superconducting state.
采用X射线衍射研究了CuₓTiSe₂中电荷密度波（CDW）随铜插入量的演变，以阐明CDW与超导性之间的关系。结果表明，在x = 0.055(5)左右，与超导性开始时一致的插入值处出现了CDW失配。此外，发现电荷密度波在比先前假设更高的插入剂浓度下仍然存在，表明CDW在超导穹顶内并未终止。在高达x = 0.091(6)的样品中观察到了电荷密度波峰，这是本研究中检测的最高铜浓度。这项工作建立的相图表明，电荷密度波失配可能在超导态的形成中起作用。
