從La2NiO4摻雜電洞的典型系統中，了解到化合物LSC、LBC相變的過程。我們利用高解析度的X光散射研究在低溫底下摻雜電洞的La2NiO4中電荷密度波所導致的調制結構，證明調制結構形成過程中擁有二維的系統和準長程有序的系統特性以及可能形成在相變溫度附近的電荷凝態狀態。 Strontium-doped La2NiO4 (LSN) is isostructural with the high-TC cuprates, La2-xSrxCuO4 (LSC) and La2-xBaxCuO4 (LBC). With substitution of 15% Sr, LSC shows a superconducting transition at TSC=35 K, but LSN remains insulating at doping levels up to 70%. It has been suggested that stronger electron-phonon interactions in LSN are responsible for this behavior as it was recognized that electron-phonon interactions are critical for the persistent insulating character of the Mott insulator. Therefore the hole-doped La2NiO4 can serve on a prototypical system for the understanding of transport phenomena observed in compounds of LSC or LBC. Using high-resolution x-ray scattering, we investigated the modulations due to the hole-doped in La2NiO4, and demonstrated that the modulation possesses the characteristic of two-dimension in nature and quasi-long range order at low temperature and suggested the possible existence of charge liquid state around the transition temperature.
