Description
Exploring the property of layered superconductors approaching the 2D limit is essential for clarifying comprehensive electronic correlation and uncovering intrinsic superconductivity mechanism [1-3]. Kagome materials $A$V$_3$Sb$_5$ ($A$ = Cs, Rb, K) have emerged as a focal point of condensed matter physics due to the intricate interplay between possible unconventional superconductivity, charge density wave (CDW) order and nematicity. However, the competition between superconductivity and CDW obscures the intrinsic superconducting ground state [4-7]. Here, we report the layer-dependent two-dimensional superconductivity in Cs(V$_{0.86}$Ta$_{0.14}$)$_3$Sb$_5$ thin flakes, where the doping of tantalum atoms completely suppresses the CDW order. Our work characterizes the emergence of 2D superconductivity upon dimensional reduction in the absence of CDW, thereby providing critical insights into the intrinsic superconducting mechanism of kagome metal.
