  The interplay among frustrated lattice geometry, nontrivial band topology and
correlation yields rich quantum states of matter in Kagome systems. A series of
recent members in this family, AV3Sb5 (A= K, Rb, Cs), exhibit a cascade of
symmetry-breaking transitions, involving the 3Q chiral charge ordering,
electronic nematicity, roton pair-density-wave and superconductivity. The
nature of the superconducting order is yet to be resolved. Here, we report an
indication of chiral superconducting domains with boundary supercurrents in
intrinsic CsV3Sb5 flakes. Magnetic field-free superconducting diode effect is
observed with polarity modulated by thermal histories, suggesting dynamical
superconducting order domains in a spontaneous time-reversal symmetry breaking
background. Strikingly, the critical current exhibits the double-slit
superconducting interference patterns when subjected to an external magnetic
field. Characteristics of the patterns are modulated by thermal cycling. These
phenomena are proposed as a consequence of periodically modulated supercurrents
flowing along certain domain boundaries constrained by fluxoid quantization.
Our results imply a chiral superconducting order, opening a potential for
exploring exotic physics, e.g. Majorana zero modes, in this intriguing
topological Kagome system.
