  Chirality, a fundamental concept from biological molecules to advanced
materials, is prevalent in nature. Yet, its intricate behavior in specific
topological systems remains poorly understood. Here, we investigate the
emergence of hidden chiral domain wall states using a double-chain
Su-Schrieffer-Heeger model with interchain coupling specifically designed to
break chiral symmetry. Our phase diagram reveals single-gap and double-gap
phases based on electronic structure, where transitions occur without
topological phase changes. In the single-gap phase, we reproduce chiral domain
wall states, akin to chiral solitons in the double-chain model, where chirality
is encoded in the spectrum and topological charge pumping. In the double-gap
phase, we identify hidden chiral domain wall states exhibiting opposite
chirality to the domain wall states in the single-gap phase, where the opposite
chirality is confirmed through spectrum inversion and charge pumping as the
corresponding domain wall slowly moves. By engineering gap structures, we
demonstrate control over hidden chiral domain states. Our findings open avenues
to investigate novel topological systems with broken chiral symmetry and
potential applications in diverse systems.
