  Controlling and channelling light emissions from unpolarized quantum dots
into specific directions with chiral polarization remains a key challenge in
modern photonics. Stacked metasurface designs offer a potential compact
solution for chirality and directionality engineering. However, experimental
observations of directional chiral radiation from resonant metasurfaces with
quantum emitters remain obscure. In this paper, we present experimental
observations of unidirectional chiral emission from a twisted bi-layer
metasurface via multi-dimensional control, including twist angle, interlayer
distance, and lateral displacement between the top and bottom layers, as
enabled by doublet alignment lithography (DAL). First, maintaining alignment,
the metasurface demonstrates a resonant intrinsic optical chirality with
near-unity circular dichroism of 0.94 and reflectance difference of 74%, where
a high circular dichroism greater than 0.9 persists across a wide range of
angles from -11 to 11 degrees. Second, engineered lateral displacement induces
a unidirectional chiral resonance, resulting in unidirectional chiral emission
from the quantum dots deposited onto the metasurface. Our bi-layer metasurfaces
offer a universal compact platform for efficient radiation manipulation over a
wide angular range, promising potential applications in miniaturized lasers,
grating couplers, and chiral nanoantennas.
