  Chiral excited electronic states of molecules have an intrinsic sense of
handedness, or twist, and are the active component in energy efficient display
technologies and in new photosynthetic routes to produce pharmaceuticals.
Creating chiral states is achieved by manipulating the twistiness of the
geometric molecular structure. This is a demanding problem adding complexity
due to the need to precisely control molecular geometry. Here we demonstrate a
novel concept for creating chiral excited states which does not rely on
molecular structure. Instead, it depends on hybridising a non chiral molecule
with a chiral electromagnetic field, producing a hybrid light matter chiral
polariton state. This is achieved by a symmetry controlled strong chiral-light
matter interaction between an electromagnetic mode of a chiral nanocavity and
an achiral molecule, a concept referred to as the electromagnetic enantiomer.
This electromagnetic mechanism simplifies the creation of chiral electronic
states since it is far less demanding in terms of materials design. We have
illustrated the concept using an exemplar system relevant to organic
optoelectronic technology, producing efficient circularly polarised emission
from a non-chiral emitter molecule.
