  We suggest a scheme of electromagnetic chirality-induced negative refraction
utilizing magneto-electric cross coupling in a four-level atomic system. The
negative refraction can be achieved with the two chirality coefficients having
the same amplitude but the opposite phase,and without requiring the
simultaneous presence of an electric-dipole and a magnetic-dipole transition
near the same transition frequency. The simultaneously negative electric
permittivity and magnetic permeability does not require, either.
