The twist effect of the class of bi-isotropic materials is caused by the chirality and non-reciprocity of the structure of the media, in which the electric and magnetic field of an electromagnetic wave (or simply, light) interact in an unusual way.
These simple mediums are called isotropic, and the relationships between the fields can be expressed using constants.
[1] ξ and ζ can be further related to the Tellegen (referred to as reciprocity) χ and chirality κ parameter after substitution of the above equations into the constitutive relations, gives Pasteur media can be made by mixing metal helices of one handedness into a resin.
Care must be exercised to secure isotropy: the helices must be randomly oriented so that there is no special direction.
When the dipoles align themselves to the electric field component of the EM wave, the magnets will also respond, as they are bounded together.