Chapter 13
Theoretical Generalization of the Optical
Chirality to Arbitrary Optical Media
J. Enrique Vázquez-Lozano and Alejandro Martínez
Abstract Chiroptical light-matter interaction is largely boosted in the surroundings
of complex-shaped metallic nanostructures. Multiple enhancement schemes have
been proposed, from twisted structures, such as spirals or helices, arrays of chiral
and even achiral plasmonic nanostructures, to stacked planar metasurfaces. Furthermore, there is a steadily growing trend in using assemblies of high-index dielectric nanostructures, which are actually revealing promising results in terms of the
enhancement of chiroptical effects. At any rate, whatever the type of material is, the
effects of dispersion and absorption need to be accounted for, with the only exception
of the vacuum. These considerations are often neglected, presuming media with an
ideal lossless and dispersionless behavior. However, when matter is nanostructured
to achieve more complex behaviors, as for the case of metamaterials or plasmonic
nanostructures, the effects of dispersion and losses in chiroptical interactions cannot
be disregarded at all. Hence, as with the energy, the optical chirality should also be
generalized to the case of arbitrary dispersive and lossy optical media. This is the
matter of the present chapter; namely, a thorough derivation of the optical chirality,
extending it so as to include both dispersive and dissipative effects. For simplicity,
as well as for constructiveness, we shall elaborate this theoretical analysis upon the
basis of the most complete form of the conservation law for the optical chirality.
13.1 Introduction
Just by taking a glance at the current literature on optics and nanophotonics, one can
realize that optical chirality is an active research topic that often goes hand in hand
with plasmonics and metamaterials [1, 2]. These kind of systems are actually being
regarded as the best-suited platform for strengthening, and thus for investigating,
chiral light-matter interactions [3–9]. More recently, high-index dielectric nanoparJ. E. Vázquez-Lozano (B) · A. Martínez
Nanophotonics Technology Center, Universitat Politècnica de València,
Camino de Vera s/n, 46022 Valencia, Spain
e-mail: juavazlo@ntc.upv.es
© Springer Nature Switzerland AG 2021
E. Kamenetskii (ed.), Chirality, Magnetism and Magnetoelectricity,
Topics in Applied Physics 138,
https://doi.org/10.1007/978-3-030-62844-4_13
323
Theoretical Generalization of the Optical
Chirality to Arbitrary Optical Media
J. Enrique Vázquez-Lozano and Alejandro Martínez
Abstract Chiroptical light-matter interaction is largely boosted in the surroundings
of complex-shaped metallic nanostructures. Multiple enhancement schemes have
been proposed, from twisted structures, such as spirals or helices, arrays of chiral
and even achiral plasmonic nanostructures, to stacked planar metasurfaces. Furthermore, there is a steadily growing trend in using assemblies of high-index dielectric nanostructures, which are actually revealing promising results in terms of the
enhancement of chiroptical effects. At any rate, whatever the type of material is, the
effects of dispersion and absorption need to be accounted for, with the only exception
of the vacuum. These considerations are often neglected, presuming media with an
ideal lossless and dispersionless behavior. However, when matter is nanostructured
to achieve more complex behaviors, as for the case of metamaterials or plasmonic
nanostructures, the effects of dispersion and losses in chiroptical interactions cannot
be disregarded at all. Hence, as with the energy, the optical chirality should also be
generalized to the case of arbitrary dispersive and lossy optical media. This is the
matter of the present chapter; namely, a thorough derivation of the optical chirality,
extending it so as to include both dispersive and dissipative effects. For simplicity,
as well as for constructiveness, we shall elaborate this theoretical analysis upon the
basis of the most complete form of the conservation law for the optical chirality.
13.1 Introduction
Just by taking a glance at the current literature on optics and nanophotonics, one can
realize that optical chirality is an active research topic that often goes hand in hand
with plasmonics and metamaterials [1, 2]. These kind of systems are actually being
regarded as the best-suited platform for strengthening, and thus for investigating,
chiral light-matter interactions [3–9]. More recently, high-index dielectric nanoparJ. E. Vázquez-Lozano (B) · A. Martínez
Nanophotonics Technology Center, Universitat Politècnica de València,
Camino de Vera s/n, 46022 Valencia, Spain
e-mail: juavazlo@ntc.upv.es
© Springer Nature Switzerland AG 2021
E. Kamenetskii (ed.), Chirality, Magnetism and Magnetoelectricity,
Topics in Applied Physics 138,
https://doi.org/10.1007/978-3-030-62844-4_13
323