Quantum Optics Seminar by Hadiseh Alaeian

Metafluids and Parity-Time symmetric metamaterials: New optical material phases and phenomena 

Textbook conceptions of light-matter interactions have been challenged by two recent material advances -the development of metamaterials and the introduction of parity-time (PT)-symmetric media. Metamaterials allow considerable control over the electric and magnetic fields of light, so that the permittivity, permeability, and refractive index can be tuned throughout positive, negative, and near-zero values. Metamaterials have enabled negative refraction, optical lensing below the diffraction limit of light and invisibility cloaking. Complementarily, PT-symmetric media allow control over electromagnetic field distributions in systems with balanced amounts of gain and loss, so that light propagation can be asymmetric and directional. They have enabled lossless Talbot revivals, unidirectional invisibility, and, combined with non-linear media, optical isolators.

In this talk, I will elaborate on our efforts to make new types of optical and asymmetric metamaterials, including liquid metamaterials and parity-time symmetric metamaterials. First, I will describe our work on the design and demonstration of the first fluidic metamaterial. Rather than relying on top-down fabrication techniques, we utilize protein directed assembly to synthesize the constituent meta-molecules. Both individual meta-molecules and the bulk metamaterial solution show a strong isotropic magnetic polarizability at optical frequencies. Our calculations also indicate that these meta-molecules could enable negative refractive index liquids.

Then, I will introduce the new concept of Parity-Time symmetric nanophotonic materials. We show how planar and coaxial metallo-dielectric structures with balanced inclusion of gain and loss can be used for a variety of applications, including i) directional nanophotonic waveguides and modulators; ii) directional metamaterials that have different refractive indices when viewed from different sides; and iii) flat Veselago lenses which can overcome the Rayleigh diffraction limit of conventional optical microscopy. Further, I will show how these meta-materials can be used to control the emission of the electric, magnetic and chiral emitters and suggest a non-chiral platform for enantio-specific identification and selection.