File(s) under embargo

9

day(s)

until file(s) become available

Emergent Phenomena in Anisotropic Photonics

thesis
posted on 20.04.2022, 18:42 by Emroz KhanEmroz Khan
The degree of freedom brought about by breaking the directional symmetry of space through the use of anisotropic media finds applications in numerous photonic systems. Almost all these systems are based on physical principles that are generalized extensions of their isotropic counterparts, much in the same way an ellipse is related to a circle. However, as we show, there are examples where, in the presence of loss, disorder or even coupling to the measurement apparatus, emerges a completely new behavior which is qualitatively different from the isotropic case. In this work we study these emergent phenomena found in open anisotropic photonic systems.

We demonstrate that open systems based on biaxial anisotropic medium can support exceptional points which are singularities in the parameter space of the system where the mode frequencies as well as the modes themselves coalesce. We also show that topological insulators, which are novel materials that behave as dielectric in the bulk but metallic in the surface and exhibit bianisotropy through the coupling of their electric and magnetic response, can emit thermal radiation that carries nonzero spin angular momentum. Next, after describing how the strong anisotropy of hyperbolic metamaterial can support electromagnetic fields propagating with high wavenumbers unbounded by the frequency, we show that a super-resolution imaging scheme based on such material is quite robust against substantial loss and disorder. Finally, we consider an example of an incoherent perfect absorber and show that loss and anisotropy in this case can work together to recover the ideal lossless limit for the absorbing performance. In addition to making new conceptual connections between photonics and other branches of science such as condensed matter physics, biotechnology and quantum mechanics, these new emergent phenomena are shown to have thermal, imaging and sensing applications.

Funding

National Science Foundation, Grant Nos. DMR-1120923 and DMREF- 1629276

Army Research Office, Grant No. ARO W911NF-14-1-0639

The Gordon and Betty Moore Foundation

Bilsland Dissertation Fellowship, Purdue University

History

Degree Type

Doctor of Philosophy

Department

Electrical and Computer Engineering

Campus location

West Lafayette

Advisor/Supervisor/Committee Chair

Evgenii E. Narimanov

Additional Committee Member 2

Alexandra Boltasseva

Additional Committee Member 3

Andrew M. Weiner

Additional Committee Member 4

Vladimir M. Shalaev