title: Photonic doping of epsilon-near-zero media.
abstract: Doping a semiconductor with foreign atoms enables the control of its electrical and optical properties. We transplant the concept of doping to macroscopic photonics, demonstrating that two-dimensional dielectric particles immersed in a two-dimensional epsilon-near-zero medium act as dopants that modify the medium's effective permeability while keeping its effective permittivity near zero, independently of their positions within the host. The response of a large body can be tuned with a single impurity, including cases such as engineering perfect magnetic conductor and epsilon-and-mu-near-zero media with nonmagnetic constituents. This effect is experimentally demonstrated at microwave frequencies via the observation of geometry-independent tunneling. This methodology might provide a new pathway for engineering electromagnetic metamaterials and reconfigurable optical systems.
authors.affiliation: Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Iñigo
authors.identifier: 0000-0003-2620-6392
authors.initials: I
authors.lastname: Liberal
authors.affiliation: Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA.|Department of Physics, The American University in Cairo, Cairo, Egypt.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Mahmoud
authors.affiliation: Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA.|Department of Electronic Engineering, Tsinghua University, Beijing 100084, China.
authors.forename: Yue
authors.identifier: 0000-0001-9562-3136
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Brian
authors.identifier: 0000-0001-9354-125X
authors.initials: B
authors.lastname: Edwards
authors.affiliation: Department of Electrical and Systems Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA. engheta@ee.upenn.edu.
authors.forename: Nader
authors.identifier: 0000-0003-3219-9520
authors.initials: N
authors.lastname: Engheta