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Thesis (Ph. D.)--University of Rochester. Department of Physics and Astronomy, 2018., High-dimensional systems are desired for their ability to transfer large amounts of information. This dissertation focuses on the characterization and usage of high-dimensional optical systems for computational imaging, high-dimensional entanglement, and efficient secure-information transfer. Within computational imaging systems, capturing the most spatial frequencies results in sharper images. Utilizing the correlations within high-dimensional entanglement offers signal-to-noise ratio enhancements over lowlight imaging and spectroscopic systems. Finally, high-dimensional quantum channels offer a regime in which quantum data locking can encrypt information according to information-theoretic-secure standards more efficiently than classical systems. While high-dimensionality offers certain performance gains, characterizing and then harnessing high-dimensional systems for computational imaging, entanglementenhanced applications, and quantum-secure direct communication can be prohibitively difficult. This dissertation offers unique solutions to each of these problems. Compressive imaging is relied on heavily to improve measurement rates in limitedresource imaging systems. As such, compressive sensing is introduced in chapter 1 while entanglement and an experimental source of high-dimensional entangled photons is covered in chapter 2. Chapter 3 introduces Sylvester-Hadamard matrices for compressive measurement and efficient computational-recovery of high-dimensional correlations. Compressive imaging is then presented as an efficient means of converting a standard frequency-modulated continuous-wave LiDAR system into a high-resolution depth-imaging system in chapter 4. Chapter 5 introduces quantum data locking and presents one of the first experimental demonstrations made possible by the use of a large-area, high-efficiency, single-photon-counting detector array. For completeness, robust compressive sensing recovery algorithms using the alternating direction method of mul

Thesis (Ph. D.)--University of Rochester. Institute of Optics, 2016., This thesis presents mainly two methodologies for achieving practical invisibility cloaking. Thus, using commercial technologies, devices that are good approximations to an ideal cloak can be achieved - a cloak that is omnidirectional, broadband, operational for the visible spectrum, three-dimensional (3D), and phase-matching for the light field, among other attributes. We first describe ‘paraxial cloaking,’ where cloaking is considered as an imaging system. The small-angle (‘paraxial’) formalism provides a first-order design requirement for any ‘perfect’ cloaking device. A ray optics four-lens cloak (called the “Rochester Cloak”) is experimentally demonstrated, followed by theoretical work to match the phase for the entire visible spectrum. To extend our broadband, paraxial cloak to larger viewing angles, we then discretize space, angle, spectrum, and phase to approximate an ideal, omnidirectional cloak. Such ‘discretized cloaking’ is experimentally demonstrated as a digital cloak, where commercially available digital image capture and display technologies are used. In particular, we demonstrate an active cloak that uses lenticular lenslet arrays, similar to integral imaging for 3D displays. The ‘digital integral cloak’ we demonstrate is dynamic, but requires a time delay for image capture and processing, and is two-dimensional (2D) without phase-matching. Continuing improvements in commercial digital technology and computational power will minimize the resolution limitations of a digital cloak and enhance its processing speed. Thus, a wearable cloak can then be practically realized in the future.

Thesis (Ph. D.)--University of Rochester. Dept. of Physics and Astronomy, 2012., Quantum optics provides a unique avenue to investigate quantum mechanical effects. Typically, it is easier to observe the particle-like behavior of a physical object than it is to observe wave-like behavior. Optics presents us with the reverse case, observing the particle-like behavior of light is difficult. I investigate the utility and limitations of two quantum mechanical effects--weak values and spatial entanglement--in the context of experimental quantum optical communication channels. I show that weak values can be used to increase the signal power and effectively decrease the noise power in a physical communication channel, up to the standard quantum limit for signal to noise ratio. I also show show a method for decreasing the negative environmental effects on a communication channel using spatial entanglement and show that such a channel can be used to transmit over 7 bits of information per joint photon detection event.