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Although electromagnetics is a well-established field within physics and engineering, it is also a rather dynamic one. Our ever increasing need for connectivity and the rise of medical and military applications constantly create new challenges for researchers in electromagnetics. In this thesis, unconventional methods are proposed for tackling some of these challenges by manipulating the electromagnetic fields in different regions: reactive near field, radiative near field, and far field. The first topic examined pertains to the development of antennas for Internet of Things (IoT) nodes with extremely small form factors and low power consumption. As a result, they require small and relatively efficient antennas that can be tightly integrated within the node. The antennas should be able to operate with lossy and metallic components in their near field, while maintaining adequate performance. A type of antenna, called a 3D loop, is designed to fulfill these specifications, and is used in two compact IoT systems. The second thrust aims at developing devices that generate Bessel beams and X waves in their radiative near field. Bessel beams are a class of exotic beams with nondiffracting and self-healing properties. Here, two radiator designs are presented, capable of generating Bessel beams with minimal deviation of their parameters over a broad bandwidth. This allows the generation of nondiffracting and nondispersive pulses (X waves) that remain highly localized within the device’s radiative near field. The final topic examined aims at analytically modeling the electromagnetic properties of patterned metallic sheets. Such sheets are the building blocks of metasurfaces, which are two dimensional devices that manipulate the properties of a propagating wavefront (amplitude, phase, polarization). Having analytical models for sheets that realize arbitrary electromagnetic properties significantly expedites their design, as opposed to relying on databases of simulated geometries.

We demonstrate a versatile vortex linear light bullet as a three-dimensional vortex Airy-Bessel wave packet for the first time. It combines a temporal Airy pulse with a higher order vortex Bessel beam in the spatial domain. Its non-varying feature in linear propagation is verified by three-dimensional (3D) measurements. Advanced from previously reported linear light bullets which are limited to specific materials, the vortex Airy-Bessel wave packet works as a light bullet for any material while carrying orbital angular momentum. It is believed that the versatile vortex linear light bullet is useful in many applications such as nano-lithography, nano-surgery, etc. The study of controlled collisions between optical vortices in the time domain is also reported in this thesis.

The widespread use of the electromagnetic near field, in applications ranging from high resolution imaging devices to wireless power transfer systems, has called for focusing devices with higher resolutions and larger focal lengths. This demand, however, faces a major obstacle: the diffraction limit. Due to this limit, subwavelength resolutions are only possible at near-field distances. A novel solution is proposed for overcoming the diffraction limit: near-field plates (NFPs). NFPs are non-periodically patterned surfaces that can form desired subwavelength patterns at specified near-field distances. They are simple to fabricate, robust to inherent losses, and allow the near field pattern to be stipulated. Given these advantages, they show great promise as a simple and effective method for tailoring the electromagnetic near field. In this thesis, the first reported NFP is introduced and its operation is analytically studied. The NFP concept is then advanced through several phases, addressing a major issue in each phase. NFPs suitable for practical applications are introduced, and their design and operation are described. Their ability to tailor the electromagnetic near field is verified through full-wave simulations and experiments. Finally, application areas of NFPs such as near-field probing and imaging, biomedical devices, and wireless power transfer systems are discussed.

Continuing advances in laser and photonic technology has seen the development of lasers with increasing power and increasingly short pulsewidths, which have become available over an increasing range of wavelengths. As the availability of laser sources grow, so do their applications. To make better use of this improving technology, understanding and controlling laser propagation in free space is critical, as is understanding the interaction between laser light and matter. The need to better control the light obtained from increasingly advanced laser sources leads to the emergence of beam engineering, the systematic understanding and control of light through refractive media and free space. Beam engineering enables control over the beam shape, energy and spectral composition during propagation, which can be achieved through a variety of means. In this dissertation, several methods of beam engineering are investigated. These methods enable improved control over the shape and propagation of laser light. Laser-matter interaction is also investigated, as it provides both a means to control the propagation of pulsed laser light through the atmosphere, and provides a means to generation remote sources of radiation.