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We set the theoretical basis for scattering cancellation and cloaking of quantum particle waves. We discuss the possibility of cloaking a spherical object from an impinging matter wave by using a homogeneous monolayer with properly tailored effective mass and potential. The method, based on cancellation of scattered s and p waves, is the quantum analog of plasmonic cloaking of electromagnetic waves. We show that it may be possible to use this cloaking mechanism to make semiconductor quantum dots effectively invisible to impinging electrons, providing interesting venues in nano-optics, quantum computing, and furtive quantum sensing. [ABSTRACT FROM AUTHOR]

Extraction of electromagnetic energy by an antenna from impinging external radiation is at the basis of wireless communications and wireless power transfer (WPT). The maximum of transferred energy is ensured when the antenna is conjugately matched, i.e., when it is resonant and it has an equal coupling with free space and its load. This condition, however, can be easily affected by changes in the environment, preventing optimal operation of a WPT system. Here, we introduce the concept of coherently enhanced WPT that allows us to bypass this difficulty and achieve dynamic control of power transfer. The approach relies on coherent excitation of the waveguide connected to the antenna load with a backward propagating signal of specific amplitude and phase. This signal creates a suitable interference pattern at the load resulting in a modification of the local wave impedance, which in turn enables conjugate matching and a largely increased amount of extracted energy. We develop a simple theoretical model describing this concept, demonstrate it with full-wave numerical simulations for the canonical example of a dipole antenna, and verify experimentally in both near-field and far-field regimes. [ABSTRACT FROM AUTHOR]