Time-varying media have recently emerged as a new paradigm for wave manipulation, due
to the synergy between the discovery of highly nonlinear materials, such as epsilon-near …

The law of reciprocity in acoustics and elastodynamics codifies a relation of symmetry
between action and reaction in fluids and solids. In its simplest form, it states that the …

Wireless power transfer—the transmission of electromagnetic energy without physical
connectors such as wires or waveguides—typically exploits electromagnetic field control …

Metamaterials are rationally designed composites aiming at effective material parameters
that go beyond those of the ingredient materials. For example, negative metamaterial …

Topological insulators are new phases of matter whose properties are derived from a
number of qualitative yet robust topological invariants rather than specific geometric features …

Emerging interest to synthesize active, engineered matter suggests a future where smart
material systems and structures operate autonomously around people, serving diverse roles …

Spatial stiffness modulations defined by the sampling of a two-dimensional surface provide
one-dimensional elastic lattices with topological properties that are usually attributed to two …

We experimentally demonstrate temporal pumping of elastic waves in an electromechanical
waveguide. Temporal pumping exploits a virtual dimension mapped to time, enabling the …

Research on breaking time-reversal symmetry to realize one-way wave propagation is a
growing area in photonic and phononic crystals and metamaterials. In this Letter, we present …

Space-time-varying materials pledge to deliver nonreciprocal dispersion in linear systems
by inducing an artificial momentum bias. Although such a paradigm eliminates the need for …