Diamond is not only the hardest material in nature, but is also an extreme electronic material with an ultrawide bandgap, exceptional carrier mobilities, and thermal conductivity. Straining diamond can push such extreme figures of merit for device applications. We microfabricated single-crystalline diamond bridge structures with ~1 micrometer length by ~100 nanometer width and achieved sample-wide uniform elastic strains under uniaxial tensile loading along the [100], [101], and [111] directions at room temperature. We also demonstrated deep elastic straining of diamond microbridge arrays. The ultralarge, highly controllable elastic strains can fundamentally change the bulk band structures of diamond, including a substantial calculated bandgap reduction as much as ~2 electron volts. Our demonstration highlights the immense application potential of deep elastic strain engineering for photonics, electronics, and quantum information technologies.

No abstract

Hollow micro/nanolattices have emerged in recent years as a premium solution compared to conventional foams or aerogels for mechanically robust lightweight structures. However, existing hollow metallic micro/nanolattices often cannot exhibit high toughness due to the intrinsic brittleness from localized strut fractures, limiting their broad applications. Here, we report the development of hollow CoCrNi medium-entropy alloy (MEA) nanolattices, which exhibit high specific energy absorption (up to 25 J g−1) and resilience (over 90% recoverability) by leveraging size-induced ductility and rationally engineered MEA microstructural defects. This strategy provides a pathway for the development of ultralight, damage-resistant metallic metamaterials for a myriad of structural and functional applications.

No abstract

No abstract