The work horse of optics is the ray picture – i.e., the short-wavelength limit of Maxwell’s wave equations. In the form of the paraxial approximation, it is also the backbone of conventional optical resonator theory. Without such approximations, one is forced to resort to numerical solutions of the full wave equations, which in general reduces resonator design to trial-and-error. An exception a...

We report experimental and three-dimensional discrete dislocation dynamics measurements to characterize the effect of high starting dislocation density on size-affected flow. Microcrystals were focused ion beam milled into a pre-strained bulk Ni single crystal to obtain a dense heterogeneous dislocation cell structure. The strength-scaling exponent is shown to decreases considerably with increa...

We have studied the photochromic reaction of p-hydroxycinnamic-thiophenyl ester in the microcrystalline state. We attributed the fluorescence spectral evolution of the microcrystal, under UV irradiation, to the photoinduced trans-to-cis isomerization. The photocyclic behavior of the chromophore was demonstrated by cis-to-trans back reaction under a subsequent visible light irradiation. In addit...

Higher order multiphoton-pumped polarized lasers have fundamental technological importance. Although they can be used to in vivo imaging, their application has yet to be realized. Here we show the first polarized three-photon-pumped (3PP) microcavity laser in a single host-guest composite metal-organic framework (MOF) crystal, via a controllable in situ self-assembly strategy. The highly orient...

We describe an optical scattering instrument designed to assess the shapes and sizes of microscopic atmospheric cloud particles, especially the smallest ice crystals that can profoundly affect cloud processes and radiative properties yet cannot be seen clearly using in situ cloud particle imaging probes. The new instrument captures high-resolution spatial light scattering patterns from individu...