Abstract Although multiphoton-pumped lasing from a solution of chromophores is important in the emerging fields nonlinear optofluidics and bio-photonics, conventionally used organic dyes are often rendered unsuitable because relatively small multiphoton absorption cross-sections low photostability. Here, we demonstrate highly photostable, ultralow-threshold biexcitonic colloidal CdSe/CdS nanoplatelets within cuvette-based Fabry–Pérot optical resonator. We find that surprisingly exhibit an...

Experimental studies of the tensile behavior metallic nanowires show a wide range failure modes, ranging from ductile necking to brittle/localized shear failure-often in same diameter wires. We performed large-scale molecular dynamics simulations copper with nanowire lengths and provide unequivocal evidence for transition mode change length. Short fail via serrated stress-strain curves, while long wires exhibit extreme localization abrupt failure. developed simple model predicting critical...

Strong-field laser-molecule interaction forms much of the basis for initiating and probing ultrafast quantum dynamics. Previous studies aimed at elucidating origins vibrational coherences induced by intense laser fields have been confined to diatomic molecules. Furthermore, in all cases examined date, wave packet motion is found be R-selective depletion; launched bond softening, though theoretically predicted, remains hitherto unobserved. Here we employ exquisite sensitivity femtosecond...

The mechanical reliability of alloys produced by Laser-Powder Bed Fusion (LPBF) is a key concern limiting their practical insertion into structural applications. While it generally accepted that the presence process induced defects such as lack-of-fusion porosity influences strain to failure, unclear what aspects defect distribution affect properties. To this end, we measured properties and structure LPBF fabricated Ti-6Al-4V coupons at 4 different porosities. We found both strength failure...

The CoFeB/MgO interface is important not only because of its ability to act as a good spin filter, but also it exhibits significant magnetic anisotropy. However, there experimental evidence that the mineral kotoite (Mg${}_{3}$B${}_{2}$O${}_{6}$) forms at this interface, possibly result B diffusion into oxide. Recent calculations have demonstrated surprisingly filter material, despite lack cubic symmetry. It priori clear how perpendicular anisotropy affected if interface. Hereby, we performed...

Natural materials such as nacre exhibit a high resistance to crack propagation, inspiring the development of artificial composites imitating structure these biological composites. We use phase field approach study role played by elastic modulus mismatch between stiff and soft layers on propagation in bioinspired Our simulations show that introduction thin layer matrix can lead arrest propagating also branching. The branching observed model is analyzed using cohesive zone approach. Further,...

We synthesized colloidal InP/ZnS seeded CdS tetrapods by harnessing the structural stability of seed nanocrystals at high reaction temperatures needed to grow arms. Because an unexpected Type II band alignment interface core and arms that enhanced occurrence radiative excitonic recombination in CdS, these were found be capable exhibiting highly efficient multiexcitonic dual wavelength emission equal intensity spectrally distinct wavelengths ∼485 ∼675 nm. Additionally, displayed a wider range...

Empirical formulas were derived for the interface shape, mechanical properties, and electrical characteristics of accumulative roll bonded (ARB) Cu/Nb laminated materials, based on relevant literature data. These incorporated into a forward analysis model using finite element analysis, enabling calculation yield stress conductivity from spatial distribution two phases. By randomly varying layer thickness shape in two-phase conducting repeated analyses, database linking microstructural...

Bistability enables adaptive designs with tunable deflections for applications including morphing wings, robotic grippers, and consumer products. Composite laminates may be designed to exhibit bistability due pre-strains that develop during the processing of polymer matrix, enabling fast reconfiguration between two stable shapes. Unfortunately, designing bistable is challenging because their highly nonlinear behavior. Here, we propose Switching Tunneling Method address this challenge by...

Al-12Si alloy processed through additive manufacturing exhibits a complex hierarchical structure. At the mesoscale, its melt pool boundaries constitute network of weak interfaces that provides preferred pathways for crack kinking, leading to both marked anisotropy and apparent enhancement in fracture energy. In this study, multiscale cohesive zone-based computational model semi-analytical approach kinked cracks are used investigate effect configuration on energy due path tortuosity. We...

Femtosecond optical pump-probe spectroscopy resolves hitherto unobserved coherent acoustic phonons in colloidal CdSe/CdS core/shell nanoplatelets (NPLs). With increasing pump fluence, the frequency of in-plane mode increases from 5.2 to 10.7 cm-1, whereas out-of-plane remains at ∼20 cm-1. Analysis oscillation phases suggests that phonon generation mechanism transitions displacive excitation subpicosecond Auger hole trapping with fluence. The measurements yield Huang-Rhys parameters ∼10-2 for...

Composite materials are extensively used in aircraft structures, wherein they subjected to cyclic loads and subsequently impact-induced damages. Progressive fatigue degradation can lead catastrophic failure. This highlights the need for an efficient prognostic framework predict crack propagation field of structural health monitoring (SHM) composite structures improve functional safety reliability. However, achieving good accuracy growth prediction is challenging due uncertainties material...

The structures and energetics of stacking faults on the prism planes in sapphire are studied computationally using total energy methods. Both first principles methods empirical potentials used to study four competing fault ${1\overline{1}00}$ one structure ${11\overline{2}0}$. Estimates for vibrational contribution obtained shell-model potentials. calculated energies combined with anisotropic elasticity theory predict low-angle symmetric tilt boundaries.

It has been shown that the broken bonds of an unreconstructed graphene edge generate compressive stresses leading to warping. Here, we investigate energies and nanoribbons with arbitrary orientations from armchair zigzag, considering both flat warped shapes in presence absence hydrogen. We use second generation reactive empirical bond order potential calculate for clean hydrogenated edges. Using these energies, perform a Wulff construction determine equilibrium flakes as function hydrogen...