Since its first realization by Crewe et al. in the late 60s, the STEM microscope design has fully confirmed its potentiality for capturing most signals resulting from the interaction between a primary electron beam and the target. Taking benefit of recent instrumental developments, it now offers unique performance in terms of joint spatial and spectral resolution. The richness of this multi-sig...

La2-xSrxCuO4 nanowire devices have been fabricated and characterized using electrical transport measurements. Nanowires with widths down to 80 nm are patterned using high-resolution electron beam lithography. However, the narrowest nanowires show incomplete superconducting transitions with some residual resistance at T = 4 K. Here, we report on the refinement of the fabrication process to achie...

We suggest using tapered waveguides for compensating losses of surface plasmon-polaritons in order to enhance nonlinear effects at the nanoscale. We study nonlinear plasmon self-focusing in tapered metal-dielectric-metal slot waveguides and demonstrate that, by an appropriate choice of the taper angle, we can effectively suppress the mode attenuation achieving stable propagation of a spatial pl...

Optical direct write lithography (ODWL) has the capacity for generating three dimensional arbitrary patterns. Here we examine principles for voxel refinement and relate several techniques for achieving nanoscale resolution. The influence of optics, gelation, and polymerization scaling behavior are expounded, demonstrating the necessity for adopting a multidisciplinary mindset to control both vo...

We present a detection scheme for nanoscale particles based on the gradient force and torque near a tightly focused laser beam. The focus affects the path of nanoparticles passing by and a quadrant detector records the particle trajectory. A feedback system continuously adjusts the laser power and thereby prevents the particles from being trapped. Particle size and shape can be assessed by eval...

The directional waveguiding in a 2D phononic crystal is simulated based on the analysis of equifrequency contours. This approach is utilized to investigate acoustic beam splitting in a defectfree nanostructure in the low GHz range. We find relaxed limitations regarding the source parameters compared to similar approaches in the sonic regime. Finally, we discuss the possibility to design an acou...

We demonstrate experimentally the generation and near-field imaging of nondiffracting surface waves, plasmonic Airy beams, propagating on the surface of a gold metal film. The Airy plasmons are excited by an engineered nanoscale phase grating, and demonstrate significant beam bending over their propagation. We show that the observed Airy plasmons exhibit self-healing properties, suggesting nove...

A single CW infrared laser beam can simultaneously trap and excite an individual colloidal quantum dot. Though the laser light is relatively weak, the excitation occurs through two-photon absorption. This finding eliminates the demand for an excitation light source in addition to a trapping laser in nanoscale experiments with simultaneous force-manipulation and quantum dot visualization. Also, ...

A novel method of sample cross sectioning, beam-exit Ar-ion cross-sectional polishing, has been combined with scanning probe microscopy to study thin AlxGa1-xAs/GaAs layers. Additional contrast enhancement via a citric acid/hydrogen peroxide etch allows us to report the observation of layers as thin as 1 nm. Layer thickness measurements agree with transmission electron microscopy (TEM) data to ...

Lithography-free Nanoscale PatternedGrowth of GaAs on Si(001)with Sub-100-nm Silica Nanoparticles by Molecular Beam Epitaxy S. C. Lee,* L. R. Dawson, S. H. Huang, and S. R. J. Brueck Center for High Technology Materials and Department of Electrical and Computer Engineering, University of New Mexico, 1313 Goddard SE, Albuquerque, New Mexico 87106, United States Department of Earth and Planetary ...