Students' perceptions of knowledge reinforcement on indirect prosthetic dental material choices by a translational approach.

Purpose/objectives: The aim of this study is to evaluate students' perceptions of the reinforcement of knowledge via innovative, case-based, hands-on learning regarding indirect prosthetic material choice.

Methods: Six different clinical cases that represented common prosthetics were used in this simulation training. In each case, clinical pictures were associated with three-dimensional (3D)-printed replicates of final restorations and PolyJet polychromatic models with the goal of enabling students to deliberate and exchange ideas in small groups.

Nanomechanical Crystalline AlN Resonators with High Quality Factors for Quantum Optoelectromechanics.

High-quality factor (Q) mechanical resonators are crucial for applications where low noise and long coherence time are required, as mirror suspensions, quantum cavity optomechanical devices, or nanomechanical sensors. Tensile strain in the material enables the use of dissipation dilution and strain engineering techniques, which increase the mechanical quality factor. These techniques have been employed for high-Q mechanical resonators made from amorphous materials and, recently, from crystalline materials such as InGaP, SiC, and Si.

Ultraviolet-B Resonant-Cavity Light-Emitting Diodes with Tunnel Junctions and Dielectric Mirrors.

We demonstrate the first electrically injected AlGaN-based ultraviolet-B resonant-cavity light-emitting diode (RCLED). The devices feature dielectric SiO/HfO distributed Bragg reflectors enabled by tunnel junctions (TJs) for lateral current spreading. A highly doped n-AlGaN/n-GaN/p-AlGaN TJ and a top n-AlGaN current spreading layer are used as transparent contacts, resulting in a good current spreading up to an active region mesa diameter of 120 μm.

Ultrafast-nonlinear ultraviolet pulse modulation in an AlInGaN polariton waveguide operating up to room temperature.

Ultrafast nonlinear photonics enables a host of applications in advanced on-chip spectroscopy and information processing. These rely on a strong intensity dependent (nonlinear) refractive index capable of modulating optical pulses on sub-picosecond timescales and on length scales suitable for integrated photonics. Currently there is no platform that can provide this for the UV spectral range where broadband spectra generated by nonlinear modulation can pave the way to new on-chip ultrafast (bio-) chemical spectroscopy devices.