Recent gyrokinetic stability calculations have revealed that the spherical tokamak is susceptible to tearing parity instabilities with length scales of a few ion Larmor radii perpendicular to the magnetic field lines. Here we investigate this ‘micro-tearing’ mode in greater detail to uncover its key characteristics and compare it with existing theoretical models of the phenomenon. This has been...

We have measured the power dependent microwave properties of a weak link in a YBa2Cu3O7−δ thin film formed by writing a line of damage using a focused ion beam. The measurement was made using a parallel plate resonator at 5.5 GHz with the weak link written across the width of one of the plates. The ion induced damage was characterized using a TRIM computer simulation and the dc properties of si...

Diamond anvil cell techniques are now well established and powerful methods for measuring materials properties to very high pressure. However, high pressure resistivity measurements are challenging because the electrical contacts attached to the sample have to survive to extreme stress conditions. Until recently, experiments in a diamond anvil cell were mostly limited to non-hydrostatic or quas...

Polymers have lower resistance to scratching and wear than metals. Liquid lubricants work well for metals but not for polymers nor for polymer-based composites (PBCs). We review approaches for improvement of tribological properties of polymers based on inclusion of fillers. The fillers can be metallic or ceramic-with obvious consequences for electrical resistivity of the composites. Distinction...

An Al-N system optical absorption layer has been developed, to be used for Al-based metal mesh electrodes on touch screen panels. The triple-layered electrode effectively suppresses the optical reflection in both visible light and the blue color region and exhibits excellent wet etching property that accommodates micro-fabrication. Due to its high noise immunity and contact sensitivity originat...

Micro-channels are made over the Ag+/Na+ ion-exchanged soda-lime glass surface by interaction of an intense Ar+ laser beam and the silver ions inside the glass matrix. The Ar+ laser beam reduces the Ag+ ions inside the matrix. The Ag+ atoms aggregate into silver nano-clusters around the interaction area, inside the glass matrix. Aggregation of the silver atoms and the thermal effects of the int...

The mechanical response of plasma-sprayed coatings is studied by recourse to instrumented spherical micro-indentation. It is shown that the elastic moduli of the coatings can be determined in a more reliable and reproducible manner with instrumented spherical indentation than prior (Knoop) indentation methods, while at the same time minimizing damage to the coating during indentation. The resul...

A new type of fiber optic relative humidity (RH) sensor based on an agarose coated silica microsphere resonator is proposed and experimentally demonstrated. Whispering gallery modes (WGMs) in the micro resonator are excited by evanescent coupling using a tapered fiber with ~3.3 µm waist diameter. A change in the relative humidity of the surrounding the resonator air induces changes in the refra...

− This work describes a single-step constrained least-squares algorithm able to image underground electrical resistivity distributions. Using an approximate analytical solution for a spherical object embedded in a homogeneous medium yields synthetic data. A 16-electrode array yields 104 independent measurements. Shifting the electrode array parallel to itself permits us to obtain 3D images. The...