A principal cause of THz emission in semiconductor nanostructures is deeply involved with geometry, which stimulates the utilization of indirect bandgap semiconductors for THz applications. To date, applications for optoelectronic devices, such as emitters and detectors, using THz radiation have focused only on direct bandgap materials. This paper reports the first observation of strongly enhan...

In this study we proposed a new surface plasmon resonance (SPR) configuration for enhancement of biosensor sensitivity with high absorbing molecules on the sensor surface. The proposed SPR structure consists of a germanium nanowires grating coated with three graphene layers while the addition of titanium layer between gold and fused silica (substrate) prevents the gold oxidation. For transverse...

The cluster expansion enables fast alloy property computations especially useful for predicting alloy thermodynamics. It expands configurational alloy properties in basis functions called clusters with associated expansion coefficients called effective cluster interactions (ECI). The number of ECI depends on the symmetries of the system. Therefore, when applied to non-bulk low-symmetry systems,...

Retaining the high energy density of rechargeable lithium ion batteries depends critically on the cycle stability of microstructures in electrode materials. We report the reversible formation of nanoporosity in individual germanium nanowires during lithiation-delithiation cycling by in situ transmission electron microscopy. Upon lithium insertion, the initial crystalline Ge underwent a two-step...

Impurity doping is the most important technique to functionalize semiconductor nanowires. The crucial point is how the states of impurity atoms can be detected. The chemical bonding states and electrical activity of boron (B) and phosphorus (P) atoms in germanium nanowires (GeNWs) are clarified by micro-Raman scattering measurements. The observation of B and P local vibrational peaks and the Fa...