We measured the effects of light soaking on the electron drift mobility for three specimens of hydrogenated amorphous silicon (a-Si:H) from different laboratories. The temperature range 130-300 K was studied. The measurements in all cases reveal two temporal regimes: an early time regime associated with bandtail transport, and a later-time regime associated with deep trapping of the electrons. ...

We present a modal theory of self-trapping spatially incoherent light beams in any general nonlinear media. We find that a self-trapped incoherent beam induces a multimode waveguide which guides the beam itself by multiply populating the guided modes. The self-trapping process alters the statistics of the incoherent beam, rendering it localized. We find the conditions for self-trapping (“existe...

The observation of an unusual light-induced agglomeration phenomenon that occurs besides the trapping of the gold nanoparticles aggregates (GNAs) has been observed. The observed agglomerate has a 60-100 μm donut-shaped metal microstructure with the rate of formation dependent on the laser power used. In this paper, the forces involved and the mechanism of this further agglomeration phenomenon a...

We study light-trapping in thin-film silicon solar cells with rough interfaces. We consider solar cells made of different materials (c-Si and μc-Si) to investigate the role of size and nature (direct/indirect) of the energy band gap in light trapping. By means of rigorous calculations we demonstrate that the Lambertian Limit of absorption can be obtained in a structure with an optimized rough i...

Using soft-imprint nanolithography, we demonstrate large-area application of engineered two-dimensional polarization-independent networks of silver nanowires as transparent conducting electrodes. These networks have high optical transmittance, low electrical sheet resistance, and at the same time function as a photonic light-trapping structure enhancing optical absorption in the absorber layer ...

A three-dimensional unified electromagnetic-electronic model is developed in conjunction with a light trapping scheme in order to predict and maximize combined electron-photon harvesting in ultrathin crystalline silicon solar cells. The comparison between a bare and light trapping cell shows significant enhancement in photon absorption and electron collection. The model further demonstrates tha...

We demonstrate the use of a single fiber-optic axicon device for organization of microscopic objects using longitudinal optical binding. Further, by manipulating the shape of the fiber tip, part of the emanating light was made to undergo total internal reflection in the conical tip region, enabling near-field trapping. Near-field trapping resulted in trapping and self-organization of long chain...

We demonstrate three-dimensional trapping and orientation of individual Au nanorods by using laser light slightly detuned from their longitudinal plasmon mode. Detuning to the long-wavelength side of the resonance allows stable trapping for several minutes, with an exponential dependence of trapping time on laser power (consistent with a Kramer's escape process). Detuning to the short-wavelengt...

We demonstrate bowtie apertures that were designed and fabricated by a lift-off process to optically trap individual, 30 nm, silica-coated quantum dots (scQD). Simulations and experiments confirm the trapping capability of the system with a relatively low continuous wave trapping flux of 1.56 MW/cm at 1064 nm. Additionally, the scQD emits upon trapping via two-photon excitation from the trappin...