Interruption of torus doubling bifurcation and genesis of strange nonchaotic attractors in a quasiperiodically forced map : Mechanisms and their characterizations

A simple quasiperiodically forced one-dimensional cubic map is shown to exhibit very many types of routes to chaos via strange nonchaotic attractors (SNAs) with reference to a two-parameter $(A-f)$ space. The routes include transitions to chaos via SNAs from both one frequency torus and period doubled torus. In the former case, we identify the fractalization and type I intermittency routes. In the latter case, we point out that atleast four distinct routes through which the truncation of torus doubling bifurcation and the birth of SNAs take place in this model. In particular, the formation of SNAs through Heagy-Hammel, fractalization and type--III intermittent mechanisms are described. In addition, it has been found that in this system there are some regions in the parameter space where a novel dynamics involving a sudden expansion of the attractor which tames the growth of period-doubling bifurcation takes place, giving birth to SNA. The SNAs created through different mechanisms are characterized by the behaviour of the Lyapunov exponents and their variance, by the estimation of phase sensitivity exponent as well as through the distribution of finite-time Lyapunov exponents.Comment: 27 pages, RevTeX 4, 16 EPS figures. Phys. Rev. E (2001) to appea

Spectral response behaviour of photoetched CdS electrodes

Photoelectrochemical studies in 1M NaOH-1M Na2S-1M S on chemically etched and photoetched surfaces of single crystal CdS electrode have been carried out. The current-voltage characteristics at 120 mW cm-2 tungsten-halogen illumination showed V, =266mV,J, = 52.08pA cm-2 and ff = 0.45 for the photoetched surface. The spectral response curve depicting the variation of absolute quantum efficiency with wavelength of incident radiation showed a maximum value of 2.26 x 10-2 at a wavelength of 510nm. The results are compared with those obtained on a chemically etched surfac

Surface treatments of fluorine doped tin oxide films

Fluorinedoped tin oxide films prepared by spray pyrolysis were subjected to chemical etching using hydrazine hydrate, mechanical polishing and electrochemical etching (cathodic), and the consequent changes in the sheet resistance and optical transmiss~on of the films are reported. Scanning electron microscopic examination revealed a change in the surface morphology of the film

Spectral response behaviour of photoetched CdS electrodes

Photoelectrochemical studies in 1M NaOH-1M Na2S-1M S on chemically etched and photoetched surfaces of single crystal CdS electrode have been carried out. The current-voltage characteristics at 120 mW cm-2 tungsten-halogen illumination showed V, =266mV,J, = 52.08pA cm-2 and ff = 0.45 for the photoetched surface. The spectral response curve depicting the variation of absolute quantum efficiency with wavelength of incident radiation showed a maximum value of 2.26 x 10-2 at a wavelength of 510nm. The results are compared with those obtained on a chemically etched surfac

Improved performance of photoetched cadmium sulphide electrodes in PEC cells

The photoelectrochemical cell comprising a chemically etched CdS single crystal electrode in 2M NaOH - 0.3M Na2S-O.1M S gave V, = 410 mV, J,, = 0.64 mA cm-2 and ff = 0.28 under approximately 120 mW cm-2 tungsten-halogen illumination. A short photoetching of the CdS electrode in a dilute HCI-HN03 mixture remarkably improved the photo output characteristics as follows: V, = 520 mV (18% increase), J, = 2.33 mA cm-2 (68% increase) and ff = 0.47 (36% increase). The enhancement is a direct result of a reduction in the density of surface defects

Preparation of thin film electrodes for electrochemical solar cells - chemical bath deposition

Many methods are available for the preparation of thin films of semiconductors used as photoelectrodes in photoelectrochemical cells. In this article, Chemical Bath Deposition (CBD) is discussed. The emphasis is on thin films particularly for use in solar energy conversion application through the electrochemical route

Sn02:f film properties: effect of electrochemical and mechanical polishing

The effect of electropolishing and mechanical polishing on the transmittance and sheet resistance of Sn02:F films prepared by using two mixed solvent media has been studied. Surface morphology changes recorded by SEM are presented

Presentation of thin film transparent tin oxide conducting contatcs

Tin oxide, indium oxide and indium tin oxide (110) films are extensively used inapplications where a high electrical conductivity and good optical transmission in the visible region are required. Highly conducting, transparent fluorine doped tin oxide films were prepared on glass substrates by spray pyrolysis employing SnCl2 instead of the commonly used SnCI4. A systematic study on the spray pyrolysis conditions, optical and electrical properties of the films obtained, the influence of air and vacuum anneallng of the fllms on their properties and also surface topography studies are presente