Superstrate

A schematic cross-section of a p-i-n a-Si H solar cell [11] is shown in Figure 72a. In this so-called superstrate configuration (the light is incident from above), the material onto which the solar cell structure is deposited, usually glass, also serves as a window to the cell. In a substrate configuration the carrier onto which the solar cell structure is deposited forms the back side of the solar cell. The carrier usually is stainless steel, but flexible materials such as metal-coated polymer foil (e.g. polyimid) ora very thin metal make the whole structure flexible [11]. 

Quantum Gravity, Generalized Theory of Gravitation and Superstring... 

Gauglitz G. and Ingenhoff J., Influence of thin superstrate films on evanescent waves in surface waveguides, Ber Bunsen Phys Chem 1991 95 1558-1563. 

Wada, T. Nishitani, M. Negami, T. Kohara, N. Ikeda, M. Terauchi, M. 1994. Microstructural characterization of substrate-type and superstrate-type CuInSe2 thin film solar cells. Proc. 12th European Photovoltaic Solar Energy Conf. pp. 1542-1545. 

Phillips notes in the preface to ESP of Quarks and Superstrings (1999) that... 

When I said earlier that superstring theory was mathematically very difficult, I was understating the problem. It is so difficult that, as I write this, no one yet knows what the mathematical equations of the theory are. Only approximate equations are known, and these are so complicated that they can be solved only approximately. The extra dimensions add complications too, because these dimensions can be interwoven in different ways. And because there is not one superstring theory but five, thousands of different versions of the theory are possible. 

However the physicists who do research on superstring theory still face numerous problems. For example, they can t even be sure whether superstrings are entities that exist in space and time, or whether space and time might be made of superstrings. Some progress has been made in determining the ways in which the extra... 

In our own time the quest has been taken to an even deeper level, notably by physicists working in superstring theory. As I write this, no one can say whether the superstring theorists will ultimately be successful. Perhaps some other way of unifying the four forces will be... 

It might turn out that no ultimate theory will ever be discovered, that scientists will find themselves probing the workings of nature at ever deeper levels. After all this is what has always happened before. Scientists originally thought that the chemical elements were the fundamental components of the universe. Then the physicists showed that they were not, by discovering first that atoms were composed of smaller particles and then that some of these particles themselves had components. Then superstring theory introduced the idea that even smaller entities were fundamental. 

Nowadays we hear a great deal about physicists ongoing effort to understand the nature of the universe s ultimate constituents. Numerous books are written about the physics of elementary particles, about the hypothetical objects known as superstrings, and about the dark matter that constitutes a large part of the universe s mass. Millions of words are written about attempts to probe their mysteries. 

As technically advanced as superstring theory sounds, superstring theory could have been developed a long time ago according to string-theory guru Edward Witten, a theoretical physicist at the Institute for Advanced Study in... 

Princeton. For example, he indicates that it is quite likely that other civilizations in the universe discovered superstring theory and then later derived Einstein-like formulations (which in our world predate string theory by more than half a century). Unfortunately for experimentalists, superstrings are so small that they are not likely to ever be detectable by humans. If you consider the ratio of the... 

John Horgan, an editor at Scientific American, recently published an article describing what other researchers have said of Witten and superstrings in ten dimensions. One researcher interviewed exclaimed that in sheer mathematical mind power, Edward Witten exceeds Einstein and has no rival since Newton. 

It is confusing that people use the word hyperspace to refer to both the fictitious fourth spatial dimension used in extrinsic coordinates (essentially a gimmick in which to see balloons and holes in space) found in ordinary general relativity, and also higher physical dimensions in which superstrings live. 

M-theory in eleven dimensions gives rise to the five competing string theories in ten dimensions (two heterotic theories, Type I, Type IIA, and Type IIB). When the extra dimension curls into a circle, M-theory yields the Type IIA superstring. On the other hand, if the extra dimension shrinks to a line segment, M-theory yields one of the heterotic strings. 

Horgan, J. (1991) The Pied Piper of superstrings. Scientific American. November 265(5) 42-44. 

Schematic diagrams of the CdTe and C1(G)S cells are shown in Figure 9.1. The main difference in their construction is that the CdTe cell is a superstrate...

M. B. Green, J. H. Schwarz, and E. Witten, Superstring Theory, Cambridge, Univ. Press, Cambridge, UK, 1987. 

Polchinslri, J.G. String Theory Superstring Theory> and Beyond, Vol. 2, Cambridge University Press, New York, NY, iyy8. 

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