The direct bandgap occurs when these maximum and minimum points are aligned along the same wave vector.    From Wordnik.com.  [Featured Articles - Encyclopedia of Earth] Reference

The bandgap is the difference between the maximum energy point in the valence band and the minimum point in the conduction band.    From Wordnik.com.  [Featured Articles - Encyclopedia of Earth] Reference

The indirect bandgap occurs when the maximum valence point and minimum conduction point are not aligned on the same wave vector.    From Wordnik.com.  [Featured Articles - Encyclopedia of Earth] Reference

The bandgap of GaAs corresponds to wavelengths longer than 1 micron.    From Wordnik.com.  [Living the Big Bang Theory Life] Reference

If a photon has energy less than the bandgap, it's merely reflected or thermalized, which means it does no good at all.    From Wordnik.com.  [Analog Science Fiction and Fact]

If silicon is alloyed with other materials like germanium, amorphous silicon could reach a lower, and thus more optimal, bandgap.    From Wordnik.com.  [Photovoltaics] Reference

Another efficiency -- i.e., practicality -- issue with wide-bandgap superconductors is that fact that only high-energy photons work.    From Wordnik.com.  [Analog Science Fiction and Fact]

IBM opens up graphene bandgap, edges closer to commercialization.    From Wordnik.com.  [Joystiq] Reference

"Direct observation of a widely tunable bandgap in bilayer graphene," by Yuanbo Zhang.    From Wordnik.com.  [Energy News - Energy Technology - Energy Business - Energy and the Environment] Reference

These photovoltages were significantly higher than bismuth ferrite's electronic bandgap.    From Wordnik.com.  [ Global Warming RSS Newsfeed] Reference

Crystalline silicon's direct bandgap is 3.4 electron volts (eV) and the indirect bandgap is.    From Wordnik.com.  [Featured Articles - Encyclopedia of Earth] Reference

"Having no bandgap greatly limits graphene's uses in electronics," says Feng Wang of the U.S.    From Wordnik.com.  [Energy News - Energy Technology - Energy Business - Energy and the Environment] Reference

The absorption peak in each spectrum provided a direct measurement of the bandgap at each gate voltage.    From Wordnik.com.  [EurekAlert! - Breaking News] Reference

Theory predicts that a tunable bandgap may be engineered by periodic modulations of the graphene lattice.    From Wordnik.com.  [Naturejobs - All Jobs] Reference

Silicon, a semiconductor, is the material of choice for solar cells in large part because of its bandgap.    From Wordnik.com.  [PhysOrg.com - latest science and technology news stories] Reference

"Creating and especially controlling a bandgap in bilayer graphene has been an outstanding goal," says Wang.    From Wordnik.com.  [Energy News - Energy Technology - Energy Business - Energy and the Environment] Reference

'But the way the cell is fabricated means we're not dependent on the bandgap energy like silicon solar cells.    From Wordnik.com.  [The Engineer - News] Reference

In the case of graphene, the maximum bandgap the researchers could produce was 250 milli-electron volts (meV).    From Wordnik.com.  [Science Blog - Science news straight from the source] Reference

These inclusions have a narrower forbidden bandgap than the forbidden band of the material in the surrounding layer.    From Wordnik.com.  [LEDs Magazine Products] Reference

"This in turn makes it possible to increase the photovoltage values well above the electronic bandgap of the material.".    From Wordnik.com.  [ Global Warming RSS Newsfeed] Reference

Nature Nanotechnology that describes this work titled, "Above-bandgap voltages from ferroelectric photovoltaic devices.".    From Wordnik.com.  [EurekAlert! - Breaking News] Reference

In contrast, silicon has a bandgap of one electron volt, making it good for processing discrete digital signals, Lin said.    From Wordnik.com.  [PCWorld] Reference

Silicon's bandgap is just wide enough so that electrons can easily cross it once they are hit by photons of visible light.    From Wordnik.com.  [PhysOrg.com - latest science and technology news stories] Reference

When electricity passes through a semiconductor, it can emit a photon, whose color is determined by the material's bandgap.    From Wordnik.com.  [PhysOrg.com - latest science and technology news stories] Reference

Semiconductors, for example, can be turned off because of a finite bandgap between the valence and conduction electron bands.    From Wordnik.com.  [Science Blog - Science news straight from the source] Reference

The inner layer of the antenna contains nanotubes with a small bandgap, and nanotubes in the outer layer have a higher bandgap.    From Wordnik.com.  [Daily News & Analysis] Reference

In bilayer graphene, however, as Wang's team demonstrated, the bandgap is variable and can be controlled by an electrical field.    From Wordnik.com.  [Energy News - Energy Technology - Energy Business - Energy and the Environment] Reference

YouTube's new Music Discovery Project and Playlist Creation Tool IBM opens up graphene bandgap, edges closer to commercialization.    From Wordnik.com.  [Joystiq [PlayStation]] Reference

IBM opens up graphene bandgap, edges closer to commercialization Mega Man Zero Collection arrives in North America in 'early summer'.    From Wordnik.com.  [Autoblog] Reference

Nanoptek's scientists achieve this bandgap shift by growing titania films onto nanostructures that are essentially very small arches.    From Wordnik.com.  [Marketwire - Breaking News Releases] Reference

This new route to energy production overcomes the bandgap voltage limitation that continues to plague conventional solid-state solar cells.    From Wordnik.com.  [ Global Warming RSS Newsfeed] Reference

But a bandgap can be introduced if the mirror-like symmetry of the two layers is disturbed; the material then behaves like a semiconductor.    From Wordnik.com.  [EurekAlert! - Breaking News] Reference

Also has a zero bandgap and thus behaves like a metal.    From Wordnik.com.  [Energy News - Energy Technology - Energy Business - Energy and the Environment] Reference

A, PETE efficiency for the AM1. 5 direct+circumsolar spectrum as a function of bandgap.    From Wordnik.com.  [Naturejobs - All Jobs] Reference

Wide-bandgap Electronics to See Strong Growth as Substrates Improve, says Strategies Unlimited.    From Wordnik.com.  [Tekrati Weblog] Reference

"The bandgap energy of the bismuth ferrite is equivalent to 2.7 volts.    From Wordnik.com.  [ Global Warming RSS Newsfeed] Reference

But there's a catch: graphene has no bandgap.    From Wordnik.com.  [EurekAlert! - Breaking News] Reference

LEDs, telecoms components and wide-bandgap.    From Wordnik.com. Reference