Light-trapping in photon enhanced thermionic emitters

Photon-enhanced thermionic emission for solar concentrator systems.

Solar-energy conversion usually takes one of two forms: the 'quantum' approach, which uses the large per-photon energy of solar radiation to excite electrons, as in photovoltaic cells, or the 'thermal' approach, which uses concentrated sunlight as a thermal-energy source to indirectly produce electricity using a heat engine. Here we present a new concept for solar electricity generation, photon...

Solar energy conversion with photon-enhanced thermionic emission

Photon-enhanced thermionic emission (PETE) converts sunlight to electricity with the combined photonic and thermal excitation of charge carriers in a semiconductor, leading to electron emission over a vacuum gap. Theoretical analyses predict conversion efficiency that can match, or even exceed, the efficiency of traditional solar thermal and photovoltaic converters. Several materials have been ...

Solid-state Photon Enhanced Thermionic Emission for Solar Energy Conversion

Global climate imperatives require a worldwide shift away from greenhouse gasemitting activities such as fossil fuel combustion. Concentrated solar thermal installations are particularly appealing as they can store a fraction of their power in the form of heat to provide baseload power, yet current conversion efficiencies prevent them from reaching competitive market prices. One extremely promi...

Negative space charge effects in photon-enhanced thermionic emission solar converters

Surface-plasmon-enhanced light emitters based on InGaN quantum wells.

Since 1993, InGaN light-emitting diodes (LEDs) have been improved and commercialized, but these devices have not fulfilled their original promise as solid-state replacements for light bulbs as their light-emission efficiencies have been limited. Here we describe a method to enhance this efficiency through the energy transfer between quantum wells (QWs) and surface plasmons (SPs). SPs can increa...