Production of photocurrent due to intermediate-to-conduction-band transitions: a demonstration of a key operating principle of the intermediate-band solar cell.
We present intermediate-band solar cells manufactured using quantum dot technology that show for the first time the production of photocurrent when two sub-band-gap energy photons are absorbed simultaneously. One photon produces an optical transition from the intermediate-band to the conduction band while the second pumps an electron from the valence band to the intermediate-band. The detection of this two-photon absorption process is essential to verify the principles of operation of the intermediate-band solar cell. The phenomenon is the cornerstone physical principle that ultimately allows the production of photocurrent in a solar cell by below band gap photon absorption, without degradation of its output voltage.
Martí
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Instituto de Energía Solar, Universidad Politécnica de Madrid, E.T.S.I.Telecomunicación, Ciudad Universitaria s/n Madrid, Madrid 28040, Spain.
Antolín
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E
Stanley
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CR
Farmer
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CD
López
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N
Díaz
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P
Cánovas
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E
Linares
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PG
Luque
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