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Photoconductive response in organic charge transfer interfaces with high quantum efficiency
Helena Alves1, Rui M Pinto, Ermelinda S Maçôas
1INESC-MN and IN, University of Lisbon, Rua Alves Redol 9, 1000-029 Lisboa, Portugal. halves@inesc-mn.pt
Nature Communications
|May 16, 2013
Summary
Organic single-crystal interfaces exhibit unprecedented photoconductive behavior. This breakthrough in organic electronics enables high-performance photonic applications with nearly 100% external quantum efficiency.
Area of Science:
- Materials Science
- Organic Electronics
- Photonic Applications
Background:
- Organic semiconductors offer unique properties for diverse applications.
- Crystalline organic materials demonstrate superior electronic performance compared to disordered forms.
- Current applications of organic single crystals are limited, primarily to field-effect transistors.
Purpose of the Study:
- To report the first instance of photoconductive behavior in single-crystal charge-transfer interfaces.
- To explore the potential of organic single crystals in novel photonic applications.
Main Methods:
- Fabrication and characterization of a rubrene/7,7,8,8-tetracyanoquinodimethane single-crystal interface.
- Measurement of photoconductive properties, including responsivity and external quantum efficiency.
Main Results:
- The rubrene/7,7,8,8-tetracyanoquinodimethane system demonstrated significant photoconductive behavior.
- A responsivity of 1 A/W was achieved, corresponding to an external quantum efficiency approaching 100%.
Conclusions:
- Organic single-crystal interfaces can exhibit efficient photoconductivity.
- This finding opens new avenues for utilizing organic single crystals in advanced photonic devices.
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