Congratualtion, Chandan's paper accepted in Advanced Functional Materials.
Title: Quantum dot / carbon nanotube hybrid phototransistor with enhanced optical Stark effect
Authors: Chandan Biswas, Hyun Jeong, Mun Seok Jeong, Woo Jong Yu, Didier Pribat, and Young Hee Lee
Abstract: Enhanced carrier-carrier interactions in hybrid nanostructures exhibit exceptional electronic and optoelectronic properties. Carbon nanotubes demonstrate excellent switching behavior with high on/off ratio and high mobility but do not show photoresponse in the visible range, whereas quantum dots shows excellent optical response in various optical ranges which can be tuned with diameter. Here we show a simple and effective way to develop hybrid phototransistor with extraordinary optoelectronic properties by decorating semiconducting QDs on singlewalled carbon nanotube (SWCNT) surface. This hybrid structure demonstrates clear negative photoresponse and optical switching behavior, which could be further tuned by applying external gate bias. Clear type conversion of SWCNT transistor from p-type to n-type caused by a charge transfer from attached QDs to CNT was demonstrated. Moreover, this hybrid structure also demonstrates an enhancement in ‘optical Stark effect’ without applying any external electric field. Charged SWCNT surface plays a key role behind the enhancement of optical Stark effect in QDs. The carrier dynamics of the QD and CNT heterostructures system highlights the potential application opportunity of the quantum dot systems, which can be adaptable to the current technologies.