Enhancement of Light Absorption by Quantum Dots
April 2016 - June 2016
(Image is a dark field view of the QD-Graphene complex under the optical microscope)
This project was my senior capstone for NanoEngineering at UC San Diego. I was part of a team of three under the tutelage of Prof. Oscar Vazquez Mena, an assistant professor working on integrating graphene and nanoscale materials into devices for photovoltaics, biosensing a two-dimensional hybrid metamaterials.
The study consisted on evaluating whether a Lead Sulfide Quantum Dot (QD) based coating could enhance the light absorption capabilities of graphene. QDs are nanometer-sized semiconductor structures, one of their characteristics of interest to us is that you can tune their light absorbance to very specific wavelengths (infrared, visible, UV, etc) via changing their size. Graphene is a wonder-material made of a bidimensional carbon sheet, some of its properties include high conductivity, strength, and extremely light weight.
The goal was to apply this coating on graphene and improve its light absorption so that the complex could be used as an extremely sensitive photodetector for a wide variety of applications. To study this we had an experimental setup with an Arduino and a few LEDs namely, IR, red, green, yellow, and blue; which were directly shinning on top of the silicon chip. We built a transistor model with the chip and used an electrical probe station to measure the resistance. Upon comparing the chip with and without QDs we measured a variance of 5.9% which was inconclusive.
The study consisted on evaluating whether a Lead Sulfide Quantum Dot (QD) based coating could enhance the light absorption capabilities of graphene. QDs are nanometer-sized semiconductor structures, one of their characteristics of interest to us is that you can tune their light absorbance to very specific wavelengths (infrared, visible, UV, etc) via changing their size. Graphene is a wonder-material made of a bidimensional carbon sheet, some of its properties include high conductivity, strength, and extremely light weight.
The goal was to apply this coating on graphene and improve its light absorption so that the complex could be used as an extremely sensitive photodetector for a wide variety of applications. To study this we had an experimental setup with an Arduino and a few LEDs namely, IR, red, green, yellow, and blue; which were directly shinning on top of the silicon chip. We built a transistor model with the chip and used an electrical probe station to measure the resistance. Upon comparing the chip with and without QDs we measured a variance of 5.9% which was inconclusive.
#Graphene
#Quantum Dots
#Microscopy
#Photodetectors
