Dear Colleagues and Students,
You are cordially invited to UNAM Nanocolloquium seminars focusing on advancements in the field of nanoscience and nanotechnology. The seminars bring us the most recent developments in these exciting fields.
The fifth talk of this fall term will be presented by Prof. Sergey V. Gaponenko*
Title: Colloidal Nano-optoelectronics: State-of-the-art and prospectives
Date: December 09, Friday
Place: UNAM Conference Room
ABSTRACT – Colloidal nano-optoelectronics is presented as emerging technological platform which opens an avenue to cheap components substituting existing devices and also to biocompatible elements that do not exist so far.
Optoelectronics offers today a plenty of components and devices both for technological instrumentation and human needs. Essentially, it is mainly based on fine vacuum deposition techniques to develop high-quality monosrystalline layers and heterostrucutres. Emerging nano-optoelectronics will couple nanoelectronics and nanophotonics together based on advances in solid state physics, optics, material and molecular science.
The colloidal approach offers multilevel bottom-up scaling including: subnanometer molecular scale interfaces, nanometer-scale semiconductor quantum dot systems, submicron photonic scale. Semiconductor nanocrystals of 1-10 nm size referred to as colloidal quantum dots are posed as the key optoelectronic component whereas lower scale molecular phenomena and upper scale photonic effects can be traced and tailored to ensure the optimal overall performance of optoelectronic devices. Semiconductor nanocrystal approach offers performance in one-, two-, and three-dimensional electron confinement by means of nanoplatelets (similar to quantum wells), nanorods (similar to quantum wires) and nanocrystals (quantum dots).
Notably, the colloidal multilevel bottom-up approach as the technological paradigm and semiconductor quantum dots as its principal physical entity, when coupled together do offer the unprecedented road map towards versatile and affordable platform where every optoelectronic component, including light emitting diodes, LEDs, lasers, photodetectors, signal processing elements (e.g. electrooptical modulators, optical switches) and various sensors can be developed in unified and cheap technological processes to compete with existing multi-base and expensivetechnological approaches when e.g. CCD-detectors are made on silicon based platform while display devices use liquid crystals and moreover, light emitting devices are based on GaN semiconductor or organic LEDs.
Coupling of semiconductor nanocrystals with plasmonic colloidal metal nanostructures offers enhancement in luminescence, absorption and scattering of light and can be purporsefully used in optoelectronic devices.
Interfacing of electronic devices with biosystems is the essential advantageous outcome of the colloidal bottom-up approach. It actually promises a tool towards optimal molecular scale interfacing and coupling which are crucially important for various human-friendly, human-sensitive and human-aid (biomedical) devices enabling both easy operation and multifaceted interaction of biological and electronic counterparts through quantum dots bioconjugation and molecular scale charge and energy transfer processes.
* Institute of Physics of the National Academy of Sciences of Belarus (NASB)
All interested are cordially invited!