Introduction to Nanotechnologysburns/EE1001Fall2016/EE... · What is Nanotechnology? A human hair...
Transcript of Introduction to Nanotechnologysburns/EE1001Fall2016/EE... · What is Nanotechnology? A human hair...
Introduction to Nanotechnology
Dr. Jing BaiAssociate Professor
Director of Graduate Studies (DGS)
Department of Electrical EngineeringUniversity of Minnesota Duluth
October 25, 20161
Outline
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What is nanotechnology?
Applications of nanotechnology
Approaches of nanotechnology
My research on nanotechnology
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What is Nanotechnology?
A human hair is 50,000 – 80,000 nanometers wide and grows ~10 nm every second (~600 nm every
minute)
Nanotechnology is the understanding and control of matter at dimensions of roughly 1 to 100 nanometers, where unique phenomena enable novel applications
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Why is Nanoscale So Special?• Materials at nanoscale
can have very differentchemical reactivitycompared to that in themacroscopic forms (e.g.,gold)
• Chemical reactions with nanoscale materials can be very fast due tovastly increased surface area per unit mass
• Quantum effects bring unique mechanical, electrical, photonic andmagnetic properties
• New forms of commonchemical elements atnanoscale possessspecial material properties
BuckyballQuantum wells
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Applications of Nanotechnology• Drugs and pharmaceuticals
• Nanoscale optical and electronic devices
• High-end flexible displays
• Energy devices
• Cosmetics
• Defense and security
• Nano-biotechnology
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Nanotechnology in Drug Delivery
Example: the use of nanoparticles to deliver drugs to cancer cells.Particles are engineered so that they are attracted to diseasedcells, which allows direct treatment of those cells. This techniquereduces damage to healthy cells in the body.
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Nanotechnology in Defense and Security
• Sensor system based on nanotechnology could detect biologicalagents
• Nanomaterials (such as CNT) mixed in fabrics of soldiers’uniforms could protect soldiers from dangers such as hightemperature, impacts and chemicals.
Nano-biosensor by NASA Carbon nanotube (CNT)
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Nanotechnology in Electronics
• Flexible electronic devices are stretchable and wearable. Theyhave applications in display screens, electronic interconnects,data storage and biomedical field.
• Nanomaterials (e.g., graphene, CNT and nanowires) and elasticpolymers play vital roles in flexible electronics.
Flexible electronics Graphene
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Approaches of Nanotechnology
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My Research in Nanotechnology
• Quantum-cascade lasers (QCL) – Nanoscale
lasers
• Nanostructured photovoltaic devices – Nanoscale
energy devices
• Electronic skin pressure sensor array for
colonoscopy – Nanoscale biomedical sensors
Quantum-Cascade Lasers (QCL)
One electron emits Nphotons to generatehigh output power
Typically N=20-50stages make up asingle QCL.
Electric field
ħω
ħω
Cascade effects
1111
ħω
Cross section of a QCL: Note that each layer thickness is a
few nanometers
10m
One layer
Dime coin QCL
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• Engineer the semiconductor band-structure to optimize the absorption range in the solar spectrum
• Incorporate the anti-reflection coating formed by nano-fibers to enhance the light trapping
Improvement of PV Efficiency Using Nanotechnology
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Solar Cells with Metallic Nanostructures
Absorption spectrum of a metamaterial absorber with array of nanospheres
Two types of fabricated nanostructures
Comparison between experimental measurement
and simulation results
Experimental verification of absorption enhancement of nano-
arrays
|E|
= 724 nm
|E|
= 600 nm m
in
max
Efficient absorber design based on plasmonic Fano resonance
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Electronic Skin Pressure Sensor Array for Colonoscopy
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My Contact Information
Email: [email protected]: (218)726-8606Office: MWAH 255URL: http://www.d.umn.edu/~jingbai/