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What ’ s Nano about Light?. December 4, 2014. Today ’ s Plan. Introduce the International Year of Light (IYL) Discuss possible partners for IYL Present NISE resources for IYL Describe the science behind two NanoDays activities If time, a surprise!. International Year of Light (IYL).
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What’s Nano about Light? December 4, 2014
Today’s Plan • Introduce the International Year of Light (IYL) • Discuss possible partners for IYL • Present NISE resources for IYL • Describe the science behind two NanoDays activities • If time, a surprise! 2
International Year of Light (IYL) “A global initiative adopted by the United Nations to raise awareness of how optical technologies promote sustainable development and provide solutions to worldwide challenges in energy, education, agriculture, communications and health.” “The science and applications of light creates revolutionary - but often unseen - technologies that directly improve quality of life worldwide.” Health Communications Economy Environment Social http://www.light2015.org/ 3
Celebrating Light 4 SPIE, http://www.youtube.com/watch?v=rcoMeWV0jZc
What’s Nano about Light? Electronics (nanostructures like thin films) Stained glass (metallic nanoparticles) Energy (nanostructures) Medicine (nanoparticles, nano-coatings) 5 SPIE, http://www.youtube.com/watch?v=rcoMeWV0jZc
Why Should You Care About the IYL? • Kids are naturally interested in light and color • This is a great opportunity for partnering with scientists • There are tons of great NISE resources (activities and videos) related to light 6
Check-in Time • Are you interested in trying to bring in scientists for IYL events? • Do you already know scientists you could contact? 7
IYL Partner Organizations 8 http://www.light2015.org/
Finding a Partner • IYL is a great time to approach scientists, because they’re supposed to be involved in outreach • What kinds of scientists/organizations are involved in IYL? • NISE has contacts in SPIE and OSA • Physicists • Material scientists/engineers • Electrical engineers • Optical engineers • SPIE (physicists/engineers) • APS (physicists) • OSA (physicists and engineers) • IEEE (engineers) APS = American Physical Society, OSA = Optical Society of America, IEEE = Institute of Electrical and Electronics Engineers 9
Check-in Time Any general questions about the International Year of Light or finding scientist partners? 10
Light-related Resources from NISE http://www.nisenet.org/events/other/international-year-light-2015 So many great resources! NanoDays activities Videos Programs 11
Light-Related Activities Many of these activities aren’t just related to light—they’re also an excellent introduction to everything that’s cool and unique about nano 12
Light-related Topics: Examples http://www.nisenet.org/ • Light in nature • Butterfly • Thin Films • Bubbles • Nanoscale-phenomena • Sunblock • Nano Gold • Invisibility • New technologies/devices • Liquid crystal displays • Thin Films 13
Light-Related Videos Nano and Me - Gold What’s Nano About Bubbles? http://vimeo.com/74400132 http://vimeo.com/31270439 http://www.nisenet.org/ 14
Check-in Time • Do you have a favorite light-related activity from NISE? If so, what is it? 15
Check-in Time • Do you have a favorite light-related activity from NISE? If so, what is it? • Do you find it challenging to describe the science behind any of NISE’s light-related activities? If so, which one(s)? 16
Absorption, Reflection, and Transmission • Sunlight and other white light contains all colors • When light hits an object, it can be • Absorbed • Reflected • Transmitted • In the case of raspberries • Green and blue are strongly absorbed • Red is only partially absorbed 17
Absorption, Reflection, and Transmission Absorption + Reflection + Transmission = 100% 18 http://design.tutsplus.com/tutorials/draw-a-shiny-make-up-mirror-with-adobe-illustrator--vector-4418
Check-in Time Why does a red apple look red? • It absorbsmost of the red light from the sun • It reflectsmost of the red light from the sun • It transmits most of the red light from the sun 19
Why does a red apple look red? • It absorbsmost of the red light from the sun • It reflectsmost of the red light from the sun • It transmits most of the red light from the sun The color of an object is not actually within the object itself. Rather, the color is in the light that shines upon it and is ultimately reflected or transmitted to our eyes. [http://www.physicsclassroom.com] Learn more here: http://www.physicsclassroom.com/class/light/Lesson-2/Color-Subtraction 20
Nano Gold (Stained Glass) 21 http://design.tutsplus.com/tutorials/draw-a-shiny-make-up-mirror-with-adobe-illustrator--vector-4418
Bulk vs Nano Gold Bulk Gold Stained glass Nano Gold 22 http://education.mrsec.wisc.edu/nanolab/gold_uv/index.html#Introduction
Size and Shape Matter At the nanoscale, size matters! At the nanoscale, shape matters, too! http://www.horiba.com/scientific/ http://commons.wikimedia.org/wiki/File:Native_gold_nuggets.jpg http://www.cat.gov.in/technology/laser/lpas/pps.html 23
How are the Colors Created? 24 http://edcvs.co/130nfaU
Resonance Causes Absorption &Scattering • Bells are a great analogy because they ring due to resonance (reverberation) • We usually think about resonance in terms of sound waves, but other waves can also undergo resonance • Metallic surfaces have surface plasmons – delocalized electrons • These electrons have wave properties 25
Resonance Causes Absorption &Scattering • Light of a specific wavelength can interact strongly with these delocalized electrons, making them resonate • We call this surface plasmon resonance • Light that interacts strongly is absorbed and/or scattered; other wavelengths of light are mainly transmitted • Produces vibrant colors • To learn more about scattering, read about how scattering causes the sky to look blue 26
Color of Reflected vs Transmitted Light Example: translucent red cup Example: Lycurgus cup But nano gold and silver have different colors in reflected vs. transmitted light Usually, reflected and transmitted colors are the same 27 http://www.shutterstock.com/pic-177894944/stock-photo-group-of-colorful-pink-orange-and-yellow-translucent-plastic-party-cups-with-color-shadows.html http://www.smithsonianmag.com/history/this-1600-year-old-goblet-shows-that-the-romans-were-nanotechnology-pioneers-787224/?no-ist
Applications of Nano Gold https://vimeo.com/channels/nisenet/66928095 28
UV Bracelets 29 http://design.tutsplus.com/tutorials/draw-a-shiny-make-up-mirror-with-adobe-illustrator--vector-4418
UV Beads 30
How UV Light Affects UV Beads • Originally beads are colorless because the molecules aren’t good at absorbing light • UV light breaks bonds and changes the structure of the molecules • This makes it possible for them to absorb light UV light 31 http://www.profbunsen.com.au/files/uvdetectionbeads.pdf
UV Beads Shine UV light Turn off UV light, then wait • When not exposed to UV light, the molecules will convert back to their original forms, and beads will once again appear clear • For older students, could investigate how temperature and other variables affect this process 32 http://www.profbunsen.com.au/files/uvdetectionbeads.pdf
Chemistry Behind Color • How do pigment and dye molecules absorb light? • Certain wavelengths of light interact with electrons and promote the electrons to a higher energy level • These wavelengths (colors) are absorbed 33 http://chemwiki.ucdavis.edu/Wikitexts/Prince_George's_Community_College/General_Chemistry_for_Engineering/Unit_1%3A__Atomic_Structure/Chapter_2%3A_Atomic_Structure/Chapter_2.3%3A_Atomic_Spectra_and_Models_of_the_Atom
UV Beads Before UV exposure, energy gaps are larger Visible light doesn’t have enough energy to promote an electron High energy 5 eV Low energy 34
UV Beads Before UV exposure, energy gaps are larger Visible light doesn’t have enough energy to promote an electron After UV exposure, energy gaps are smaller Certain colors of visible light have enough energy to promote electrons High energy [Orange bead] High energy 5 eV 2.3 eV Low energy Low energy 35
A New Invisibility Demo! Just in time for IYL, there’s a new invisibility (cloaking) demo you can try! Exploring Properties - Invisibility http://nisenet.org/catalog/programs/exploring_properties_-_invisibility Invisibility Cloak http://nisenet.org/catalog/media/invisibility_cloak 36
A New Invisibility Demo! Just in time for IYL, there’s a new invisibility (cloaking) demo you can try! http://www.rochester.edu/newscenter/ 37
The “Rochester Cloak” 4 lenses, with some way to hold them up and align them 38
The “Rochester Cloak” 39 http://www.rochester.edu/newscenter/
The “Rochester Cloak” Fairly cheap, non-consummable materials Fun way to introduce cloaking Pairs well with other NISE materials Hard to keep lenses aligned (especially near a two-year-old!) May be hard to explain 42
Resources • Stained glass (nano gold) • Good discussion of scattering: http://hyperphysics.phy-astr.gsu.edu/hbase/atmos/blusky.html • UV beads • Good discussion of pigments: http://hermes.mbl.edu/marine_org/images/animals/Limulus/vision/Wald/photosynthesis.html • Guide from Educational Innovations: http://cdn.teachersource.com/downloads/lesson_pdf/UV-AST.pdf • Inquiry-based activities • http://www.carolina.com/teacher-resources/Interactive/activities-with-uv-beads/tr30403.tr • http://www.carolina.com/teacher-resources/Document/students-plan-an-experiment-using-uv-beads/tr10866.tr • Sunblock • Great discussion of all the science behind nano sunblock; includes Powerpoint slides and lesson plans: http://nanosense.sri.com/activities/clearsunscreen/ • U. of Rochester cloaking demo • Press release: http://www.rochester.edu/newscenter/watch-rochester-cloak-uses-ordinary-lenses-to-hide-objects-across-continuous-range-of-angles-70592/ • Published article: http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-22-24-29465%20 • This group has also developed another cloaking device that uses mirrors: https://www.youtube.com/watch?v=GAmWs6zfTj8 and https://www.youtube.com/watch?v=oJb9RnAVDuE 43
Sunblock 44 http://design.tutsplus.com/tutorials/draw-a-shiny-make-up-mirror-with-adobe-illustrator--vector-4418
Sunscreens vs Sunblocks • Sunscreens use chemicals • There are also sunblocks that use minerals like zinc oxide or titanium dioxide 45 nisenet.org vitaderminstitute.com/
Sunscreens vs Sunblocks, Continued How could sunscreen and sunblock work? Sunscreen/Sunblock Sunscreen/Sunblock Sunscreen/Sunblock Skin Skin Skin Absorption Reflection Transmission 46
Sunscreens vs Sunblocks, Continued How could sunscreen and sunblock work? Sunscreen/Sunblock Sunscreen/Sunblock Sunscreen/Sunblock Skin Skin Skin Absorption Reflection Transmission Sunscreensand sunblocksboth usually work through absorption of UV rays Sunblocks are better because they absorb more of the UV rays 47
Inorganic Sunblocks Absorb UV Better ideal UVB UVA visible 48
Nano Sunblocks Traditional zinc oxide sun blocks are very visible Modern zinc oxide sun blocks are fairly invisible after application 49 http://www.tackletour.com/reviewbluelizard.html
Nano ZnO and TiO2 Reflect Less Light UVB UVA visible ideal 50