1 of 28

Glowing Stars

Materials & Preparation:

Glow-in-the dark stars
Laser pointers, LEDs, and/or UV lights of different colors (at least one should cause light emission, and one should not)
Identify method of distributing supplies to individuals and/or groups
Optional: Handout prompting audience to record a model of what’s happening

BIG IDEA: Atoms emit light when electrons move to more stable configurations, but an input of initial energy is required to excite electrons.

Description:

Using the glowing stars, the audience observes and compares the effects of different sources of light. This is connected to the energy need to excite electrons and/or down-conversion of light.

Slight modifications were made to support www.QuanTimeNM.org

TEACHER SLIDE

2 of 28

What are some sources of light?

Brainstorm as many as you can.

3 of 28

Where does the light come from?

Identify/hypothesize as many as you can.

This Photo by Unknown Author is licensed under CC BY

This Photo by Unknown Author is licensed under CC BY-SA

This Photo by Unknown Author is licensed under CC BY-SA-NC

This Photo by Unknown Author is licensed under CC BY-NC-ND

4 of 28

Let’s look at another source of light

5 of 28

Laser Safety

Only use one laser at a time
Only point laser at ceiling or tabletop
NEVER POINT LASERS AT A PERSON

6 of 28

Use the different laser pointers and LEDs to see how the glow-in-the-dark stars respond

Activity- Stars + light

7 of 28

Glowing stars intro phenomenon & initial models

Give students time to try applying the different lasers on the glow in the dark stars, make observations, and share theories

Back-pocket-questions:

What do you observe happening?

What similarities do you observe for the different lights? What differences?

What theories do you have to explain this?

8 of 28

What did you observe?

Results? Nonresults? Surprises?

9 of 28

Complete the initial model- what’s going on inside?
No right or wrong answers- just initial ideas

Model- Your theories on the glowing stars

10 of 28

Name:________________________

What’s causing the stars to glow?

Directions: Share your theories for what you think is going on before the light is shined, when the red light is shined, and when UV light is shined on the glow-in-the-dark star. Use pictures, labels, and text to share your thinking.

No Light Red Light UV Light

Theory:___________________________

_________________________________

Theory:___________________________

_________________________________

Theory:___________________________

_________________________________

11 of 28

Glowing paper- intro phenomenon & initial models

Give students time to draw, write, and explain their different theories. You can do this as individuals, in pairs, or as a whole class. If you use paper version, 11x17 is great for prompting students to share lots of ideas;

Remind students there are not right or wrong answers, we’re just looking for initial ideas

Back-pocket-questions:

What observable differences can you show?
How do you think the red and UV light are different?
What do you think is happening inside the vinyl that we can’t see?

12 of 28

How would you rank the energy of the different lights? Why?

Red light

Blue light

UV light

13 of 28

Electromagnetic Spectrum of Light

Radiation Type Gamma Ray X-ray Ultraviolet Visible Infrared Microwave Radio

Energy (kcal/mol) 10⁶ 10⁴ 10² 10 1 10^-2 10^-4 10^-6

How do your observations compare to the light on the spectrum?

14 of 28

Two models of light

scientists use to explain

its different features

Waves

Particles

15 of 28

Waves of Light

Energy (kcal/mol)

Nuclear spin transitions

Spins molecules

Vibrates molecules

Moves electrons inside atoms

Removes electrons from atoms

10⁶ 10⁴ 10² 10 1 10^-2 10^-4 10^-6

What do you notice?

Radiation Type

Effects on Matter

16 of 28

Waves of Light

10⁶ 10⁴ 10² 10 1 10^-2 10^-4 10^-6

What do you notice?

Energy (kcal/mol)

Radiation Type

About the size of

17 of 28

Why do the stars glow?

UV light

Green light

18 of 28

Excitation & Emission

Electron Excitation

Photon Emission

19 of 28

Inside the glow-in-the-dark stars

UV light

Green light

20 of 28

Update your model. What ideas would you include now?
On the back, model a different source of light.

Model- Revise your theories on the glowing paper

21 of 28

Name:________________________

What’s causing the stars to glow?

Directions: Share your theories for what you think is going on before the light is shined, when the red light is shined, and when UV light is shined on the glow-in-the-dark star. Use pictures, labels, and text to share your thinking.

No Light Red Light UV Light

Theory:___________________________

_________________________________

Theory:___________________________

_________________________________

Theory:___________________________

_________________________________

22 of 28

Summary Table: Glow Stars

What did we do:

Looked at how special materials respond to different lights

What patterns did we observe?	Why is this happening?

23 of 28

How does this connect to quantum science?

Atoms can actually be used to build quantum computers. Just like in regular computers, quantum computers store information in bits that can be either zero or one. So how do we store information in atoms?

Excited State

Ground State

Energy

For atomic qubits, ground state = “0”, excited state = “1”.
For gates, we control the qubit state by shining light (usually with lasers) on the atom to turn it from a “0” to a “1”
We look at whether our atom is glowing (aka “fluorescing”) to determine whether the final state of our quantum bit is “0” or “1”

www.QuanTimeNM.org

24 of 28

How does this connect to quantum science?

Atoms can also be used to build quantum sensors. The color of the light that an atom will absorb or fluoresce can change if the atom is near a magnet. If we can detect how much the color changes, we can measure how strong the magnet is.

Excited State

Ground State

Energy

www.QuanTimeNM.org

25 of 28

How does this connect to quantum science?

Atoms can also be used to build quantum sensors. The color of the light that an atom will absorb or fluoresce can change if the atom is near a magnet. If we can detect how much the color changes, we can measure how strong the magnet is.

Excited State

Ground State

Energy

www.QuanTimeNM.org

26 of 28

Summary Table: Glowing Paper

What patterns did we observe? The vinyl gives off green light in response to blue and UV light (not red or green) Electrons can move up when they absorb light Electrons emit light when they move down	Why is this happening? Atoms emit light when electrons move to more stable configurations. Input of initial energy is required to get electron to higher level in the first place The blue and UV light have more energy than the red or green

Sample answers from UbiQD tarp curriculum

What did we do:

Looked at how special materials respond to different lights

27 of 28

How does this connect to the tarp that helps plants grow?

What questions do we still need to explore?

Plants can’t use green light, so the special tarp absorbs some of the light and emits light that is useful for the plants.
What makes some things emit light and not others?

Mizuna

Sample answers from UbiQD tarp curriculum

28 of 28

Acknowledgments

This work is licensed under Creative Commons CC BY-NC-SA 4.0. Permission is granted for non-commercial educational use. To view a copy of this license, visit http://creativecommons.org/licenses/by-nc-sa/4.0/

Center for Integration of Modern Optoelectronic Materials on Demand

www.imod-stc.org | @IMOD_STC

The National Science Foundation Center for Integration of Modern Optoelectronic Materials on Demand is a Science and Technology Center.

This material is based upon work supported by the National Science Foundation under Grant No. DMR-2019444. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

www.imod-stc.org | @IMOD_STC

The National Science Foundation Center for Integration of Modern Optoelectronic Materials on Demand is a Science and Technology Center.

This material is based upon work supported by the National Science Foundation under Grant No. DMR-2019444. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.