2018-03-27-JMFrost-ElthorneParkHighSchool-LayTalk

Out-reach talk to students at Elthorne Park High School (Ealing, London), on using quantum mechanics to design new solar cell materials.

Transcript

1. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Walsh Materials Design Group, Imperial College London, UK jarvist.frost@imperial.ac.uk Building the future with quantum mechanics Jarvist Moore Frost
2. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Physics: Big ideas... Hannah Devlin, in The Guardian, February 2018.
3. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 ...by limited means. The EDGE detector, Western Australia
4. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Science is not … a collection of facts. … inherently mathematical.
5. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Science is ⇒ Think up a model for how things work. ⇒ Test it. Models that work always seem to be ~mathematical. We don't really know why.
6. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 What do scientists do all day? ~50 % - reading / writing / computing The actual 'work'. (+ lab work) ~20 % - talking / whiteboarding / meeting, immediate research group ~20 % - written communication - emails / Slack / forum posts ~10 % - travelling to conferences, giving talks, watching talks, chatting over coffee
7. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 → Not a CO2 Crisis - we have an Energy Crisis Each person in Britain (for all energy):- 10'000 kg CO2 → ~10 MWh/year 10 MWh → 36 GJ / year 1142W → ~10 Cyclists The world (2008):- = 18 TW = 18'000'000'000'000 W Art Installation, V&A museum, Christmas 2009
8. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018
9. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 ⇒What we need is Fusion! [ E=mc2 ] Opération Canopus, Fangatuafa atoll, 1968. 2.6 MT
10. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Controlled fusion: A challenge!
11. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018
12. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018
13. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 We need: = 18'000'000'000'000 W (0.01 %)
14. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Vanguard 1 (1958 – NASA) [Still in orbit...] ~5cm square silicon cells [transmitted for 7 years] We have the technology! Cost and land-use are the problems • the solar resource is low density (1kW / m^2) • ~good solar panels are 22% efficient ⇒ Would need to put solar panels on ~10% of the UK
15. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Why are solar cells not very efficient? (~22%)
16. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 White light is a mix of colours. Each of these colours is a different energy photon. (Entropy bites!)
17. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 e e h h Material with a band gap
18. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 PERL Silicon Solar Cell ~23.5% PCE
19. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Silicon grown by Czochralski process 1956 George E. Meyers, Raytheon Corp. semiconductor plant in Newton, Massachusetts, USA Credit: American Radio History ( The yellow-hot bits are 1500 degrees centigrade!
20. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 2000; Smithsonian Single crystal - 'hanging by a thread'. These are the purest materials on Earth - far far more pure than any diamond or gemstone. (Nb: lab safety is massively improved!)
21. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Do some experiments!
22. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 … experiments don't always work :(
23. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Programming There's three things you need to know. (Everything else is technique and practice.) Cray 1 supercomputer. US$ 8.86 million, 1977. Slower than a smartphone!
24. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Computers are: 1) Really stupid
25. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Computers are: 2) Really fast
26. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Computers are: 3) All identical. (Turing complete.) If you can program one of them - you can program all of them! ~£100 million 120'000 CPU cores Hosted at Uni of Edinburgh
27. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 The time independent Schrodinger equation In this equation is all of chemistry*. * (The problem is that we can't solve it exactly.)
28. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Atomic orbitals = solution of Schrodinger equation for 1 electron in a central 1/r^2 potential.
29. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 What colour is a material? How strong is it? How flexible? Does it conduct? Is it stable? Could we make it? What we learn:
30. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018
31. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018
32. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018
33. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Eigensolver ('direct diagonalisation') Eigenenergies (orbital energies) Eigenvectors (Wavefunctions)
34. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018
35. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 How fast does tunnelling occur? Quantum Tunnel
36. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Electron correlation. Why is solving the TISE hard? 1 electron ⇒ Easy!
37. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Electron correlation. Why is solving the TISE hard? 2 electrons ⇒ Hard
38. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Electron correlation. Why is solving the TISE hard? Many electrons ⇒ Impossible.
39. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018
40. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 C60 Mono-PCBM Bis-PCBM Tris-PCBM
41. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 8 Bis isomers; Angles: 36 72 60 90 180 144 120 108
42. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 45 Unique Tris Isomers... (of 24360)
43. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018
44. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018
45. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 These exist...
46. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Experiment (Differential pulse voltammetry) Theory (Density functional theory)
47. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 What about things that do not?
48. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018
49. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Sunlight is a great source of power. To get the majority of humankind's energy from it, we need new ideas: • Higher efficiency cells. • Cheap to make cells. Conclusions
50. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 The End
51. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 University vs. school No teachers :) • No register; turn up when you want; learn in your own style. • Mainly peer-to-peer (teach your friends) No teachers :( • Up to you to self motivate! • "Lack of feedback" • Feel slightly lost / unstructured environment.
52. Jarvist Moore Frost (King's College London, UK) Elthorne Park High School - Talk 27th March 2018 Thinking of physics? https://www.youtube.com/user/tibees/videos - Recent Physics graduate, now PhD student; lots of short 5' videos about learning & doing physics. http://www.feynmanlectures.caltech.edu/I_toc.html - Feynman Lectures V 1, L1-13; essentially the A-level course, at a higher level. http://theoreticalminimum.com/ - Leonard Susskind. Lectures on YouTube of 'continuing studies' students revisiting Physics. Also 3 associated books. Very much proper physics, but with a minimum of assumed prior knowledge.