Flatland
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Course · written for everyone

Learn 2D materials step by step

A course in 10 levels, from what an atom is to the physics of twisted layers. Each level is a handful of short steps; each step ends with three questions to check yourself, and links into the rest of the site when you want more.

3 of 10 levels open18 steps so farNo account: your progress stays in this browser

How it works

Each level builds on the one before, so start at level 1 – or, if its ideas are familiar, try its questions first and move on when they are easy. A step takes five to ten minutes: a short text, sometimes a drawing, links to read more, and three questions. Words with a dotted underline open a short explanation from the glossary.

The course is written for anyone with school maths. The first levels need nothing else; later ones add one idea at a time, and the last reaches questions researchers are working on today. So far 3 of the 10 levels are open; the others will follow one at a time.

The levels

  1. Level 1 · 6 steps · about 15 minutes

    The toolkit

    You can picture atoms, electrons and the bonds between them, and how small a nanometre really is.

    1. How small is small
    2. Atoms and electrons
    3. What holds atoms together
    4. Crystals: atoms in a repeating pattern
    5. Light and energy
    6. Conductors, insulators and semiconductors
    Start level 1

  2. Level 2 · 6 steps · about 15 minutes

    The flat world

    You can explain to a friend what graphene is, how it was first made, and why being thin changes what a material does.

    1. A crystal one atom thick
    2. Peeling with sticky tape
    3. Why thin changes everything
    4. The family tree
    5. Where they are used today
    6. Myths worth unlearning
    Start level 2

  3. Level 3 · 6 steps · about 15 minutes

    Crystals in layers

    You can read the structure section of any material page.

    1. Lattices: triangular, honeycomb, kagome
    2. How one layer is built
    3. The gap between layers
    4. Same atoms, different stacking
    5. Symmetry
    6. Janus layers and alloys
    Start level 3

  4. Level 4 · in preparation

    Electrons and light in a sheet

    You can explain why a single layer of MoS2 glows and graphene does not.

    1. Bands and gaps
    2. Electrons, holes and doping
    3. How easily charge moves
    4. Light in and out
    5. Excitons
    6. Spin and magnetism

  5. Level 5 · in preparation

    Making them

    You can say why two samples of ‘the same’ material behave differently.

    1. Exfoliation at scale
    2. Growing films
    3. Growing crystals first
    4. Imperfect by nature
    5. Keeping them alive
    6. Building stacks

  6. Level 6 · in preparation

    Measuring them

    You can read a figure in a research paper and spot a weak claim.

    1. Seeing a flake
    2. Fingerprints in light
    3. Looking at atoms
    4. Mapping electrons
    5. Measuring current
    6. Why results do not reproduce

  7. Level 7 · in preparation

    From lab to product

    You can judge a ‘graphene breakthrough’ headline.

    1. The transistor test
    2. Contacts
    3. Joining silicon
    4. Making millions
    5. Beyond chips
    6. How ready is it?

  8. Level 8 · in preparation

    Modelling them

    You can say what a calculation of a 2D material can and cannot tell you.

    1. Density functional theory
    2. Beyond DFT
    3. Tight binding
    4. Simulating atoms in motion
    5. When calculations mislead

  9. Level 9 · in preparation

    Twists and crowded electrons

    You can follow a talk on twisted graphene and correlated electrons.

    1. Moiré patterns
    2. The magic angle
    3. Flat bands
    4. When electrons crowd
    5. Superconductivity
    6. Charge order

  10. Level 10 · in preparation

    Topology and quantum magnetism

    You can follow a research talk on topological or magnetic 2D materials.

    1. Berry curvature
    2. Topology and edge states
    3. Time-reversal symmetry
    4. Valleys
    5. Magnets one layer thick
    6. Frustration and spin liquids

Where next

BasicsWhat is a 2D material?What they are, why being thin changes everything, and how they are made. Catalogue74 material familiesWhat each one is, how it is made, and how close it is to real use. Applications18 areas, sorted by readinessFrom composites already sold by the tonne to physics with no product yet. NewsThe latest papers and storiesCollected from 137 feeds and tagged by material and audience.