Explore 4D-STEM in three minutes

Explore 4D-STEM in three minutes#

Open in Colab

Question: Which scattering angles make the gold particles easiest to see?

In Colab, choose Runtime → Run all. Wait for the explorer to appear. There is nothing to upload or configure.

# @title 2. Load a small real dataset { display-mode: "form" }
from quantem.widget import Show4DSTEM
from quantem.widget.datasets import show4dstem_gold

stem_dataset = show4dstem_gold(size="medium")

Source: gold_128_npy_bin8 from Hugging Face
Full stack: (128, 128, 24, 24) uint16
Preview: (64, 64, 24, 24), scan stride 2
Sampling: [4.   4.   3.68 3.68] ['A', 'A', 'mrad', 'mrad']
Processing: real-space 4x4 block average from gold_512_npy_bin8; detector remains bin8

Try three things#

Before you click, predict which panel will change.

  1. Choose a scan point: click a particle in the right image. The diffraction pattern on the left updates.

  2. Compare angles: click BF, then ADF, below the left panel. Which image makes the particles stand out?

  3. Measure a line: turn on Profile above either panel, then click two points. Drag an endpoint to move the measurement.

Use Reset above a panel whenever you want a clean view.

# @title 3. Open the explorer { display-mode: "form" }
from sys import modules

viewer = Show4DSTEM(
    stem_dataset,
    dp_scale_mode="linear",
    offline="google.colab" not in modules,
    offline_dtype="uint16",
    save_state=True,
    precompute_virtual_images=False,
    show_fft=False,
)

viewer

What changed?#

  • A new scan point selects a different diffraction pattern.

  • A new detector integrates different scattering angles into the image.

  • A Profile plots intensity along the line you drew. No Python call is required.

Ready for microscope data? Open one dataset or several datasets.