Spatial resolution

Spatially resolving the interference pattern

The detector allows mass selecting particles, but only with a spatial resolution of some millimetres. The interferogram, however, shows pattern at a magnitude of 100 nm.

We could use a narrow slit to scan the interference pattern. But it would only allow very few molecules to pass at once.

Since the period of the interference pattern is already determined, by the grating period due to the Talbot effect, we can employ an experimental trick. For this purpose, we can measure with a grating all stripes simultaneously and more than thousand times as many molecules can reach the detector in the same time.

From the perspective of the detector it looks like in the below applet. You can move the position of the mask and observe then the intensity distribution in the diagram.

Slit Grating Position:

Experimental challenge: Quantum interference

Go to the laboratory and follow the instructions. Once you have accomplished your task, continue here.