The double-slit experiment with single atoms or molecules demonstrates both single-slit diffraction and two-slit interference. It is a fascinating experiment that reveals the wave-particle duality of matter.
In the classical double-slit experiment, a beam of light or a stream of particles is directed toward a barrier with two closely spaced slits. Behind the barrier, a screen is placed to observe the pattern of the particles that pass through the slits.
When performing the double-slit experiment with single atoms or molecules, similar principles apply. The particles, despite being considered particles, also exhibit wave-like behavior. When a single atom or molecule passes through the double slits, it can interfere with itself, leading to an interference pattern on the screen.
The interference pattern arises due to the superposition of the wavefunctions associated with the particles passing through each slit. These wavefunctions can interfere constructively or destructively, resulting in regions of enhanced or diminished particle intensity on the screen.
The interference pattern observed in the double-slit experiment demonstrates the two-slit interference aspect of the phenomenon. It reveals that matter, even when considered as particles, can exhibit wave-like behavior and interfere with itself.
Additionally, the experiment also shows single-slit diffraction. When the slits are narrow, the particles passing through them spread out as they diffract. This diffraction leads to a broader central peak and additional smaller peaks on the screen.
Therefore, the double-slit experiment with single atoms or molecules demonstrates both the single-slit diffraction phenomenon, where the particles spread out after passing through the slits, and the two-slit interference phenomenon, where the particles interfere with each other to form an interference pattern on the screen.