The experimental evidence supporting the wave-particle duality of electrons (and other subatomic particles) comes from a range of experiments that have been conducted over several decades. These experiments provide compelling evidence for the dual nature of electrons and support the understanding that they can behave both as waves and particles.
Double-slit experiment: One of the most famous experiments demonstrating the wave-particle duality is the double-slit experiment. In this experiment, a beam of electrons is passed through a barrier with two slits. The resulting pattern on a screen behind the barrier shows an interference pattern, similar to what is observed with waves, indicating that electrons can exhibit wave-like behavior.
Diffraction experiments: Electron diffraction experiments, such as electron diffraction through a crystal lattice, also provide evidence for the wave nature of electrons. The diffraction patterns observed are consistent with the diffraction patterns of waves passing through a similar arrangement, indicating that electrons can undergo diffraction like waves.
Particle detectors: Experimental setups that detect individual electrons, such as particle detectors or electron microscopes, show that electrons behave as particles. The detection of individual electron interactions and their localized impacts on detectors suggest their particle-like nature.
Scattering experiments: Scattering experiments involving electrons, such as electron-electron scattering or electron-proton scattering, provide evidence for the particle-like nature of electrons. These experiments measure the deflection or change in momentum of the scattered electrons, which is consistent with the behavior of particles undergoing collisions.
It's important to note that these experiments do not directly "observe" the wave or particle nature of electrons. Rather, they provide evidence through the behavior and outcomes observed in experiments, which are consistent with the predictions of quantum mechanics and the wave-particle duality.
In summary, the evidence from various experiments, including the double-slit experiment, electron diffraction, particle detectors, and scattering experiments, supports the conclusion that electrons exhibit both wave-like and particle-like behavior, depending on the experimental setup and measurement being performed.