One Electron at a Time

Plate 37 speaks for itself: “Each lands as a dot. Together, they're a wave.”

The Physics

Tonomura's team sent electrons one at a time through an electron biprism. Each arrived as a single dot, yet thousands of dots built up interference fringes.

Δy = λ L / d

• Δy: fringe spacing, m
• λ: electron de Broglie wavelength, m
• L: distance to the screen, m
• d: effective source separation, m

Electrons cross the biprism singly. Tonomura et al., 1989.

Sources

• A. Tonomura et al., Am. J. Phys. 57, 117 (1989).

On the poster

Plate 037, “One Electron at a Time”: the pixel-art plate with its slogan “Each lands as a dot. Together, they're a wave.”, the key equation and the facts panel shown above. Pixelated Physics. Physics. Personified.