12.2.4

Wave-Particle Duality

Test yourself

De Broglie Hypothesis

De Broglie suggested particle-wave duality in his PhD thesis.

Illustrative background for Light as a waveIllustrative background for Light as a wave ?? "content

Light as a wave

  • Light has properties which show that it behaves as a wave.
    • Light can produce interference patterns.
    • Light can be diffracted.
Illustrative background for Light as a particleIllustrative background for Light as a particle ?? "content

Light as a particle

  • Light also has properties which show that it behaves as a particle:
    • The photoelectric effect is explained using a particle model.
Illustrative background for De Broglie's hypothesisIllustrative background for De Broglie's hypothesis ?? "content

De Broglie's hypothesis

  • De Broglie suggested particle-wave duality.
  • He suggested that all particles can behave as a wave, and all waves can behave as particles.
  • He linked the two with his equation for the de Broglie wavelength:
    • ρ=hλ \rho = \frac{h}{\lambda}.

Electron Diffraction

If de Broglie's hypothesis is correct, then particles such as electrons should show effects such as diffraction.

Illustrative background for Electrons as a waveIllustrative background for Electrons as a wave ?? "content

Electrons as a wave

  • Following de Broglie’s hypothesis, many people wanted to find evidence of the electrons as a wave.
  • Electron diffraction was the first successful attempt.
Illustrative background for Electron diffractionIllustrative background for Electron diffraction ?? "content

Electron diffraction

  • When electrons are accelerated through a vacuum tube and interact through space in a graphite crystal, they can form an interaction pattern.
Illustrative background for Diffraction patternIllustrative background for Diffraction pattern ?? "content

Diffraction pattern

  • The electron diffraction pattern has a bright central disc, and circular bands around it.
  • As the electron speed increases, the pattern gets tighter.

Jump to other topics

1Measurements & Errors

2Particles & Radiation

3Waves

4Mechanics & Materials

5Electricity

6Further Mechanics & Thermal Physics (A2 only)

7Fields & Their Consequences (A2 only)

8Nuclear Physics (A2 only)

9Option: Astrophysics (A2 only)

10Option: Medical Physics (A2 only)

11Option: Engineering Physics (A2 only)

12Option: Turning Points in Physics (A2 only)

Go student ad image

Unlock your full potential with GoStudent tutoring

  • Affordable 1:1 tutoring from the comfort of your home

  • Tutors are matched to your specific learning needs

  • 30+ school subjects covered

Book a free trial lesson