De Broglie wavelength

Definition

The de Broglie wavelength is the wavelength associated with a particle and is inversely proportional to its momentum. It highlights the wave-particle duality of matter.

5 Must Know Facts For Your Next Test

1. The de Broglie wavelength $\lambda$ is given by the formula $\lambda = \frac{h}{p}$, where $h$ is Planck's constant and $p$ is the momentum of the particle.
2. It was proposed by Louis de Broglie in 1924 as part of his PhD thesis.
3. For macroscopic objects, the de Broglie wavelength is extremely small and thus not noticeable.
4. Electrons exhibit wave-like properties such as diffraction when passing through a crystal lattice due to their de Broglie wavelengths.
5. The concept of de Broglie wavelengths led to the development of quantum mechanics, influencing Schrödinger's wave equation.

Review Questions

• What equation defines the de Broglie wavelength?
• Why are de Broglie wavelengths significant for microscopic particles but negligible for macroscopic objects?
• How did the proposal of de Broglie's hypothesis contribute to quantum mechanics?

Related terms

Planck's Constant: A fundamental constant denoted by $h$, approximately equal to $6.626 \times 10^{-34}$ Js, crucial in quantum mechanics.

Wave-Particle Duality: The concept that every particle or quantum entity exhibits both wave and particle properties.

Schrödinger's Wave Equation: A key equation in quantum mechanics that describes how the quantum state of a physical system changes over time.