matter wave
(noun)
A concept reflects the wave-particle duality of matter. The theory was proposed by Louis de Broglie.
Examples of matter wave in the following topics:
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de Broglie and the Wave Nature of Matter
- The concept of "matter waves" or "de Broglie waves" reflects the wave-particle duality of matter.
- In quantum mechanics, the concept of matter waves (or de Broglie waves) reflects the wave-particle duality of matter.
- De Broglie's hypothesis is that this relationship $\lambda = \frac{h}{p}$, derived for electromagnetic waves, can be adopted to describe matter (e.g. electron, neutron, etc.) as well.
- Therefore, the presence of any diffraction effects by matter demonstrated the wave-like nature of matter.
- Just as the photoelectric effect demonstrated the particle nature of light, the Davisson–Germer experiment showed the wave-nature of matter, thus completing the theory of wave-particle duality.
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Wave Nature of Matter Causes Quantization
- The wave nature of matter is responsible for the quantization of energy levels in bound systems.
- To consider why wave nature of matter in bound systems leads to quantization, let's consider an example in classical mechanics.
- The wave nature of matter is responsible for the quantization of energy levels in bound systems.
- Just like a free string, the matter wave of a free electron can have any wavelength, determined by its momentum.
- Explain relationship between the wave nature of matter and the quantization of energy levels in bound systems
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Particle-Wave Duality
- Wave–particle duality postulates that all physical entities exhibit both wave and particle properties.
- Wave–particle duality postulates that all physical entities exhibit both wave and particle properties.
- De Broglie's wave (matter wave): In 1924, Louis-Victor de Broglie formulated the de Broglie hypothesis, claiming that all matter, not just light, has a wave-like nature.
- His hypothesis was soon confirmed with the observation that electrons (matter) also displays diffraction patterns, which is intuitively a wave property, as shown in .
- The wavelength of the matter wave associated with a baseball, say moving at 95 miles per hour, is extremely small compared to the size of the ball so that wave-like behavior is never noticeable.
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de Broglie and the Bohr Model
- By assuming that the electron is described by a wave and a whole number of wavelengths must fit, we derive Bohr's quantization assumption.
- The wave-like properties of matter were subsequently confirmed by observations of electron interference when scattered from crystals.
- When an electron is bound to an atom, its wavelength must fit into a small space, something like a standing wave on a string.
- Schrödinger employed de Broglie's matter waves, but instead sought wave solutions of a three-dimensional wave equation.
- (a) Waves on a string have a wavelength related to the length of the string, allowing them to interfere constructively.
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Longitudinal Waves
- An example of a longitudinal wave is a sound wave.
- Some longitudinal waves are also called compressional waves or compression waves.
- Like transverse waves, longitudinal waves do not displace mass.
- The most common pressure wave is the sound wave.
- Matter in the medium is periodically displaced by a sound wave, and thus oscillates.
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Transverse Waves
- Light is an example of a transverse wave.
- For transverse waves in matter, the displacement of the medium is perpendicular to the direction of propagation of the wave.
- A ripple on a pond and a wave on a string are easily visualized transverse waves.
- Transverse waves are waves that are oscillating perpendicularly to the direction of propagation.
- Therefore an electromagnetic wave consists of two transverse waves, visible light being an example of an electromagnetic wave.
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The Photoelectric Effect
- Electrons are emitted from matter when light shines on a surface .
- The photoelectric effect is also widely used to investigate electron energy levels in matter.
- The value of work function is an intrinsic property of matter.
- Is light then composed of particles or waves?
- This question would be resolved by de Broglie: light, and all matter, have both wave-like and particle-like properties.
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Young's Double Slit Experiment
- The double-slit experiment, also called Young's experiment, shows that matter and energy can display both wave and particle characteristics.
- The double-slit experiment, also called Young's experiment, shows that matter and energy can display both wave and particle characteristics.
- Constructive wave interference occurs when waves interfere with each other crest-to-crest (peak-to-peak) or trough-to-trough (valley-to-valley) and the waves are exactly in phase with each other.
- This amplifies the resultant wave.
- The amplitudes of waves add together.
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Diffraction
- Diffraction refers to various phenomena such as the bending of waves around obstacles and the spreading out of waves past small openings.
- In classical physics, the diffraction phenomenon is described as the apparent bending of waves around small obstacles and the spreading out of waves past small openings.
- Similar effects occur when a light wave travels through a medium with a varying refractive index, or a sound wave travels through one with varying acoustic impedance.
- Diffraction occurs with all waves, including sound waves, water waves, and electromagnetic waves such as visible light, X-rays and radio waves.
- As physical objects have wave-like properties (at the atomic level), diffraction also occurs with matter and can be studied according to the principles of quantum mechanics.
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Energy Transportation
- The force you feel from a wave hitting you at the beach is an example of work being done and, thus, energy being transfered by a wave in the direction of the wave's propagation.
- Energy transportion is essential to waves.
- It is a common misconception that waves move mass.
- Electromagnetic waves can be imagined as a self-propagating transverse oscillating wave of electric and magnetic fields .
- These properties may all be imparted to matter with which it interacts (through work).