Application of de Broglie Waves

Matter waves form the foundation of the theory of quantum physics. French physicist Louis de Broglie was the first one to study this phenomenon. He gave the de Broglie hypothesis in 1924. In his hypothesis he stated that electrons show a wave-like nature. He said that matter has a dual nature. Everything exists as a particle as well as a wave. However, the wavelength of everyday objects is too small compared to electrons, and they go undetected. So everyday objects are only believed to show particle-like behaviour, and the de Broglie hypothesis is applicable only to the realm of subatomic particles.  In this article we’ll discuss the applications of de Broglie waves in detail.

Understanding de Broglie Hypothesis 

By establishing an analogy with the dual nature of light (i.e. wave and particle-like), Louis de Broglie gave his hypothesis that all matter may also have wave characteristics in addition to particle properties. Three years after he gave this hypothesis, the wave character of electrons was experimentally detected. According to his hypothesis, the wavelength of any massive particle is inversely proportional to the momentum of that particle. This relation is represented as:

λ = h / mv or  λ = h / p

Here, λ is the wavelength of the particle, h is the Planck’s constant and mv=p is the momentum. 

The de Broglie hypothesis accounts for the appearance of subatomic particles at sites that are usually unexpected. This is because the waves of these subatomic particles penetrate deep into the barriers, just how sound penetrates through walls. This can be understood by taking an example of a heavy atomic nucleus. We know that through alpha decay it can eject a part of itself. But this alpha particle will have insufficient energy to break through and overcome the force barrier that surrounds the nucleus. But as a wave, this alpha particle can penetrate through that barrier, and thus, it has a finite possibility of being found outside the nucleus.  

Applications of de Broglie Waves 

The de Broglie wavelength relates the wavelength of the particles to their momentum. It accounts for a variety of phenomena. It is used to determine the probability of finding an object at a given point of the configuration space. 

Another important application of the de Broglie waves is that it is used in the construction of electron microscopes. This is due to the fact that electrons behave as waves and thus they can be used to illuminate objects in a way that is quite similar to light. Electrons are provided with energy in a manner similar to a TV tube. Then with the use of magnetic fields, they’re directed to the object that has to be viewed; electrons are then focused to create the image of that specific object. The de Broglie wavelength of the electrons is related to kinetic energies. In electron microscopy, wavelengths that are as small as 100000 times that of visible light can be seen. This helps an electron microscope to reveal very minute details. Electron microscopes are commonly used in biology labs to study microscopic organisms such as bacteria and viruses.  

Conclusion 

Matter waves form the foundation of quantum physics. They are based on the fact that everything in the universe exhibits both wave nature as well as particle nature. This concept was first given by French physicist Louis de Broglie in 1924. Therefore they’re also referred to as the de Broglie waves. The de Broglie wavelength is represented by the following relation- 

λ= h/p = h/mv

Here, λ represents the wavelength of the particle, h is the Planck’s constant and mv=p is the momentum. 

The de Broglie hypothesis is responsible for the appearance of subatomic particles at unexpected sites because their waves penetrate through the barriers. 

The de Broglie hypothesis has various applications in our life. It helps in determining the probability of finding any particle in the configuration space. It is also used in the construction of an electron microscope. These are popularly used in biology labs to study microscopic organisms like bacteria, viruses etc.