As we all know digital electronic computers are based on transistors. They are built with complex circuit systems which consist with registers, logic gates etc. Conventional computing is used for normal calculations. In digital computing, data is encoded into binary digits which is called bits (1 or 0). So, it can take combinations as below once at a time.
What is Quantum Tunnelling?
According to classical mechanics it’s impossible for a particle to move through a barrier because of the insufficient energy to overcome the barrier. Bur according to the quantum world particle behaves like waves. The below image shows it clearly. This effect of quantum tunnelling and the uncertainty principle lead to quantum computing.
Registers, logic gates and bits are the conventional features in ordinary computer. But in quantum computer has quantum bits which are also called “Qubits”. It can store either 0 or 1 or a value in between them. In other words, it can store multiple values at the same time. This concept is called quantum superposition.
Now what is superposition?
When two waves meet, they overlap each other. Because of this the output wave can be either bigger or cancel each other. This phenomenon is known as superposition.
What is Quantum Superposition?
Quantum system can be existed in various states at the same time. For example, an electron has two possible states referred to as spin up and spin down in the presence of a magnetic field. So, in a magnetic field it shows both states at the same time. But when it measured it shows a specific spin state. So how it happens? An Austrian physicist Erwin Schrödinger explains this using his Schrödinger’s cat experiment
Hope you get an idea about Quantum Computing.
Now for what Quantum Computing is for?
This can be used for parallel processing because of the superposition feature. This is also used for brute force the encrypted codes. If we use conventional computers for brute forcing it takes centuries to complete it. By quantum computing it reduces the time duration. But he main thing is quantum computers are only used to solve complex scenarios. And there is also a quantum computing company named “D-Wave”.
Hope you get an idea about Quantum Computing. Thank You !!!