Quantum Computers Are Amazing By Katherine Lightwood

Quantum Computers Are Amazing

By Katherine Lightwood 

Two days ago my wonderful colleague Praveen shared an article with me about Quantum computer and it's recent development and it just amazed me.

Today in the evening when everyone went out to a party thrown by my another colleague about her win in a competition, I sat down and started reading an article on the same topic. Although it was a bit old one but it was new for me. Now, let me make you understand what a quantum computer is in a layman's language.

A classical computer performs operations using classical bits, which can either be zero or one. Now, in contrast, a quantum computer uses quantum bits or qubits. And they can be both zero and one at the same time. and this is this, that gives a quantum computer it's superior computing power. There are a number of physical objects that can be used as qubits. A single photon, a nucleus or an electron.

In this research paper where scientists were using the outermost electron of phosphorus as a qubit. But I wondered how does this work? Well!! As you know all electrons have a magnetic field, so they are basically like tiny bar magnets. And this property is called spin If you place them in a magnetic field, they will align with that field just like a compass needle lines up with the magnetic field of the earth.

Here, the lowest energy state of the electron is called spin down. Now, you can put it in one state or spin up but that will take some energy. So far this is basically like the classical bit. IT got two states spin up and spin down which are like the classical 'one and zero'. But a strange thing about a quantum object is that they can be in both states at once. Now, when you measure the spin it can be either up or down.But before you measure it the electron can exist in what is called a quantum superposition where you have the possibility to find the electron in one state or the other. Now, it's hard to imagine how these enable this incredible computing power of quantum computers without considering two interacting quantum bits.

So, there are four possible states of these two electrons. Quantum mechanics allows us to make a superposition of each one of these possible states. But here's the twist, although the qubits can exist in any combination of states when they are measured they must fall into one of the basis states. And all the other information about the state before the measurement is lost.

But behold!! My friends, quantum computers cannot ever replace classical computers because they are only faster for special kinds of calculations where you can use the fact that you have all the quantum superposition available to you at the same time to do some kind of computational parallelism. If you just want to watch a video on your computer in high details or browse the internet or write some documenting work they are not going to give you any particular improvement. You need to use a classical algorithm to get the results. So, we shouldn't think of quantum computers as something where every operation is faster in fact operations might be slower instead.

So, that was my thought of the day. To see more posts like this make sure to visit our main page. And do not forget to visit our institute's page to know more about graphic design, 3D, animation courses and other awesome stuff. Till then good day to you.

Katherine Lightwood