There has been a lot of buzz about Quantum Computers as of recent. Tech Giants like IBM and Microsoft racing to harness the power of Quantum Mechanics in order to make machines that have incredible computing power. But, the idea of Quantum Computing has been around since the 1980s, the question arises why then, the sudden interest in an idea that is more than three decades old?

From the time computers have existed, they have played an integral role in our scientific advancements. It wouldn’t be a stretch to say that our technological progress is closely tied with our computing machines. So when our trusted computing machines reached their limits, this posed a very real problem for our advancements in all fields of science.

From Big To Small

Let’s take a little trip down memory lane, of the history of computers. Electronic Numerical Integrator And Computer or ENIAC for short was the world’s first fully functional computer, it was created around the end of 1945, and it was a huge machine. It spanned over a surface of 1,800 square feet and weighed 30 tons, filling a 50 foot long basement with ease.

This monster of a machine was the world’s first glimpse at a modern day computer. Computers from the time they were invented have been progressively growing, I mean shrinking smaller and smaller in size. Today your computing device can easily fit into the pocket of your pants, or in your backpack. But just how is this shrinking in size possible? And is it necessary?

Building Block of Technology

Essentially, the brain of a computer is a bunch of switches and wires that can be flipped on and off controlling the flow of electricity - these switches are called transistors. Without getting into the specifics of it, a group of transistors working in combinations is what gives the computer its ‘logic’.

A bunch of transistors together make a circuit board – when circuit boards became smaller we started calling them chips. These transistors are vital and is the brains behind the computer, the computers of yesteryear were as big as a room because the transistors of that time were equally huge. The more transistors we can fit in a smaller patch of area, the ‘smarter’ a computer gets.

Chips host a large number of transistors, a chip the size of your fingertip can house almost 4.3 billion transistors! We can achieve this by making our transistors extremely small, right now the smallest one we have is just 1 nanometer big. This is where the problem lies because we are almost at the size of atoms (Atomic Range) which is between 0.1 to 0.5 nanometers.

The Limitation

Remember our previous point that transistors are essentially switches that either allow or stop the flow or electricity through them, electricity in other words is the flow of electrons. When we start approaching the atomic range (0.1 nm – 0.5 nm), electrons start to disobey the laws of physics that we know and understand.

The situation now is subject to ‘Quantum Physics’ which is a different branch of physics with its own rules that apply in the ‘Quantum Realm’. Due to a phenomenon called ‘Quantum Tunneling’ some electrons will bafflingly disappear from one side and reappear on the other side. Our systems are dependent on the transistors being perfectly functional, that is - either completely stopping the flow of electricity or letting it through.

Size Matters

If we go any smaller than 1 nanometer when making our transistor, our transistors will fail to function properly. This in turn limits how many transistors we can fit in a small area, which ultimately prevents us from increasing our computing power in conventional computers.

Without breakthroughs in Quantum Computing, we may be held back from progressing in other fields of science. It is for this very reason that scientists are pushing to create a working Quantum Computer that they can count on, a computer that can harness the weird Quantum Mechanics to its advantage and carry us to new heights.