We’re Close to a Universal Quantum Computer, Here’s Where We're At

What you’re looking at is a hermetically sealed glass laboratory. Scientists here are engineering special chips that could power the next computing revolution: a universal quantum computer. Chances are you’ve heard of quantum computer and that they’re going to change everything.

Quantum computer are new kinds of machines that promise an exponential growth spurt in processing power, capable of tackling problems our computers today can’t solve. While an encryption busting/global problem solving quantum computer doesn’t exist yet, the field has gained some serious momentum.

According to Andrew Bestwick, Director of Engineering at Rigetti Computing, “we've reached a point where it's pretty clear that those performance numbers are good enough now you could build a real product, a real piece of technology out of this idea. When that threshold got crossed, people started to place their bets.”

Tech giants like IBM and Google, and startups like Rigetti Computing are all in something of a scientific race to building the first universal quantum computer. But to understand what makes a quantum computer so uniquely powerful, you’ll need to know a bit about quantum mechanics.

“Quantum mechanics is the field that describes the simplest things around us, individual electrons or atoms, or particles of light like photons. The fascinating thing is, when you look at these very simple systems, they don’t really obey the same rules that the world around us does. We use sort of two very important properties of quantum mechanics. One of them is superposition of states and the other one is entanglement.”

“When we talk about classical computing, we often hear the word ‘bit’ and bit can refer to 0 or 1. You can also think it as a binary state. You have a switch, it can be on or it can be off," says Jerry Chow, Manager of IBM's Experimental Quantum Computing Group. 

For instance, when you’re physically typing commands into your computer to write an email, each letter you strike on the keyboard is translated to a unique string of 0s and 1s that are being switched on and off to digitally represent your words.

But with superposition, quantum computer can do things differently.

Alexa Staley, Quantum Engineer at Rigetti Computing explains: "Instead of using these bits, these zeros or ones, we use what’s called qubits, which are quantum bits and these bits instead of being a zero or a one, can either be any combination of a zero and a one… This is something that arises because of quantum mechanics and allows us to do more tricks.”

But controlling qubits and constructing the right quantum architecture are today’s major engineering challenges which is why quantum computers and the labs that house them today, look like a jumble of wires and cables. 

“It's right where computers were in the '50s or '40s….where you had technicians plugging and unplugging things all over the place on some wall of electronics. You want things when you're first building them to be really modular and reconfigurable,” says Bestwick. 

In a head to head match between quantum computers and classical computers today, our laptops still dominate, at least for now.

“Today's quantum computers aren't big enough or high-performing enough to actually do something better than a classical computer. That's going to change pretty soon. An example of this is, it is impossible for a computer to anticipate what a molecule would do in the human body, right? This is something that the drug development industry has to spend billions of dollars figuring out by just guessing and checking. Nature doesn't store information in zeros and ones. The operating system of nature is quantum mechanics. If you want to simulate a quantum system, you need something that can do it quantum mechanically. That's the kind of problem that a quantum computer can solve. “

Because quantum computers can analyze large quantities of data & spot patterns quickly, they could tackle optimization problems for transportation and industry, advance climate modeling, and boost artificial intelligence research one day.