Lasers, qubits and a revolutionary quantum computer

4 Aug 2016

Close-up photo of an ion trap, image via S. Debnath and E. Edwards/JQI

The new dawn of computers has never been nearer, with a fully-programmable quantum computer, relying on laser-controlled qubits, turning heads in the industry.

Taking advantage of the unique properties offered by trapped ions (qubits), and operated by a series of lasers, a new quantum computer from the University of Maryland is turning heads in the world of computing.

This is a big deal because quantum computing is so much more powerful than current forms of computing.

Problem-solving through quantum computing is theoretically so fast that modest versions could render today’s supercomputers relatively insignificant.

Quantum computing


This quantum computer module (it can be added to, so is considered somewhat modular) sports just five qubits at the moment, but the fact that it has been created and tested could prove the eventual death knell for the supercomputer.

While previous attempts to show quantum computers were limited to fixed-pattern interactions under the hood, according to the research team, this latest creation is a “fully programmable and reconfigurable quantum computer”.

“By directly connecting any pair of qubits, we can reconfigure the system to implement any algorithm,” said Shantanu Debnath, lead author on the research paper now published in Nature.

“While it’s just five qubits, we know how to apply the same technique to much larger collections,” said Debnath, who is a graduate student at the Joint Quantum Institute and the Joint Centre for Quantum Information and Computer Science at the University of Maryland.

The way the computer works is through the manipulation of qubits, with magnetic fields holding them so tightly together that they can vibrate in a coherent manner – the vibration comes from targeted lasers, each of different colours.

This produces a quantum entanglement, rendering each separate unit indistinguishable from another, meaning they can be in more than one state at the same time and, thus, quantum compute.


In the past, IBM and Google have shown their cards in this area, with the future of data storage, security and everything in between potentially at the mercy of a quantum computing revolution.

Rather than using conventional bits seen in the computers and phones we use in our everyday lives, which work off the binary system of ones and zeroes, a qubit has the added ability to be a one, zero or both.

With this, its ability to speed through problem solving is simply unmatched when compared to conventional binary computers.

The qubits are constantly controlled by laser pulses, which Debnath says “becomes a software problem”, something no previous quantum computing architecture can replicate.

A series of programs were run to show the computer’s power, such as encryption-cracking processes and other problem-solving activities.

The next stage is upping the qubit levels, which the researchers claim is very doable.

Gordon Hunt was a journalist with Silicon Republic