To build a quantum computer, scientists first have to build a working qubit, or quantum bit, that is both controllable and measurable (something that, for few very quantum reasons, is fairly challenging). But a group of Harvard physicists have overcome some key obstacles to turn the impurities in lab-grown diamonds into quantum bits capable of holding information at room temperature for nearly two seconds--an eternity in quantum coherence times.
Silicon semiconductors have taken us a dazzling distance along the computing road. But even if they continue unabated to get faster and more powerful (and it's growing more difficult to make that happen) there's a limit to what classical computing can do.
The next real game-change in computing is quantum--tapping the quantum mechanical properties of materials to process information in ways that will make today's biggest and baddest super computers look like pocket calculators. And for the first time scientists, at places like IBM, are moving beyond just theorizing about them to actually envisioning how a finished quantum computer would work. In labs across the globe, the first building blocks of the first quantum computers are slowly becoming real.
That's huge considering a working quantum computer would be the kind of thing that truly moves the ground beneath our feet. With a relatively modest quantum computer, scientists could slice through sophisticated encryption schemes, model quantum systems with unprecedented accuracy, and filter through complex, unstructured databases with unparalleled efficiency.
But first they have to build one.
When quantum computers eventually reach larger scales, they'll probably remain pretty precious resources, locked away in research institutions just like our classical supercomputers. So anyone who wants to perform quantum calculations will likely have to do it in the cloud, remotely accessing a quantum server somewhere else.
Vancouver-based quantum computer maker D-Wave Systems is the kind of company that often gets mixed reviews--either kudos for working on the very edge of a new and potentially groundbreaking technology, or dismissal for not exactly delivering the kind of Earth-shattering technology that people were perhaps expecting. Regardless, today D-Wave is marking one in the win column after announcing that it has achieved the world’s largest quantum computation using 84 qubits.
James Gleick asks: as scientists crunch and quantize the world, will they ever reach the end?
By James GleickPosted 11.01.2011 at 3:40 pm 25 Comments
A countryman came into a telegraph office in Bangor, Maine, with a message, and asked that it be sent immediately. The operator took the message as usual, put his instrument in communication with its destination, ticked off the signals upon the key, and then, according to the rule of the office, hung the message paper on the hook with others that had been previously sent. ... The man lounged around some time, evidently unsatisfied. "At last," says the narrator of the incident, "his patience was exhausted, and he belched out, 'Ain't you going to send that dispatch?'" The operator politely informed him that he had sent it. "No, yer ain't," replied the indignant man; "there it is now on the hook."—Harper's New Monthly Magazine, 1873
Researchers on two continents are reporting two big breakthroughs in quantum computing today — a quantum system built on the familiar von Neumann processor-memory architecture, and a working digital quantum simulator built on a quantum-computer platform. Although these developments are still constrained to the lab, they’re yet another sign that a quantum leap in computing may be just around the corner.
Is this the beginning of the quantum Internet? UK researchers have shown that quantum and classical data streams can be interwoven within traditional fiber optics networks, enabling the distribution of quantum information to the home on existing cable. That means quantum key distribution (QKD) can work alongside traditional, classical data channels, a development that essentially lays the groundwork for a quantum Internet that exists alongside the classical one we have now.
Physicists have stored information for nearly two minutes inside the magnetic spins of atomic nuclei, producing the longest-lasting spintronic device yet and what could be the world’s tiniest computer memory.
There’s just one problem: the computer operates at -454 F (about 3.2 degrees K) and requires a magnetic field roughly 200,000 times more powerful than Earth’s.