Quantum computing has the potential to easily crack current cryptography systems, simulate chemical and nanochemical quantum systems, and speed up the search for solutions of certain types of math problems called NP Complete problems. Many have raced to create the world's first quantum processor.
In 2007 D-Wave, a Canadian firm, claimed to have created the world's first quantum computing chip. Debate about whether the chip is a true quantum computer has raged, while the company has continued to release claims of improved "quantum chips" -- with the latest being a 128 qubit chip. Researchers, though, are skeptical of these claims.
Now, researchers at Yale University claim that they have created the world's first solid state quantum processor. The new chip, at the very least is the first processor to be officially reported in a peer-reviewed journal. The research appears in the journal Nature's June 28 advanced publication listing.
The chip is composed of 2 qubits ("quantum bits"). Each qubit is composed of billions of aluminum atoms. Qubits are different than traditional bits, in that while they can hold a value of one or zero, they can also hold a superposition of both states. Essentially, this means that the two qubit chip can hold 4 simultaneous states, while a 2 bit chip could only hold 1 state (with four possibilities).
Thus the use of qubits enables multiple tests with a single value. For example if you had four phone numbers and one belonged to your friend a traditional processor would typically require a call to a couple of numbers before the correct one was found. According to Yale Professor of Applied Physics and Physics Robert Schoelkopf, "Instead of having to place a phone call to one number, then another number, you use quantum mechanics to speed up the process. It's like being able to place one phone call that simultaneously tests all four numbers, but only goes through to the right one."
The researchers used the new chip to run elementary algorithms, such as a simple search, based on this concept. States Professor Schoelkopf, "Our processor can perform only a few very simple quantum tasks, which have been demonstrated before with single nuclei, atoms and photons. But this is the first time they've been possible in an all-electronic device that looks and feels much more like a regular microprocessor."
The qubit processor communicates via a "quantum bus" which sends signals by photons. The key breakthrough that allowed the creation of the chip, according to the team, was the ability to fix atoms in a specific quantum state for longer. When qubits were first manipulated a decade ago, they would only last up to a nanosecond -- the Yale team got them to last for a microsecond, long enough for computing purposes.
The Yale researchers look forward to prolonging the states even further, to allow more complex algorithms. They also hope to add more qubits to their design. The team writes that scientists are "far away" from a practical quantum computer, still, though. And in laying claim to the world's "first" quantum computer chip, they're essentially throwing down the gauntlet with D-Wave, effectively accusing them of peddling snake oil to the corporate world.
quote: Schrödinger's cat is both dead and alive before you check, but after you check the cat is either dead or alive.