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UCSB Researchers Working on New Quantum Computer

Could Provide Framework for Revolutionizing Data-Encryption Process


Sunday, August 26, 2012

While it currently operates at a the level of a below-average 4th grader, a new quantum computer designed by researchers at UCSB may provide the framework for revolutionizing the data-encryption process.

Researchers at UCSB have designed a quantum computer capable of factoring numbers into their primes — an integral part of cryptography and cyber security, according to the researchers’ recent paper in Nature Physics. While its future implications are great, the project is in its fledgling stages; during 150,000 trials, UCSB’s first quantum processor succeeded in correctly determining that 15 factored into 3 times 5 approximately half of the time.

Although one out of two is a measly success rate even for a slide rule, the solid-state quantum processor is running a version of Peter Shor’s prime factoring algorithm, a complex mathematical process for breaking down numbers that, in theory, is correct exactly 50 percent of the time.

As it happens, determining the prime factors of the number 15 is not a bad starting point. With some refinements, and applied on a bigger scale in a bigger machine, the quantum processor could be capable of deciphering even the largest of numbers, like the 600-digit-plus strings sometimes used in RSA encryption, the most prevalent form of data encoding. According to Erik Lucero, lead author of the researchers’ paper, a standard computer and classical algorithms could factor the RSA Laboratory’s largest number — but it would take longer than the age of the universe to do so. An appropriately large quantum computer armed with Shor’s algorithm, Lucero says, could crack that number in a matter of minutes. Lucero, a former doctoral student in physics at UCSB, is now an experimental quantum computing researcher at IBM.

If such a processor enters the market, traditional encrypting will be forced to change completely. According to Lucero, the quantum processors power can be used for both sides of the process, allowing “quantum cryptography” to replace traditional RSA. Quantum encrypting would be more difficult to crack and far easier to keep secure — Lucero says quantum cryptography systems immediately notify both user and potential intruder when the system has been tampered with. For example, Lucero said a voice conversation over quantum encrypted lines would immediately become “jumbled” when a third party attempted to access the system.

For now, the researchers’ tests have shown that their theory and design are sound, and the quantum computer has the potential to crack harder numbers better, faster, and stronger than any system before it.