Quantum computing: new methods for removing error

From ScienceDaily:

Researchers at the National Institute of Standards and Technology (NIST) have demonstrated a technique for efficiently suppressing errors in quantum computers. The advance could eventually make it much easier to build useful versions of these potentially powerful but highly fragile machines, which theoretically could solve important problems that are intractable using today’s computers.

The new error-suppression method was demonstrated using an array of about 1,000 ultracold beryllium ions (electrically charged atoms) trapped by electric and magnetic fields.

The NIST method is an adaptation of “spin echo” techniques used for decades to suppress errors in nuclear magnetic resonance (the basis of magnetic resonance imaging). In spin echo, evenly spaced control pulses will nearly reverse the buildup of error, as long as fluctuations are slow relative to the time between pulses.