Light pulses put a new "spin" on quantum supercomputing: The paper, "Quantum Computers Based on Electron Spins Controlled by Ultrafast Off-Resonant Single Optical Pulses," details a scheme to create one of the fastest quantum computers to date by using light pulses to rotate electron spins which serve as quantum bits. This technique improves the overall clock rate of the quantum computer. The researchers combined fast single-bit rotations and fast two-qubit gates (both optically controlled) on a single chip. The chip consists of a loop of cavities (called a "loop-qubus") -- each cavity holds a quantum dot, a small piece of semiconductor that contains a single electron. When you focus an optical pulse at a quantum dot, the electron spins rotate, changing the state of the bit. Very detailed piece of work.
Faster than a speeding bullet: Is light key to quantum supercomputing?