A molecular two-qubit architecture could help edge scientists closer to practical quantum computing
A multidisciplinary team of scientists in Italy has designed a fast-switching, highly coherent molecular two-qubit gate combining nuclear and electronic spins for quantum logic operations.1
Quantum information processing uses quantum phenomena, like quantum superposition and entanglement, to encode information. Quantum bits, or qubits, are the building blocks of quantum information processing, much as classical ‘bits’ are for current computers. Like bits, qubits carry information, but, unlike bits, qubits can exist simultaneously in multiple states – known as superposition. This allows for faster and more complicated information processing. The problem is that maintaining this state is hard. Noise from the outside environment, or even from lattice vibrations within the molecule itself, can cause decoherence, and the irreversible destruction of the information that the qubit carries. The time a qubit can maintain this quantum superposition – its coherence – depends on the material or molecule used and its environment. Lower temperatures decrease noise, so current quantum computers run at temperatures close to absolute zero.