Carbon nanotubes could make longer duration qubits for quantum memory in future quantum computers

Researchers from Delft University of Technology studied how decoherence could be measured in mechanical resonators, basically tiny vibrating strings made from carbon nanotubes, and found that the processes of decoherence in a vibrating nanotube can be thought of in a very similar way as the decoherence of a quantum bit. Using this similarity, you can visualize the loss of quantum information by thinking about a vibrating guitar string.

Nanostrings

Avoiding decoherence is the key to building a working quantum computer. As this decoherence is caused by random movements of matter surrounding qubits, qubits are usually operated at extremely low temperatures to keep their environment as quiet as possible. Potentially, quantum information can also be stored in nanostrings: miniscule vibrating carbon nanotubes. Because the nanotubes are so small and light, they are a sensitive tool for learning about mechanical decoherence. An important question is if mechanical quantum resonators could preserve quantum information for a much longer period than qubits. If they could, then they could be used as a ‘quantum memory’ in future quantum computers.


The nanostring is visible as a thin white line on this elecron microscope image

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