Researchers have designed a device that could one day form the building blocks of quantum information processing systems by carefully placing a tiny piece of diamond within a few nanometers of a carbon nanotube, and then sending an electric current through said nanotube.
In their recent study, they have shown that the electrified nanotube's mechanical vibrations couple to the magnetic (or spin) properties of defects in the diamond. This coupling allows for the quantum states of the nanotube and diamond to be transferred to each other as well as to a second diamond positioned several micrometers away.
The researchers, Peng-Bo Li et al., have published a paper on the new hybrid quantum device in a recent issue of Physical Review Letters.
Diamonds and carbon nanotubes, which are both carbon allotropes, each have their own unique properties that make building such a device possible.
Diamond contains defects called nitrogen-vacancy centers that emit highly coherent bright red light. The defects' optical properties can be well-controlled so that they occupy one of two distinct states, which enables the defects to act as qubits.
Carbon nanotubes, for their part, are well-known for their highly advantageous mechanical and electrical properties.
Both diamonds and carbon nanotubes have been widely studied as separate entities, but rarely together as an integrated device.
"This device could be used to mechanically address quantum logic gates based on electric spins and could serve as novel nanoscale sensors for detecting tiny pressure, temperature, electric, and magnetic-field changes in the physical and life sciences," Li said.