Погляд художника на заплутане лазерне світло з біжучою звуковою хвилею в інтегрованому фотонному хвилеводі / Олександра Дженес, MPI
Scientists have created quantum entanglement of the smallest particles of light and sound waves. The resistance of the formed connection to external noise is important for quantum computers.
Physicists from the Max Planck Institute have discovered a way to entangle particles of different types: a unit of light (photon) with the quantum equivalent of a sound wave (phonon). Chanlong Zhu, Claudiu Genes, and Birgit Stiller named this system opto-acoustic entanglement.
This hybrid system is uniquely resistant to external noise, which is one of the biggest problems faced by quantum technology. The new connection is a significant step towards more reliable quantum computers. Normally, the quantum state needed for computations can be easily disturbed—this factor limits the development of quantum devices.
Scientists are working on solving this problem, having several promising avenues. Higher dimensions reduce the impact of negative noise, as does adding more particles to the entangled system. Likely, a practical solution will use more than one approach, so each additional technology becomes a significant contribution to solving the problem.
Opto-acoustic entanglement is quite difficult to achieve since photons and phonons move at different speeds and have different energy levels. Researchers used a process called Brillouin scattering, whereby light is scattered among the atoms of a material by sound waves created by heat.
In the system proposed by the scientists, laser light and acoustic waves were transmitted into a built-in solid-state waveguide, designed to create Brillouin scattering. As the two quanta move along a single photonic structure, the phonon moves at a significantly lower speed, leading to scattering that can entangle particles with radically different energy levels.
“The fact that the system operates across a broad range of both optical and acoustic modes opens up a new perspective of bonding with continuous modes with great potential for applications in quantum computing, quantum memory, quantum metrology, quantum teleportation, and quantum communication through entanglement, as well as for research at the boundary between the classical and quantum worlds,” states the study.
What’s fascinating about the technology is that entanglement is achieved at higher temperatures than other methods allow. Thus, entanglement is moved out of the cryogenic zone and potentially reduces the need for expensive cooling. This method is further research and experiments, but it is a highly promising result, say scientists. The study is published in Physical Review Letters.
Source: Science Alert