An international group of scientists (Researchers are finding ways to improve the storage time of quantum information in rich matter) has made further progress in securing the unity of quantum dot spin qubits as part of a global push for practical quantum networks and quantum computers.
These technologies will change many companies and research efforts: from the security of information transmission, to the search for materials and chemicals with novel properties, and the measurement of basic physical activities that require time synchronization.
Spin-photon interfaces are the first building blocks for quantum networks that convert represented quantum information (such as the quantum state of an ion or a solid state spin qubit) into light, i.e. photons, which can be transmitted n ‘far away. The big challenge is to find an interface that is efficient in storing quantum information and efficient in converting it to light. Optically active semiconductor dots are the most efficient spin-photon interface known to date, but extending their storage time beyond microseconds has vexed scientists despite a decades-long research effort. Now, researchers from the University of Cambridge, the University of Linz and the University of Sheffield have shown that there is a simple hardware solution to this problem that enables the storage of quantum information beyond hundreds of microseconds.
A quantum dot is a crystalline structure made up of thousands of atoms. Each of these three holes has a magnetic dipole moment that couples into the quantum dot electron and can cause the loss of quantum information stored in the electron qubit. The research team’s findings, reported in Nature Nanotechnology, is that in semiconductor devices with a single lattice structure, the nuclei “feel” the same environment and interact with each other.
As a result, it is now possible to eliminate this nuclear noise and achieve an improvement of almost two orders of magnitude in terms of safety. “This is a new method for a highly functional quantum dot where we can turn off its interactions with its internals and re-tweak the spin of the electron over and over again to bring its quantum state back to life,” said Claire. Claire said. Le Gall of the Cavendish Laboratory. in Cambridge, who directed the project.
“We have demonstrated hundreds of microseconds in our work, but of course, now that we are in this government, we know that the unity time is much longer. For point-to-point conversion, short connection time is the biggest limitation in applications, and this research provides a clear and simple solution for that.
Searching for a period of hundreds of microseconds for the first time, the researchers were happy to find that the electron only sees the sound from the nuclei, as opposed to, for example, the electrical sound in the device. This is really a big situation because the nuclear fusion is an isolated quantum process and the electron binding together will be the gateway to the quantum phenomena in the nuclear fusion. Another thing that surprised the researchers was the “sound” that the nuclei carry.
It is not as smooth as originally expected, but there is an opportunity to improve the unity of the system by using other materials engineering. “When we started to work on the system of materials and networks used for this work, getting quantum dots and objects that are well defined and good optics is not easy” – Armando Rastelli, author of this paper at the University University, explains. Linz. “It is gratifying to see that the first research process of curiosity in the ‘different’ process and the perseverance of the teammates Santanu Manna and Saimon Covre da Silva has led to tools that cause results these people are awesome. Now we know what nanostructures we use and we are excited about the prospect of further developing their properties with us.
“One of the most exciting things about this research is the computational complexity of the system: hundreds of thousands of nuclei are connected to a well-controlled electronic machine,” said Cavendish PhD student Leon Zaporski. says the first author of the book. . “Many researchers approach the problem of isolating qubits from noise by removing all interactions. The qubits are like Schrödinger’s cats, which can react to anyone pulling their tail. “Cat” we take things exciting, which in practice means that we can have more fun with them.
“The quantum dot now combines high photon quantum efficiency with long coupling times,” explains co-author Professor Mete Atatüre. “In the near future, we hope that these devices help to create the light conditions for full photonic quantum computing and make the necessary numbers.
