There cosmic radiation can be cause errors by quantum computersfor this reason scientists want to investigate and, if possible, solve the problem using a mine located 2 kilometers below the earth’s surface.
This is what the researchers will do Chalmers University of Technology (Sweden) and University of Waterloo (Canada). “Radiation from space represents a challenge for quantum computers, whose calculation time is limited by cosmic rays”, explain the scientists, “which is why we will go deep in search of a solution to this problem”.
The Canadian underground laboratory SNOLAB, an ideal location for research in quantum technology as it is located 2 kilometers underground
Highly charged particles coming from space disturb sensitive qubits, leading them to lose their quantum state, as well as the ability to continue performing a calculation. For this reason the researchers will go to the deepest clean room in the world, two kilometers underground.
“We are excited about this project because it addresses the very important question of how cosmic radiation affects qubits and quantum processors. Gaining access to this underground facility is critical to understand how to mitigate the effects of cosmic radiation“, said Per Delsing, professor of quantum technology at Chalmers University of Technology and director of the Wallenberg Center for Quantum Technology.
The unique research project is a collaboration between researchers at Chalmers University of Technology, the Institute for Quantum Computing (IQC) at the University of Waterloo and SNOLAB near Sudbury, Ontario, also in Canada.
In the study, superconducting qubits produced by Chalmers University of Technology will be first tested on the surface both in Sweden and Canada. Subsequently, the qubits themselves will be tested deep beneath Canadian soilso you can study the differences between the two environments. With the help of the two-kilometer-thick “earth shield” surrounding the clean room, located at the Vales Creighton mine in Ontario, researchers they will be able to exclude cosmic rays or radioactivity which would otherwise have “knocked out” the qubits on the surface.
“SNOLAB maintains the lowest muon flux (particles that form when cosmic rays reach the Earth’s atmosphere, ed.) in the world and has advanced cryogenic testing capabilities, making it an ideal location to conduct valuable research into quantum technologies,” said Jeter Hall, director of research at SNOLAB and adjunct professor at Laurentian University in Canada.
For quantum computers to have a real impact, researchers must first solve the problem of error correction. Where traditional computers use systems that can correct errors that occur and provide reliable results, there are currently no systems powerful enough to correct the significantly more complex errors that occur in quantum computers.
“Error correction methods used in quantum computers today assume that each error caused by cosmic rays occurs independently of each other,” we read in a press release. “This is an incorrect assessment, since these types of errors, on the contrary, are usually correlated between them”.
Current error correction methods are unable to correct related errors, meaning that multiple qubits can lose their quantum state at the same time. By increasing our understanding of qubit processes, we want to find ways to reduce the number of related errors.
“With this project we hope to begin to understand what happens with qubit decoherence in relation to cosmic raysand then understand how radiation affects qubits in more controlled ways,” said Dr. Chris Wilson, a professor at the University of Waterloo.
