Quantum information is fragile and often difficult to protect during experiments. Protecting qubits from accidental measurements is essential for controlled quantum operations, especially during state-destroying measurements or resets on adjacent qubits in protocols like quantum error correction. Current methods to preserve atomic qubits against disturbances can waste coherence time, extra qubits, and introduce errors.
University of Waterloo researchers have successfully demonstrated the ability to measure and reset a trapped ion qubit to a known state without disturbing neighbouring qubits just a few micrometres away - a distance smaller than the width of a human hair, which is about 100 micrometres thick.
The demonstration has the potential to significantly impact future research in the field, including advancing quantum processors, enhancing speed and capabilities for tasks like quantum simulations in machines that already exist today, and in implementing error correction.
Rajibul Islam
This breakthrough was achieved by a team led by Rajibul Islam, a faculty member at the Institute for Quantum Computing (IQC) and professor in the Department of Physics and Astronomy, along with postdoctoral fellow Sainath Motlakunta and students in their research group.
By precisely controlling the laser light used in these operations, they overcame what was once considered an impossible challenge: protecting qubits while measuring others at such close distances.
