Korean Scientists Achieve Unprecedented Real-Time Capture of Quantum Information

By Daegu Gyeongbuk Institute of Science and Technology (DGIST) November 20, 2024

Collected at: https://scitechdaily.com/korean-scientists-achieve-unprecedented-real-time-capture-of-quantum-information/

DGIST and UNIST researchers have discovered a new quantum state, the exciton-Floquet synthesis state, enabling real-time quantum information control in two-dimensional semiconductors.

A research team led by Professor Jaedong Lee from the Department of Chemical Physics at DGIST (President Kunwoo Lee) has unveiled a groundbreaking quantum state and an innovative mechanism for extracting and manipulating quantum information through exciton and Floquet states.

Collaborating with Professor Noejung Park from UNIST’s Department of Physics (President Chongrae Park), the team has, for the first time, demonstrated the formation and synthesis process of exciton and Floquet states, which arise from light-matter interactions in two-dimensional semiconductors. This study captures quantum information in real-time as it unfolds through entanglement, offering valuable insights into the exciton formation process in these materials, thereby advancing quantum information technology.

Advantages of Two-Dimensional Semiconductors

Unlike traditional three-dimensional solids, where quantum coherence is challenging to maintain owing to thermal influences, two-dimensional semiconductors feature energy levels for excitons and conduction bands that remain distinct owing to weaker screening effects, thus preserving coherence over extended periods. This distinction makes two-dimensional semiconductors promising for developing quantum information devices. Yet, until now, the coherence and decoherence mechanisms of electrons during exciton formation have been poorly understood.

Through theoretical calculations using time-resolved angular-resolved photoelectron spectroscopy on two-dimensional semiconductor materials, Professor Lee’s team confirmed that exciton formation coincides with the creation of a Floquet state, producing a combined new quantum state. Additionally, they identified the mechanism by which quantum entanglement occurs within this state and proposed a real-time method to extract, unfold, and control quantum information.

Professor Jaedong Lee, of DGIST’s Department of Chemical Physics, commented, “We have discovered a new quantum state, known as the exciton-Floquet synthesis state, and proposed a novel mechanism for quantum entanglement and quantum information extraction. This is anticipated to drive forward quantum information technology research in two-dimensional semiconductors.” UNIST’s Professor Noejung Park added, “This research sets a new paradigm for quantum information technology, including quantum computers, marking an important milestone for its realization.”

Reference: “Novel Quantum States of Exciton–Floquet Composites: Electron–Hole Entanglement and Information” by Hyosub Park, Noejung Park and JaeDong Lee, 9 October 2024, Nano Letters.
DOI: 10.1021/acs.nanolett.4c03100