2023/12/12 by Wan-Guan Chang, Chang, Wan-Guan, Chia-Yi Ju +7 · 3 citations
Computer Science · Engineering · #Advanced Memory and Neural Computing #FOS: Physical sciences #Neural Networks and Applications #Neural Networks and Reservoir Computing #Quantum Physics (quant-ph)
paper · pdf · doi:10.48550/arxiv.2312.06939
openalex publication_date 2023/12/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
To store quantum information, quantum memory plays a central intermediate ingredient in a network. The minimal criterion for a reliable quantum memory is the maintenance of the entangled state, which can be described by the non-entanglement-breaking (non-EB) channel. In this work, we show that all single-qubit quantum memory can be quantified without trusting input state generation. In other words, we provide a semi-device-independent approach to quantify all single-qubit quantum memory. More specifically, we apply the concept of the two-qubit quantum steering ellipsoids to a single-qubit quantum channel and define the channel ellipsoids. An ellipsoid can be constructed by visualizing finite output states within the Bloch sphere. Since the Choi-Jamiołkowski state of a channel can all be reconstructed from geometric data of the channel ellipsoid, a reliable quantum memory can be detected. Finally, we visually quantify the single-qubit quantum memory by observing the volume of the channel ellipsoid.