Organizer：

Jin-Peng Liu 刘锦鹏（YMSC）

Speaker：

Fuchuan Wei 魏付川 （YMSC）

Time：

Wed., 10:30-11:30 am, Sept. 17, 2025

Venue：

Ningzhai 宁斋 203

Online：

腾讯会议/Voov: 963-193-309

Title:

BELT: Block Encoding of Linear Transformation on Density Matrices

Abstract:

Linear maps that are not completely positive play a crucial role in the study of quantum information, yet their non-completely positive nature renders them challenging to realize physically. We introduce Block Encoding of Linear Transformation (BELT), a systematic protocol that simulates arbitrary linear maps by embedding the output $\mathcal{N}(\rho)$ into a block of a unitary operator. BELT enables the manipulation and extraction of information about $\mathcal{N}(\rho)$ through coherent quantum evolution. Notably, BELT accommodates maps that fall outside the scope of quantum singular value transformation, such as the transpose map. BELT finds applications in entanglement detection, quantum channel inversion, and simulating pseudo-differential operators, and demonstrates improved sample complexity compared to protocols based on Hermitian-preserving map exponentiation.

About the speaker:

Fuchuan Wei is a fifth-year Ph.D. candidate in Yau Mathematical Sciences Center and Department of Mathematical Sciences at Tsinghua University, supervised by Prof. Zhengwei Liu. His research interests include quantum error correction, quantum algorithms, and the effects of quantum noise.