IQIM Postdoctoral and Graduate Student Seminar

Abstract: Nonstabilizerness or 'magic' characterizes the amount of non-Clifford operations needed to prepare quantum states. It is a crucial resource for quantum computing necessary for quantum advantage. However, our understanding of magic had been limited to a few qubits due to a lack of efficient methods to study magic. Recently, we established efficient methods to compute magic on quantum computers [1,2] and matrix product states [3,4]. With our methods, we gain new insights into the magic of quantum computers, its connection with entanglement, and establish fundamental limits on efficiency [5]. Further, we study the magic of critical many-body systems, as well as uncover its universal behavior in dynamical systems [6]. Finally, we discuss how to combine Clifford circuits and matrix product states to efficiently simulate systems with both volume-law entanglement and magic [7].
Our works provide powerful tools to probe the computational complexity of quantum many-body systems.

[1] T. Haug, M.S. Kim, PRX Quantum 4 (2023)
[2] T. Haug, S. Lee, M.S. Kim, Phys. Rev. Lett. 132 (2024)
[3] T. Haug, L. Piroli, Phys. Rev. B 107 (2023)
[4] T. Haug, L. Piroli, Quantum 7 (2023)
[5] N. Bansal, W.K. Mok, K. Bharti, D.E. Koh, T. Haug, arXiv:2407.11607 (2024)
[6] T. Haug, L. Aolita, M.S. Kim, arXiv:2406.04190 (2024)
[7] G. Lami, T. Haug, J. De Nardis, arXiv:2404.18751 (2024) (accepted in PRX Quantum)

Lunch will be provided following the talk.