- Lectures
- Institute of Physics
- Location
5F, 1st Meeting Room, Institute of Physics
- Speaker Name
Assistant Prof. Tzu-Kan Hsiao (Department of Physics, National Tsing Hua University)
- State
Definitive
- Url
https://www.phys.sinica.edu.tw/lecture_detail.php?id=2746&eng=T
【Abstract】
Emergent phases of strongly-correlated fermions are of central interest in condensed matter physics. Quantum systems with engineered Hamiltonians can be used as quantum simulators of such many-body systems to provide insights beyond the capabilities of classical computers. Semiconductor gate-defined quantum dot arrays, owing to their in-situ tunable hopping amplitude and chemical potential, naturally-occurring on-site and long-range Coulomb interaction and flexible geometry, are an ideal platform for simulating Fermi-Hubbard physics. In this talk, I will first briefly review the quantum simulation experiments of Mott metal-insulator transition [1] and Nagaoka ferromagnetism [2], which demonstrate the excellent control of interaction parameters in a quantum dot array. I will then introduce our recent work on simulating a Heisenberg antiferromagnetic spin chain [3]. In this experiment, we develop several experimental techniques including many-body spin-state preparation, singlet-triplet correlation measurements, multi-spin energy spectroscopy and global coherent oscillations. We use these techniques to tune and probe a homogeneously coupled spin chain and find good agreement between experiment and numerical simulation. Our demonstrated control and techniques combined with flexibility of the quantum dot lattice geometry design enable new opportunities to simulate quantum many-body systems, including spin liquid physics and quantum phase transitions.
[1] T. Hensgens, T. Fujita, L. Janssen, X. Li, C. J. van Diepen, C. Reichl, W. Wegscheider, S. Das Sarma, and L. M. K. Vandersypen, Quantum Simulation of a Fermi-Hubbard Model Using a Semiconductor Quantum Dot Array, Nature 548, 70 (2017)
[2] J. P. Dehollain, U. Mukhopadhyay, V. P. Michal, Y. Wang, B. Wunsch, C. Reichl, W. Wegscheider, M. S. Rudner, E. Demler, and L. M. K. Vandersypen, Nagaoka Ferromagnetism Observed in a Quantum Dot Plaquette, Nature 579, 528 (2020).
[3] C. J. van Diepen*, T.-K. Hsiao*, U. Mukhopadhyay, C. Reichl, W. Wegscheider, and L. M. K. Vandersypen, Quantum Simulation of Antiferromagnetic Heisenberg Chain with Gate-Defined Quantum Dots, Physical Review X 11, 041025 (2021)