Events at Physics |
Events on Tuesday, July 16th, 2024
- R. G. Herb Condensed Matter Seminar
- Ultrafast quantum simulation and quantum computing with ultracold atom arrays at quantum speed limit
- Time: 10:00 am - 6:00 pm
- Place: 5310 Chamberlin Hall
- Speaker: Kenji Ohmori, Institute for Molecular Science (IMS), National Institutes of Natural Sciences, Japan
- Abstract: Many-body correlations drive a variety of important quantum phenomena and quantum machines including superconductivity and magnetism in condensed matter as well as quantum computers. Understanding and controlling quantum many-body correlations is thus one of the central goals of modern science and technology. My research group has recently pioneered a novel pathway towards this goal with nearby ultracold atoms excited with an ultrashort laser pulse to a Rydberg state far beyond the Rydberg blockade regime [1-7]. We first applied our ultrafast coherent control with attosecond precision [2,3] to a random ensemble of those Rydberg atoms in an optical dipole trap, and successfully observed and controlled their strongly correlated electron dynamics on a sub-nanosecond timescale [1]. This new approach is now applied to arbitrary atom arrays assembled with optical lattices or optical tweezers that develop into a pathbreaking platform for quantum simulation and quantum computing on an ultrafast timescale [4-7]. In this ultrafast quantum computing, as schematically shown in Fig. 1, we have recently succeeded in executing a controlled-Z gate, a conditional two-qubit gate essential for quantum computing, in only 6.5 nanoseconds at quantum speed limit, where the gate speed is solely determined by the interaction strength between two qubits [5]. This is, faster than any other two-qubit gates with cold-atom hardware by two orders of magnitude. It is also two orders of magnitude faster than the noise from the external environment and operating lasers, whose timescale is in general 1 microsecond or slower, and thus can be safely isolated from the noise. Moreover, this two-qubit gate is faster than the fast two-qubit gate demonstrated recently by “Google AI Quantum” with superconducting qubits [8]. References [1] N. Takei et al., Nature Commun. 7, 13449 (2016). Highlighted by Science 354, 1388 (2016); IOP PhyscisWorld.com (2016). [2] H. Katsuki et al., Acc. Chem. Res. 51, 1174 (2018). [3] C. Liu et al., Phys. Rev. Lett. 121, 173201 (2018). [4] M. Mizoguchi et al., Phys. Rev. Lett. 124, 253201 (2020). [5] Y. Chew et al., Nature Photonics 16, 724 (2022). (Front Cover Highlight) [6] V. Bharti et al., Phys. Rev. Lett. 131, 123201 (2023). [7] V. Bharti et al., arXiv:2311.15575 (2023). [8] B. Foxen et al., Phys. Rev. Lett. 125, 120504 (2020).
- Host: Robert McDermott
- Wisconsin Quantum Institute
- Quantum Coffee Hour
- Time: 3:00 pm - 4:00 pm
- Place: Rm.5294, Chamberlin Hall
- Abstract: Please join us for the WQI Quantum Coffee today at 3PM in the Physics Faculty Lounge (Rm.5294 in Chamberlin Hall). This series, which takes place approximately every other Tuesday, aims to foster a casual and collaborative atmosphere where faculty, post-docs, students, and anyone with an interest in quantum information sciences can come together. There will be coffee and treats.