报告时间：2025年5月12日上午10：00 (10:00, May.12, 2025)

报告地点：物质科研楼C404会议室(Room C404, Material Science Building)

报告人: Prof. Gonzalo A. Alvarez  

报告题目/Title: Quantum sensing tools for out-of-equilibrium systems with magnetic resonance

摘要/Abstract: 

Reliable processing of quantum information is crucial for the development of quantum technologies. Characterizing out-of-equilibrium quantum systems [1–3], which are ubiquitous at quantum scales, is essential for designing optimal control and quantum sensing strategies. However, this task is highly challenging due to the complex high-order correlations and non-stationary nature of such systems. In this talk, I will present a series of methods to characterize the decoherence of out-of-equilibrium quantum systems [1,4–8]. Using quantum simulations with solid-state nuclear magnetic resonance (NMR), we quantify out-of-time-order correlations (OTOCs [2–3]) to define a critical threshold for disturbances that enables reliable control of large quantum systems [1,4–5]. Furthermore, we develop a framework for quantum sensing the dynamics of out-of-equilibrium systems exhibiting non-stationary and non-Markovian features, as well as time-reversal symmetry breaking in quantum dynamics [6-8]. We exploit these insights to introduce a quantum sensing paradigm that quantifies how far the sensed environment is from equilibrium or how intrinsically quantum non-Gaussian it is, a characteristic of strongly coupled environments [7,8]. This approach allows us to discern and filter various environmental properties, including stationary, non-stationary, and non-Gaussian quantum noise fluctuations, advancing toward sensing the ubiquitous environments of quantum sensors at atomic and nanoscales.

[1] G. A. Alvarez, D. Suter, R. Kaiser. Science 349, 846 (2015).

[2] R.J. Lewis-Swan, A. Safavi-Naini, A.M. Kaufman, A.M. Rey. Nat. Rev. Phys. 1, 627 (2019).

[3] B. Swingle. Nat. Phys. 14, 988 (2018).

[4] F.D. Dominguez, M.C. Rodriguez, R. Kaiser, D. Suter, G.A. Alvarez. Phys. Rev. A 104, 012402 (2021).

[5] F.D. Dominguez, G.A. Alvarez. Phys. Rev. A 104, 062406 (2021).

[6] M. Kuffer, A. Zwick, G.A. Alvarez. PRX Quantum 3, 020321 (2022).

[7] M. Kuffer, A. Zwick and G.A. Alvarez. PRX Quantum 6, 020320 (2025)

[8] J.W. Rosenberg, M. Kuffer, I. Zohar, R. Stöhr, A. Denisenko, A. Zwick, G.A. Álvarez, A. Finkler. arXiv:2501.05814

报告人简介/Curriculum Vitae:

Prof. Gonzalo A. Alvarez，任职于阿根廷核能委员会（CNEA）巴里洛切原子能中心与库约国立大学巴尔塞罗研究所。在基础物理与应用技术的交叉领域追求创新研究。已在高影响力国际期刊上发表了60多篇论文（包括5篇综述文章），其中包括对《科学》、《自然-通讯》、《现代物理评论》、《物理评论快报》、《PRX Quantum》、《美国科学院院刊》、《科学报告》、《物理评论应用》等期刊的重要贡献。研究获得了3500多次引用，h指数为30，反映了其影响力和对该领域的相关性。工作主要侧重于开发量子控制方法，该方法利用量子信息和传感的基本原理来推动NMR成像和光谱学应用的发展。