报告题目：Quantum Optics with Spins and Superconducting Cavities

报 告 人：Johannes Majer，教授，中国科学技术大学上海分部量子信息与量子物理中心。

报告地点：格物楼D座-118报告厅

报告时间：2024年12 月05日 15:00-16:00

报告摘要：Hybrid quantum systems based on spin-ensembles coupled to superconducting microwave cavities are promising candidates for robust experiments in cavity quantum electrodynamics (QED) and for future technologies employing quantum mechanical effects. In particular the electron spins hosted by nitrogen-vacancy centers in diamond. We used this system to study a broad variety of effects, such as cavity protection effect and hole burning which can extend the coherence time and reduce dephasing. Furthermore, this platform allows to study super radiance and the coupling of spins over macroscopic distances. We use a dispersive detection scheme based on cQED to observe the spin relaxation of the negatively charged nitrogen vacancy center in diamond. We observe exceptionally long longitudinal relaxation times T1 of up to 8h. To understand the fundamental mechanism of spin-phonon coupling in this system we develop a theoretical model and calculate the relaxation time ab-initio. The calculations confirm that the low photonic density of states at the NV^- transition frequency enables the spin polarization to survive over macroscopic timescales.

报告人简介：Johannes Majer，中国科学技术大学上海分部，量子信息与量子物理中心全职教授。2003年至2007年在耶鲁大学Robert Schoelkopf 团队担任博士后研究员，主要研究电路量子电动力学和传输子量子比特。2007-2019年，在维也纳理工大学担任助理教授，在此期间开创将超导谐振器与系综金刚石氮空位色心自旋相结合的混合量子系统实验研究。2020年，入职中国科学技术大学。以第一作者或者通讯作者身份发表：Nature 5篇，Nat. Phys. 2篇，Nat. Mater. 1篇，Nat. Photon. 1篇，以及Phys. Rev. Lett. 7篇。

供稿审核：刘广强

编辑审核：王文志

终审：满忠晓