Experimental measurement of the quantum geometric tensor using coupled qubits in diamond. Issue 2 (27th November 2019)

• Record Type: Journal Article
• Authors: Yu, Min; Yang, Pengcheng; Gong, Musang; Cao, Qingyun; Lu, Qiuyu; Liu, Haibin; Zhang, Shaoliang; Plenio, Martin B; Jelezko, Fedor; Ozawa, Tomoki; Goldman, Nathan; Cai, Jianming
• Is Part Of: National science review. Volume 7:Issue 2(2020)
• Page Start: 254
• Page End: 260
• Publication Date: 2019-11-27
• Subjects: quantum geometry -- topological physics -- quantum measurement -- quantum control -- quantum information; Science -- Periodicals; 505
• DOI: 10.1093/nsr/nwz193
• Languages: English
• ISSNs: 2095-5138

Abstract

Abstract: Geometry and topology are fundamental concepts, which underlie a wide range of fascinating physical phenomena such as topological states of matter and topological defects. In quantum mechanics, the geometry of quantum states is fully captured by the quantum geometric tensor. Using a qubit formed by an NV center in diamond, we perform the first experimental measurement of the complete quantum geometric tensor. Our approach builds on a strong connection between coherent Rabi oscillations upon parametric modulations and the quantum geometry of the underlying states. We then apply our method to a system of two interacting qubits, by exploiting the coupling between the NV center spin and a neighboring 13 C nuclear spin. Our results establish coherent dynamical responses as a versatile probe for quantum geometry, and they pave the way for the detection of novel topological phenomena in solid state.