Spatio-spectral localized modal coupling for room-temperature quantum coherence protection

Wen-Jie Zhou; Yu-Wei Lu; Jing-Feng Liu; Renming Liu; Lay Kee Ang; Ortwin Hess; Lin Wu

doi:10.1515/nanoph-2024-0574

Spatio-spectral localized modal coupling for room-temperature quantum coherence protection

Nanophotonics. 2025 Mar 20;14(7):885-898. doi: 10.1515/nanoph-2024-0574. eCollection 2025 Apr.

Authors

Wen-Jie Zhou^{1

2}, Yu-Wei Lu³, Jing-Feng Liu⁴, Renming Liu⁵, Lay Kee Ang¹, Ortwin Hess⁶, Lin Wu¹

Affiliations

¹ Department of Science, Mathematics and Technology (SMT), Singapore University of Technology and Design (SUTD), 8 Somapah Road, Singapore 487372, Singapore.
² Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, Singapore.
³ Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area (Guangdong), 518045, Shenzhen, China.
⁴ College of Electronic Engineering and College of Artificial Intelligence, South China Agricultural University, 510642, Guangzhou, China.
⁵ School of Physics and Electronics, International Joint Research Laboratory of New Energy Materials and Devices of Henan Province, Henan University, 475004, Kaifeng, China.
⁶ School of Physics and CRANN Institute, Trinity College Dublin, Dublin 2, Ireland.

Abstract

This work aims to advance the room-temperature manipulation of photonic qubits and enhance coherence preservation in and for quantum applications via tailored spatio-spectral localized (SSL) systems. We focus on an innovative all-plasmonic SSL system consisting of a gold bowtie array on a gold substrate. This design produces a high-Q spectral-localized mode through the lattice array, emerging from the collective lattice response of localized surface plasmon resonance (LSPR), particularly the surface lattice resonance (SLR). The SSL system enables tunable modal coupling between the LSPR and SLR, allowing precise alignment with quantum emitters to form quasi-bound states across an energy range of 1.45-1.91 eV. This flexibility allows us to investigate how innovative configurations - such as three-body coupling symmetry and modal-coupling strength - affect coherence protection. These insights pave the way for optimizing SSL systems, setting the stage for significant advancements in nanophotonic qubit manipulation at ambient conditions and the future of photonic quantum systems.

Keywords: coherence; localized surface plasmonic resonance; modal coupling; spatio-spectral localized; spectral hole-burning; surface lattice resonance.