Abstract-Broadband Electromagnetic Waves Harvesting Based on Effective Surface Plasmon Polaritons

Kuan Wang, Zhuo Li, Liangliang Liu, Yu Luo,

https://www.researchgate.net/publication/325830597_Broadband_Electromagnetic_Waves_Harvesting_Based_on_Effective_Surface_Plasmon_Polaritons

In this paper, a novel structure is proposed for broadband electromagnetic energy harvesting based on effective surface plasmon polaritons (ESPPs) under the framework of conformal transformation optics(TO). By inserting a dielectric cylindrical structure with crescent-shaped cross-section into a dielectric-filled rectangular waveguide, the transverse-electric (TE) mode in the waveguide is smoothly transformed into ESPPs at the bottom of the crescent and propagate towards the singularity of the crescent with decreasing velocity down to zero. The ESPPs energy is harvested all the way towards the singularity due to the interaction between compressed ESPPs and the surrounding lossy dielectrics and metallic wires. Simulation results show that broadband transformation and energy harvesting of ESPPs with efficiency about 25% can be achieved in this scheme. This work paves the way for broadband EM energy harvesting at microwave and terahertz frequencies.

Abstract-Tuning the dispersion of effective surface plasmon polaritons with multilayer systems

Zhuo Li, Yunhe Sun, Kuan Wang, Jiajia Song, Jianfeng Shi, Changqing Gu, Liangliang Liu, and Yu Luo

https://www.osapublishing.org/oe/abstract.cfm?uri=oe-26-4-4686&origin=search

Recently, effective surface plasmon polaritons (ESPPs) induced by structural dispersion in bounded waveguides were theoretically demonstrated and experimentally verified. Despite the theoretical and experimental efforts, whether ESPPs can mimic real SPPs in every aspect still remains an open question. In this work, we go one step further to study the hybridization of ESPPs in multilayer systems. We consider transverse electric (TE) modes in a conventional rectangular waveguide and a parallel-plate waveguide (PPW) and derive analytically the dispersion relations and asymptotic frequencies of the corresponding ESPPs modes in sandwiched structures consisting of alternating dielectrics of different permittivities. Our results show that the ESPPs can be categorized into odd and even parities (owing to the ‘plasmon’ hybridization) in a similar way as natural SPPs supported by the insulator/metal/insulator (IMI) and metal/insulator/metal (MIM) heterostructures in the optical regime. The similarities and differences between ESSPs and their optical counterparts are also discussed in details, which may provide valuable guidance for future application of ESPPs at the microwave and terahertz frequencies.

© 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Abstract-On-chip sub-terahertz surface plasmon polariton transmission lines with mode converter in CMOS

Anak Agung,  Alit Apriyana,, Hao Yu, Jincai Wen, Nan Li, Yu Luo,  Lingling Sun, Yuan Liang, 

http://www.nature.com/articles/srep30063

An on-chip low-loss and high conversion efficiency plasmonic waveguide converter is demonstrated at sub-THz in CMOS. By introducing a subwavelength periodic corrugated structure onto the transmission line (T-line) implemented by a top-layer metal, surface plasmon polaritons (SPP) are established to propagate signals with strongly localized surface-wave. To match both impedance and momentum of other on-chip components with TEM-wave propagation, a mode converter structure featured by a smooth bridge between the Ground coplanar waveguide (GCPW) with 50 Ω impedance and SPP T-line is proposed. To further reduce area, the converter is ultimately simplified to a gradual increment of groove with smooth gradient. The proposed SPP T-lines with the converter is designed and fabricated in the standard 65 nm CMOS process. Both near-field simulation and measurement results show excellent conversion efficiency from quasi-TEM to SPP modes in a broadband frequency range. The converter achieves wideband impedance matching (<−9 dB) with excellent transmission efficiency (averagely −1.9 dB) from 110 GHz–325 GHz. The demonstrated compact and wideband SPP T-lines with mode converter have shown great potentials to replace existing waveguides as future on-chip THz interconnects. To the best of the author’s knowledge, this is the first time to demonstrate the (sub)-THz surface mode conversion on-chip in CMOS technology.

Abstract-A combined system for efficient excitation and capture of LSP resonances and flexible control of SPP transmissions

Zhen Liao, Xiaopeng Shen, Bai Cao Pan, Jie Zhao, Yu Luo and Tie Jun Cui

ACS Photonics

DOI: 10.1021/acsphotonics.5b00096

http://pubs.acs.org/doi/abs/10.1021/acsphotonics.5b00096?journalCode=apchd5

We propose a compact combined system which supports compound spoof surface resonances due to the coupling between spoof surface plasmon polaritons (SPPs) and localized surface plasmons (LSPs). The system is composed of ultrathin metallic spiral structures for discrete LSP resonances and an ultrathin corrugated metallic strip to guide continuous SPP modes. We demonstrate both theoretically and experimentally that the LSP resonances can be efficiently excited and captured by the SPP waveguide, while the SPP transmissions can be judiciously controlled by the LSP structures. The spoof SPP-LSP combined system may find potential applications in sensing and integrated photonic circuitry in the microwave and terahertz frequencies.

Abstract-High-order localized spoof surface plasmon resonances and experimental verifications

• Zhen Liao,
• Yu Luo,
• Antonio I. Fernández-Domínguez,
• Xiaopeng Shen,
• Stefan A. Maier
• & Tie Jun Cui

http://www.nature.com/srep/2015/150410/srep09590/full/srep09590.html

We theoretically demonstrated and experimentally verified high-order radial spoof localized surface plasmon resonances supported by textured metal particles. Through an effective medium theory and exact numerical simulations, we show the emergence of these geometrically-originated electromagnetic modes at microwave frequencies. The occurrence of high-order radial spoof plasmon resonances is experimentally verified in ultrathin disks. Their spectral and near-field properties are characterized experimentally, showing an excellent agreement with theoretical predictions. Our findings shed light into the nature of spoof localized surface plasmons, and open the way to the design of broadband plasmonic devices able to operate at very different frequency regimes.