Thermally tunable high-Q metamaterial and sensing application based on liquid metals

Abstract

Achieving a high Q-factor metamaterial unit for a precision sensing application is highly demanded in recent years, and most of the developed high-performance sensors based on the high-Q metamaterial units are due to the dielectric/magnetic property changes of the substrate/superstrate. In this paper, we propose a completely different sensing metamaterial unit configuration, with good sensing sensitivity and precision properties, based on the thermally tunable liquid metals. Specifically, a basic thermally tunable metamaterial unit, the mercury-inspired split ring resonator (SRR), is firstly presented to theoretically show the magnetic resonance and negative permeability frequency band shift properties under different background temperatures. Then, considering the radiation loss mechanism of the conventional SRR metamaterial unit and based on the physically reliable ability of liquid metals, the modified mercury-inspired Fano and toroidal resonators with a large frequency tuning range and high Q-factor are developed and discussed. The numerical demonstrations have shown that the designed Fano and toroidal resonators have much better sensing precision performances compared to the conventional SRR for the temperature sensing application. The experimental demonstrations have also been used to verify the proposed mercury-based toroidal resonators, and good agreements are achieved.

Symmetric resonator based tunable epsilon negative near zero index metamaterial with high effective medium ratio for multiband wireless applications

“…Shift of frequency is 0.5% 4. Tuned resonance frequency is around 3.5 GHz 53 Mercury based toroidal resonator tuned by temperature change 7.2 MHz/°C S-band 1. Resonance frequency shifts to low frequency with increasing temperature 2.…”

“…By controlling the magnetic field of these wires by dc voltage, the resonance frequency can be controlled. On the other hand, in 53 , mercury inspired split ring resonator is described that exhibits magnetic resonance depending on temperature variation. Moreover, a tunable metamaterial filter is presented in 54 that uses two cross coupled split rings.…”

Advanced Electromagnetic Metamaterials for Temperature Sensing Applications

“…Based on the performance enhanced sensing designs by using the asymmetric high quality-factor resonance mode, in the past several years, researchers further proposed other kinds of high quality-factor metamaterial units for sensing applications, including the toroidal resonance [55,[59][60][61], anapole resonance [56,[62][63][64][65][66][67], and enhanced magnetic plasmon resonance [68][69][70][71][72][73][74]. For examples, by placing the period symmetric arrangement of the Fano resonator shown in Figure 2C-i as the mirror symmetric arrangement shown in Figure 2D, one can get the toroidal resonance with quality factor larger than the regular Lorentz resonance [63].…”

Photonic and Plasmonic Metasensors

“…[401,402] Among latest studies, Wen's recent investigation proposed a novel metamaterial configuration with reasonable sensing sensitivity and precision. [403] Thermally tunable liquid metals were employed to create the sensing mechanism. Through a comparative study, a thermally tunable mercury-inspired split-ring resonator metamaterial has been designed and analyzed, where a magnetic resonance and negative permeability frequency band shift feature were observed under different background temperatures.…”