Cascaded silicon-on-insulator double-ring sensors operating in high-sensitivity transverse-magnetic mode

Abstract

We demonstrate ultrahigh-sensitivity silicon photonic sensors based on two cascaded double-ring resonators operating in transverse-magnetic mode. Both wavelength interrogation and intensity interrogation methods are experimentally investigated and the sensitivities reached 24,300 nm/RIU and 2430 dB/RIU, respectively. We also show that the double-ring sensors can be simply cascaded to realize simultaneous detection of multiple species, which is very promising for low-cost array applications.

Theoretical Analysis of a Microring Resonator Array with High Sensitivity and Large Dynamic Range Based on a Multi-Scale Technique

“…Optical microring resonators have extensive applications in wavelength filters [1], label-free biosensors [2,3,4,5], pressure sensors [6,7,8], and acceleration sensors [9,10] due to their outstanding properties of micro-size, the complementary metal-oxide-semiconductor (CMOS) compatibility and immunity to electromagnetic fields [11,12]. In sensor applications, the general sensing theory is that the change in refractive index induced by the external physical variables causes a corresponding shift in the resonant wavelength of the resonator.…”

Label-free biosensing using cascaded double-microring resonators integrated with microfluidic channels

“…These equipments are very expensive and cannot be integrated into one chip. To address these problems, our group has previously proposed and demonstrated a highly sensitive optical sensor based on cascaded double-microring resonators with Vernier effect [14][15][16][17]. The method was then adopted by several other research groups and respectable results have been achieved [18][19][20].…”

“…The method was then adopted by several other research groups and respectable results have been achieved [18][19][20]. We have previously reported a double-microring resonator based sensor exhibiting sensitivity up to 24,300 nm per refractive index unit (RIU) using different concentration solutions of NaCl [17], far surpassing the sensitivity of 135 nm/RIU for a SOI single ring resonator [21] and 12.7 nm/RIU for the polymer dual ring resonators [22]. To detect streptavidin, the cascaded double-microring resonators were further made biotin film immobilized on the surface [23].…”

A Highly Sensitive Refractometric Sensor Based on Cascaded SiN Microring Resonators

“…All of them operate in TE mode. In addition, cascaded SOI MRRs were designed and fabricated for operating in TM mode, where a BRIS of 24,300 nm/RIU was demonstrated [12]. …”