Excitation of Bloch Surface Waves in Zero-Admittance Multilayers for High-Sensitivity Sensor Applications

Abstract

The growing need for classical as well as quantum optical sensing places increasingly stringent requirements upon the desired characteristics of the engendered fields. Specifically, achieving superior field enhancement plays a critical role in applications ranging from chem-bio sensing, Raman and infrared spectroscopies to ion trapping and qubit control in emerging quantum-information science. Due to their low optical losses and ability to exhibit resonant field enhancements, all dielectric multilayers are emerging as an optical material system not only useful to classical photonics and sensing but also of potential to be integrated with quantum materials and quantum sensing. The recently introduced concept of zeroadmittance layers [1] within dielectric multilayer materials, enables the creation and control of resonant fields orders of magnitude larger than the exciting field. Here, invoking the zero-admittance concept, we design, fabricate, and characterize an all-dielectric nonabsorbing stack and demonstrate the engendered huge field enhancement. Describing the fields in terms of Bloch surface waves, we connect the surface field to the semiperiodicity in the dielectric domains of the stack. As a specific application of the resonant field, we propose and demonstrate refractive-index sensing for the detection of trace amounts of an analyte. The results include a quantification of the sensitivity of the device with respect to the profile of the exciting field. The experimental results are shown to be in good agreement with theoretical calculations.

Excitation of Hybrid Waveguide-Bloch Surface States with Bi2Se3 Plasmonic Material in the Near-Infrared Range

“…in nature, as their momentum is larger than the free-space wave momentum [30,31]. Thus, we use a prism to provide additional momentum to the incident wave to excite BSWs.…”

“…The BSW modes are excited because of the surface defect. Although such modes are intrinsically present at Bi 2 Se 3 –air interfaces, they are non-radiative in nature, as their momentum is larger than the free-space wave momentum [ 30 , 31 ]. Thus, we use a prism to provide additional momentum to the incident wave to excite BSWs.…”

Centimeter‐Scale Propagation of Optical Surface Waves at Visible Wavelengths

“…Over the past 40 years, many studies have explored the possibilities offered by Bloch surface waves (BSWs), from the near-UV to mid-infrared wavelengths, [22][23][24][25][26][27][28][29][30] particularly for sensing applications. [31][32][33][34][35][36] Still, only very few works have discussed their propagation properties [37,38] and even fewer have made reports of experimentally measured propagation lengths. [39,40] At visible wavelengths, the longest propagation lengths achieved range in the order of a few hundred micrometers.…”

Surface‐Enhanced Mid‐IR Gas Sensor Employing Wavelength‐Tunable Bloch Surface Waves

“…Despite these exciting potentials, the reported BSWs platforms mainly focus on sensing chemical compounds solely based on their refractive index in the visible and near-IR regions. [22][23][24] For refractive index sensing, it cannot discriminate two compounds with the same refractive index, nor could it be accurate when the sensor is working near the absorption lines of compounds. Recently, BSWs platform operating in mid-IR fingerprint region had been successfully demonstrated and characterized, showing great potential for the ultrasensitive detection and label-free sensing of trace molecules based on surface-enhanced spectroscopy.…”