Single-shot on-chip spectral sensors based on photonic crystal slabs

Abstract

Miniaturized spectrometers have significant potential for portable applications such as consumer electronics, health care, and manufacturing. These applications demand low cost and high spectral resolution, and are best enabled by single-shot free-space-coupled spectrometers that also have sufficient spatial resolution. Here, we demonstrate an on-chip spectrometer that can satisfy all of these requirements. Our device uses arrays of photodetectors, each of which has a unique responsivity with rich spectral features. These responsivities are created by complex optical interference in photonic-crystal slabs positioned immediately on top of the photodetector pixels. The spectrometer is completely complementary metal–oxide–semiconductor (CMOS) compatible and can be mass produced at low cost.

On‐Chip Measurement of Photoluminescence with High Sensitivity Monolithic Spectrometer

“…[ 1–4 ] Currently, rapid development of footprint shrinking is available for microspectrometer chips through the instrumentality of sophisticated light splitting techniques [ 5–9 ] such as quantum dot filters [ 10 ] or photonic structures. [ 11–14 ] In such devices, the primary shortcoming lies in key sensor performance metrics, including sensitivity and resolution, scale inversely with the effective optical path length, and light–matter interaction volume. [ 3,15–17 ] As a consequence, simple size down‐scaling of conventional spectroscopic sensor designs makes it against the urgent need of on‐chip probing and characterizing a small amount of light emission, such as measuring photoluminescence (PL), Raman analysis, and single particle scattering.…”

Compressive Sensing Spectroscopy Using a Residual Convolutional Neural Network

“…Note that several sparsifying bases have been used in CS spectroscopy such as a family of orthogonal Daubechies wavelets [7], a Gaussian line shape matrix [8,9], and a learned dictionary [10]. Furthermore, numerous optical structures have been proposed to attain the necessary small mutual coherence for sensing patterns such as thin-film filters [11,12], a liquid crystal phase retarder [13], Fabry-Perot filters [7,14], and photonic crystal slabs [15,16]. As algorithms for reconstructing the original signal, two types of basic reconstruction techniques have been developed: greedy iterative algorithms [17,18] and convex relaxation [19,20].…”

“…In CS spectroscopy, the reconstruction algorithms have been used with a sparsity constraint. Additionally, a non-negativity constraint is used in Reference [16,21]. Combining these three considerations, CS spectrometers have shown stable performance for light-emitting diodes (LEDs) and monochromatic lights.…”

MetaNet: a new paradigm for data sharing in photonics research

“…Photonics engineering, in which materials are geometrically structured to tailor their near-and far-field electromagnetic responses, has greatly shaped many technological domains, including communications [1][2][3][4], image sensors [5][6][7][8][9], energy harvesting [10][11][12][13], and medical diagnostics [14,15]. Traditionally, photonics engineering has been driven by design concepts based on relatively simple geometries.…”