Chip-Scale Photonic Crystal Spectrometers with High Resolution for Lab-on-a-chip Sensing Applications

Compact on-chip spectrometers with high resolution are an important building block needed in implementing spectral interrogation for optical lab-on-a-chip sensing applications. Photonic crystal (PC) superprism devices provide a proper solution as integrated on-chip spectrometers due to their unique and strong dispersive properties and possibility of implementation in a variety of host materials. Here, we show that by combining three unique PC dispersive properties (superprism effect, negative diffraction, and negative refraction) it is possible to realize a unique spectrometer with high resolution (better that 10 pm) in detecting spectral features. The performance of this device is compared with other spectrometers, and further steps to improve the resolution are discussed.