Electronic THz-spectrometer for plasmonic enhanced deep subwavelength layer detection

We demonstrate the operation of a miniaturized all-electronic CMOS based THz spectrometer with performances comparable to that of a THz-TDS spectrometer in the frequency range 20 to 220 GHz. The use of this all-electronic THz spectrometer for detection of a thin TiO₂ layer and a B. subtilis bacteria film on top of a plasmonic surface is evaluated. The detection of deeply subwavelength layers with comparable performance as a femtosecond laser based THz-TDS spectrometer is demonstrated. The size of the all-electronic spectrometer is 5 cm by 1cm. The high degree of integration of this spectrometer in combination with plasmonics enhanced sensitivity opens the way to bring THz spectroscopy to consumer applications or to the practitioner´s office.