Sensing at terahertz frequency domain using a sapphire whispering gallery mode resonator Mathai, C. ; Jain, Ravikumar ; Achanta, V. G. ; Duttagupta, S. P. ; Ghindani, D. ; Joshi, N. R. ; Pinto, R. ; Prabhu, S. S. Abstract Publication: Optics Letters Pub Date: November 2018 DOI: 10.1364/OL.43.005383 Bibcode: 2018OptL...43.5383M