Dr. Kyuman Cho (Sogang University)
Novel balanced-path homodyne and heterodyne I/Q-interferometer schemes and theirapplications: from biosensors to a local sensor for KAGRA
We have been using an I/Q-interferometer, either a homodyne or heterodyne, in many high sensitivity sensor applications because it can measure the phase and amplitude change induced on the probe beam simultaneously. In most of these sensor applications, interferences caused by environmental perturbations are major noise sources for limiting the sensitivity and reliability. We recently developed the balanced-path arrangement which can minimize interferences caused by environmental perturbations. In this seminar, various sensor applications related to this new interferometer scheme including a scanning coherent microscope, readout sen sor for micro-fluidic channel and protein biochip will be presented. We will also discuss about a high resolution, high stability tilt sensor which is proposed to be used for initial mirror alignment in KAGRA.