High-volume-resolution quantum optical coherence tomography imaging with efficient artifact removal.

Optical coherence tomography (OCT) has been widely used in many applications owing to its non-invasive nature. However, its axial resolution can be degraded due to dispersion in samples and optical systems. Quantum optical coherence tomography (QOCT) can overcome this problem and has thus attracted attention. However, QOCT exhibits two challenges: insufficient volume resolution and artifacts in images. Here, we realize high-volume-resolution QOCT imaging with efficient artifact removal. We evaluate our QOCT system to have an axial resolution of 1.5 μm and a lateral resolution of 1.6 μm, giving a volume resolution of 4.0 μm3 (4.0 fL). We show that high-volume-resolution QOCT imaging is achievable even under group velocity dispersion. We also show that artifacts appearing inherently in the QOCT images can be removed by fast post-processing using the maximum clique search in graph theory. We believe that this study paves the way for QOCT imaging of three-dimensional fine structures.