  Quantum Optical Coherence Tomography (Q-OCT) is the non-classical counterpart
of Optical Coherence Tomography (OCT) - a high-resolution 3D imaging technique
based on white-light interferometry. Because Q-OCT uses a source of
frequency-entangled photon pairs, not only is the axial resolution not affected
by dispersion mismatch in the interferometer, but is also inherently improved
by a factor of square root of two. Unfortunately, practical applications of
Q-OCT are hindered by image-scrambling artefacts and slow acquisition times.
Here, we present a theoretical analysis of a novel approach that is free of
these problems: Q-OCT with joint spectrum detection (JS-Q-OCT). Based on a
photon pair coincidence detection as in the standard Q-OCT configuration, it
also discerns, each photon pair by their wavelength. We show that all the
information about the internal structures of the object is encoded in the joint
spectrum and can be easily retrieved through Fourier transformation. No depth
scanning is required, making our technique potentially faster than standard
Q-OCT. Finally, we show that the data available in the joint spectrum enables
artefact removal and discuss prospective algorithms for doing so.
