Submicron axial resolution in an ultrabroadband two-photon interferometer using superconducting single-photon detectors.
We generate ultrabroadband biphotons via the process of spontaneous parametric down-conversion in a quasi-phase-matched nonlinear grating that has a linearly chirped poling period. Using these biphotons in conjunction with superconducting single-photon detectors (SSPDs), we measure the narrowest Hong-Ou-Mandel dip to date in a two-photon interferometer, having a full width at half maximum (FWHM) of approximately 5.7 fsec. This FWHM corresponds to a quantum optical coherence tomography (QOCT) axial resolution of 0.85 ?m. Our results indicate that a high flux of nonoverlapping biphotons may be generated, as required in many applications of nonclassical light.
Nasr
Magued B
MB
Departments of Electrical & Computer Engineering and Physics, Quantum Imaging Laboratory, Boston University, Boston, MA 02215, USA. boshra@bu.edu
Minaeva
Olga
O
Goltsman
Gregory N
GN
Sergienko
Alexander V
AV
Saleh
Bahaa E
BE
Teich
Malvin C
MC
D003198:Computer Simulation; D017076:Computer-Aided Design; D004553:Electric Conductivity; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007368:Interferometry / Q000295:instrumentation*; D008962:Models, Theoretical; D017785:Photons