Experimental Quantum Optics Group at ICN-UNAM


In our research group we have designed and implemented a variety of non-classical light sources with tailored spatio-temporal properties, in accordance with particular needs. For this purpose, we have explored the use of wide variety of optical devices and techniques including ultrashort (ps and fs) pulses, dispersion engineering, nonlinear waveguides, single- and few-mode specialty fibers (e.g. microstructured and tapered fibers), structured beams, as well as photonic lanterns. Most of our work has been based on spontaneous parametric processes in second- and third-order materials. This includes photon pair generation through the processes of spontaneous parametric downconversion in nonlinear crystals and spontaneous four wave mixing in fibers, as well as photon triplet generation through third-order spontaneous parametric downconversion in fibers. In addition, we have exploited such sources for a variety of applications and situations including random number generation, entangled-photon absorption spectroscopy, quantum optical coherence tomography, as well as testing Einstein Podolsky Rosen elements of reality.

Some of our recent work includes: progress towards practical quantum optical coherence tomography, progress towards photon triplet generation, testing Einstein Podolsky Rosen elements of reality, entangled-photon absorption spectroscopy, and the exploitation and characterization of the spatial degree of freedom of photon pairs.

Quantum optical coherence tomography:

Photon triplet generation:

Testing Einstein Podolsky Rosen elements of reality:

  • O. Calderón-Losada, T. Moctezuma, H. Cruz-Ramirez, S. Murgueitio Ramírez, A. B. U'Ren, A. Botero, and A. Valencia, "A weak values approach for testing simultaneous Einstein-Podolsky-Rosen elements of reality for non-commuting observables" accepted Communications Physics (2020)

Spatial degree of freedom of photon pairs:

Entangled-photon absorption spectroscopy:


Dr. Alfred U'Ren

Tenured Research Scientist
Investigador Titular C (PRIDE D)
equivalent to
Full Professor

Member of National System of Researchers, level III (highest)

Member of the Mexican Academy of Sciences

Recipient of Mexican Academy of Sciences Research Prize (Exact Sciences), 2013


+52(55) 5622-4681

Secretary (Lucila Gonzalez Loperena):
+52(55) 5622-4672