Studying light-matter interaction with broadband entangled photons (Prof. A. Stefanov)
- Datum: 19.11.2015
- Uhrzeit: 10:30 - 12:00
- Vortragende(r): Prof. André Stefanov, Universität Bern, Laser Physics Division, Quantum Optics Lab
- Raum: B 0.21
- Gastgeber: MPQ, Attosecond Physics Division, Dr. Hirofumi Yanagisawa
Theoretical proposals have suggested that energy-entangled photons offer
new control parameters for two-photon spectroscopy. Varying
entanglement parameters permits to access to virtual states whose energy
exceed that of the initial-to-final state transition [B. Saleh, et al.,
PRL, 80(16), 3483 (1998)], while it is expected that excitation of
chromophore aggregates with non-classical light reveals the level
structure of the double-exciton manifold [F. Schlawin, et al., PRA,
86(2), 1-10 (2012)]. Broadband energy entangled photons from parametric
downconversion are a promising source of quantum light to study such
effects. Their wave function can be shaped by techniques similar to the
shaping of short laser pulses opening the door to spectroscopy studies.
We demonstrate the application of various transfer functions to the
entangled photons by simultaneously shaping both phase and amplitude
with a pulse shaper based on a spatial light modulator. We show how the
two-photon wave function can be characterized by applying
interferometric autocorrelation schemes. Additionally we study effects
of a dispersive medium on the two photon wave function.Finally broadband
energy-entangled photons possess a very large entanglement content, as
shown by computing the entropy of entanglement. This entanglement can be
used for quantum information processing in high dimensional spaces. We
show results of quantum tomography and various Bell inequalities
measurements.