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Nonlinear Optics for Quantum Communications
- Coordinator : Paul Voss
- Post-doc : David Chapron
Objective : New coherent optical photon sources for applications in optical quantum communications.
Light sources used in quantum cryptography and quantum calculations are currently limited by the use of single photon (linear optic) or by the use of double photons created in non-linear crystal by a second order process. A photon source using the inverse process of third harmonic generation, a third order parametric amplifier, will permit the production of triply correlated photons. Because of the weakness of 
(3) this should be performed in a waveguide.
To accomplish this objective, new optical devices are required :
- phase matching of pure third order (3) process
- large bandwidth
- some manufacturing tolerances.
The non-linear optics research team is designing and constructing such devices.
Pure third harmonic generation efficiency is currently around 2% for low rate regenerating amplified pulses in bulk crystal. To obtain this result, high optical power and low repetition rate are needed to generate a third harmonic wave in the non-linear crystal, but without phase-matching. In contrast, our approach is based on the use of waveguides to obtain an effective third harmonic generation process at a high rate to confine the electrical field (Fig.1).
. (b) Calculation results which show the mode profile at 3 in the waveguide.
The experimental setup for third harmonic generation is composed of a Coherent femtosecond Ti-Saphir laser (Verdi V10 (10W, 76MHz) + Mira 900F) followed by an OPO (Fig. 2).
This setup can generate femtosecond pulses with a large bandwidth of the output signal wavelength from near-IR to near-UV (Fig. 3).
Keywords
optics
-->Nonlinear Optics for Quantum Communications
- Coordinator : Paul Voss
- Post-doc : David Chapron
Objective : New coherent optical photon sources for applications in optical quantum communications.
Light sources used in quantum cryptography and quantum calculations are currently limited by the use of single photon (linear optic) or by the use of double photons created in non-linear crystal by a second order process. A photon source using the inverse process of third harmonic generation, a third order parametric amplifier, will permit the production of triply correlated photons. Because of the weakness of (3) this should be performed in a waveguide.
To accomplish this objective, new optical devices are required :
- phase matching of pure third order (3) process
- large bandwidth
- some manufacturing tolerances.
The non-linear optics research team is designing and constructing such devices.
Pure third harmonic generation efficiency is currently around 2% for low rate regenerating amplified pulses in bulk crystal. To obtain this result, high optical power and low repetition rate are needed to generate a third harmonic wave in the non-linear crystal, but without phase-matching. In contrast, our approach is based on the use of waveguides to obtain an effective third harmonic generation process at a high rate to confine the electrical field (Fig.1).
. (b) Calculation results which show the mode profile at 3 in the waveguide.
The experimental setup for third harmonic generation is composed of a Coherent femtosecond Ti-Saphir laser (Verdi V10 (10W, 76MHz) + Mira 900F) followed by an OPO (Fig. 2).
This setup can generate femtosecond pulses with a large bandwidth of the output signal wavelength from near-IR to near-UV (Fig. 3).
Keywords
optics
