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Open Positions

Soliton combs for quantum light Communications:
Optical combs (which look a lot like hair comb!) are sources with ultra-precise frequencies and ultra-short pulse widths. When the comb lines are locked together, their noise level is vanishingly small and such sources find applications in the most precise clocks for communications in space. Quantum emitters are needed for the generation of light within secure communications. Optical combs can be used to generate single photons as well as generating light that can be used to control and direct the single photons from their origin to the final destination. In this project, we will explore the design of such optical combs and will study the photon dynamics with quantum and classical light coexisting in the system. Finally, using the newly developed Quantum Optical Network (to be located in TCD), we will study the transmission of data on the quantum channels.
photonics

 

Figure on the right shows the comb spectrum with characteristic Sech^2 shape of the soliton. The figure on the right shows the soliton has negligible noise.

Athermal operation of Semiconductor Lasers for energy efficient optical communications.
Semiconductor lasers bring data all around the world through modulation of the light. Since the wavelength of the laser depends on refractive index which also depends on temperature, lasers are generally controlled so that their temperature remains constant. This is achieved by putting the laser on a thermo-electric controller. In operation, the controller expends much more energy than the laser. Our group has developed a method for what is termed athermalisation. In this process, we can keep the laser at a constant temperature even as the ambient temperature is altered. In this project, we will study the designs of lasers to optimise this athermalisation process. We will image the lasers and study how the temperature varies as the power is altered. A key issue is to ensure that the laser power does not change when the ambient temperature changes and we will design and operate semiconductor optical amplifiers for this. We will carry out transmission experiments over optical fiber to see how athermalisation affects their performance.
positions  

 

 

Figure top left- schematic of the laser in our system, top right wavelength map of the laser
Middle- Image of the Temperature Profile of the Laser when operating
Bottom Right and Left. Shows that laser wavelength is essentially unchanged as the temperature is altered- Athermalisation

How to Apply

Funding is provided at €18500 per year and PhD Fees will be paid from the Research Grants.
Contact: jdonegan@tcd.ie