Generation of tunable fields for optical amplifiers

• Grant number: 21/02615-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2021
• End date: April 30, 2022
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Marcelo Martinelli
• Grantee: Gabriel Moniz Arantes
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 15/18834-0 - Exploring quantum information with atoms, crystals and chips, AP.TEM

Abstract

The final goal of the associated project is the generation of entangled states for applications in quantum information processing in a scalable structure of field modes. For this implementation, the development of optical amplifiers for applications in quantum information relies on the careful engineering of the parametric coupling. This can be done by tailoring the gain medium or the manipulation of the pumping field of the parametric amplifier.The project aims the generation of two coherent fields, with well-defined phase relations but a frequency diference in the MHz range. That should be done by using a Ti:sapphire laser as a gain medium for the field generated by a diode laser. Frequencies will be controlled by an acousto-optic modulator. The whole system will work on a master oscillator power amplifier architecture (MOPA).While the diode laser is well known as a versatile source of coherent light, with a great excess noise in the phase, we have developed a new setup that reduces this excess noise to 10 dB above the coherent state reference. This excess noise could be easily filtered by a cavity. The output will be modulated and injected in a Ti:sapphire laser, that had its control elements removed. The amplifier laser will follow the model field delivered by the master oscillator with minimal intracavity losses, delivering the necessary power of our four wave mixing setup, in the heart of the parametric amplifier.