Temperature Stabilization of a non-linear crystal inside a optical doubling cavity

• Grant number: 24/13833-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2024
• End date: June 30, 2025
• Field of knowledge: Physical Sciences and Mathematics - Physics - Atomic and Molecular Physics
• Principal Investigator: Emanuel Alves de Lima Henn
• Grantee: Caio César Rocha Lima
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

Nonlinear optical systems for frequency doubling make use of special crystals with nonlinear properties. In the specific case of crystals of the ``periodic-pooled'' (PP) type, the frequency doubling process is optimized by obtaining quasi phase matching between the original light that is to be double and the light generated by the doubling process. This phase matching is achieved by periodically reversing domains of the non-linear medium and the period of these domains is optimized for the wavelength with which one wishes to work. For this reason, it is not uncommon for such crystals to have to operate at temperatures different from the environment for the purpose of optimizing the nonlinear process. In our case, we use a PPKTP crystal used to generate light at 421nm from 842nm for trapping and cooling Dysprosium atoms and which has an optimized operating temperature of around 46oC. At the moment, this temperature is obtained by heating with resistors and a stabilization circuit, but this is not sufficiently stable and needs to be improved. In this project we will plan, design, print in resin and evaluate the performance of a furnace for stabilizing the temperature of the non-linear PPKTP crystal.