Entanglement among the transverse modes of an Optical Parametric Oscillator

• Grant number: 24/02882-5
• Support Opportunities: Scholarships in Brazil - Master
• Start date: September 01, 2024
• End date: February 28, 2026
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Marcelo Martinelli
• Grantee: Lorenzo Kesikowski Follador
• Host Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 22/09436-5 - Information in quantum optics, AP.TEM

Abstract

The recent developments on optical parametric oscillators (OPOs) using alkali atoms have shown their ability to generate entanglement using a robust setup, with the possibility to reach new records in squeezing levels in a competitive way, when compared to their solid state counterparts. Moreover, given the high gain provided by the amplifying medium, they present more versatile configurations for the optical cavities.Among the possibilities, we can work with extremely lossy cavities, leading to soft transitions on the oscillation threshold, in one hand, and the spontaneous oscillation in higher order transverse modes. The latest characteristic is directly associated to the studied in structured light, and make these systems and excellent instrument for the investigation of spatial multimode entanglement. This feature enables interesting possibilities to extend the existing channels for implementation of quantum communication protocols.The graduate student will have the opportunity to investigate the production of transverse modes in these OPOs, based on four wave mixing in rubidium-85 atoms, and the entanglement among the multiple modes that are produced in the cavity in the two distinct wavelengths (signal and idler) when working above the oscillation threshold.