A new double-line waveguide architecture for photonic applications using fs laser writing in Nd3+ doped GeO2-PbO glasses

Author(s)

Bordon, Camila D. S. ; Dipold, Jessica ; Freitas, Anderson Z. ; Wetter, Niklaus U. ; de Rossi, Wagner ; Kassab, Luciana R. P.

• Document type: Journal article
• Source: Optical Materials; v. 129, p. 6-pg., 2022-07-01.

Abstract

A new double-line waveguide architecture produced in Nd3+ doped GeO2-PbO glasses is presented for photonic applications. The waveguides are written directly into Nd3+ doped GeO2-PbO glasses using a Ti:Sapphire femtosecond (fs) laser, operating at 800 nm, delivering 30 fs pulses at 10 kHz repetition rate and writing speed of 0.5 mm/s. Two parallel lines form a dual-waveguide each line being a result of either 4 or 8 superimposed lines. Results of propagation losses, M2 beam quality factor at 632 and 1064 nm, refractive index change, and relative gain at the signal wavelength (1064 nm) are presented. Structural changes, due to laser writing process were investigated by Raman spectroscopy. The observed near-field pattern image showed good waveguiding quality, consisting of a single, circular lobe. X,y-symmetrical guiding for both waveguides was observed. The relative gain reached 4.5 and 6.0 dB/cm for 4 and 8 superimposed lines, respectively, for 420 mW of 808 nm pumping. Propagation losses were 0.89 and 0.44 dB/cm, for 4 and 8 superimposed lines, respectively, leading to positive internal gain of 3.6 and 5.56 dB/cm. The results obtained in the present work demonstrate that this new double line architecture for Nd3+ doped GeO2-PbO glasses is promising for the fabrication of integrated amplifiers, lossless components and lasers. (AU)

• FAPESP's process: 13/26113-6 - Micromachining with ultrashort laser pulses applied to the production and control of optofluidic circuits
• Grantee: Wagner de Rossi
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 17/50332-0 - Scientific, technological and infrastructure qualification in radiopharmaceuticals, radiation and entrepreneurship for health purposes (PDIp)
• Grantee: Marcelo Linardi
• Support Opportunities: Research Grants - State Research Institutes Modernization Program
• FAPESP's process: 18/19240-5 - Multi-user equipment approved in grant 2017-50332-0: STM-AFM Raman SNOM analysis system
• Grantee: Anderson Zanardi de Freitas
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 16/02326-9 - Micromachining with ultrashort laser pulses applied to the production and control of optofluidics circuits
• Grantee: Diego Silvério da Silva
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/10765-5 - Highly efficient low threshold lasers in transparent and scattering media.
• Grantee: Niklaus Ursus Wetter
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/06334-4 - Advanced photonic devices for microfluidic systems: random lasers
• Grantee: Jessica Dipold
• Support Opportunities: Scholarships in Brazil - Post-Doctoral