Construction, characterisation and frequency stabilisation of an External Cavity Diode Laser for future high-precision and high-power studies

Details

Supervisors

Lauzin, Clément

Faculty

Faculté des sciences

Degree label

Master [120] en sciences physiques, à finalité approfondie

Abstract

enThis master’s thesis describes the construction, characterisation, and frequency stabilisation of a 1550 nm External Cavity Diode Laser (ECDL). The ECDL was successfully locked to optical cavities of varying finesse using the Pound-Drever-Hall (PDH) locking technique, resulting in a stabilised output frequency and reduction in linewidth. The achieved locks remained stable for a few hours, demonstrating the capability of the PDH technique to maintain frequency stability. The characterisation of the ECDL was performed through linewidth measurements, using the optical heterodyning technique with a frequency comb, and by calculating the overlapping Allan from the time signal of the beat note. These techniques provided insights into the different technical considerations needed to properly characterise an oscillator. Future improvements are proposed to increase the frequency stability over time, with the purpose of developing a home-built optical clock. These improvements include optimising the experimental setup and investigating the temperature and pressure stability of a ULE cavity.