Passively mode-locked quantum dot laser subject to dual long cavity time-delayed optical feedback

• Published in: Materials today : proceedings Vol. 7; pp. 916 - 919
• Main Authors: Nikiforov, Oleg, Drzewietzki, Lukas, Stutz, Sebastian, Breuer, Stefan
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2019
• Subjects: Optical feedback; Passive mode-locking; quantum-dot laser; radio-frequency linewidth; semiconductor laser; timing jitter; timing jitter; radio-frequency linewidth; semiconductor laser; quantum-dot laser; Optical feedback; Passive mode-locking
• ISSN: 2214-7853; 2214-7853
• DOI: 10.1016/j.matpr.2018.12.094

In this contribution, we study experimentally the impact of two long external passive optical cavities on the repetition rate and timing jitter of a monolithic passively mode-locked InAs/InGaAs quantum dot laser. The dual cavity scheme allows to fully suppress feedback induced sidebands in the radio-frequency spectrum. By fine delay control of the optical self-feedback delay lengths, a repetition rate tunability of 9.4 MHz is achieved. The lowest repetition rate line width amounts to less than 50 Hz, corresponding to a timing jitter of 1.7 fs. We explain the experimentally observed timing jitter and repetition rate trends qualitatively by adapting a versatile simple time-domain model. Both experiment and simulations indicate the strongest pulse train timing jitter reduction at feedback lengths that yield the lowest repetition rate frequency deviation