Diode-pumped Alexandrite laser with passive SESAM Q-switching and wavelength tunability

Abstract

We report the first experimental demonstration of a wavelength tunable passively Q-switched red-diode-end pumped Alexandrite laser using a semiconductor saturable absorber mirror (SESAM). We present the results of the study of passive SESAM Q-switching and wavelength-tuning in continuous diode-pumped Alexandrite lasers in both linear cavity and X-cavity configurations. In the linear cavity configuration, pulsed operation up to 27 kHz repetition rate in fundamental TEM00 mode was achieved and maximum average power was 41 mW. The shortest pulse generated was 550 ns (FWHM) and the Q-switched wavelength tuning band spanned was between 740 nm and 755 nm. In the X-cavity configuration, a higher average power up to 73 mW, and obtained with higher pulse energy 6.5 J at 11.2 kHz repetition rate, in fundamental TEM00 mode with excellent spatial quality M2 < 1.1. The Q-switched wavelength tuning band spanned was between 775 nm and 781 nm

Graphene mode-locked femtosecond Alexandrite laser

“…Recently, there has also been a renewed interest in the development of Alexandrite Cr 3 :BeAl 2 O 4 lasers, following the emergence of efficient diode or solid-state pump lasers in the visible. To date, efficient pulsed and continuous-wave regimes of operation have been demonstrated [12][13][14][15][16][17]. Furthermore, by utilizing the broad tuning range of the Alexandrite gain medium, several recent studies have focused on ultrashort pulse generation.…”

Q-Switched Erbium-Doped Fiber Laser Utilizing Tungsten Disulfide Deposited Onto D-Shaped Fiber as Saturable Absorber

“…Q-switching is one of the main techniques to produce a train of energetic short pulses [1][2][3]. It can be passively achieved by deployment of saturable absorber (SA) device inside the laser cavity [4][5][6][7][8][9]. On the other hand, research on fiber lasers have been extensively carried out in recent years due to their many advantages such as simple structure, low cost, small size, and high environmental stability.…”

“…On the other hand, research on fiber lasers have been extensively carried out in recent years due to their many advantages such as simple structure, low cost, small size, and high environmental stability. Passively Q-switched fiber lasers were previously demonstrated using semiconductor saturable absorber mirrors (SESAMs) [4]. However, SESAMs have many drawbacks, such as narrow working bandwidth and complex manufacturing packages and this has greatly limited their application in the development of pulsed fiber lasers.…”

Temperature dependence of Alexandrite effective emission cross section and small signal gain over the 25-450 °C range

“…In the early years of its development, these favorable properties made Alexandrite the laser of choice in the development of flashlamp pumped high energy and high power Q-switched laser systems especially for biomedical applications. Over the last decade, the advancement of higher brightness laser and light-emitting diodes in the red spectral region, generated a renewed interest towards Alexandrite [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] and continuous-wave laser output powers above 25 W have already been achieved from compact diode-pumped systems [12]. Mode-locking of Alexandrite using Saturable Bragg Reflectors (SBRs) [26], Kerr-lensing [27,28], and graphene saturable absorbers [29] has also been demonstrated recently.…”