196 resultados para mode-locked lasers
em Cambridge University Engineering Department Publications Database
Resumo:
We develop an analytical theory of high-power passively mode-locked lasers with a slow absorber; the theory is valid at pulse energies well exceeding the saturation energy. We analyze the Haus modelocking master equation in the pulse-energy-domain representation, approximating the intensity profile function by a series in the vicinity of its peak value. We consider the high-power operation regime of subpicosecond blue-violet GaN mode-locked diode lasers, using the approach developed. © 2010 Springer Science+Business Media, Inc.
Resumo:
A detailed study of the design issues relevant to long-wavelength monolithic mode-locked lasers is presented. Following a detailed review of the field, we have devised a validated travelling wave model to explore the limits of mode-locking in monolithic laser diodes, not only in terms of pulse duration and repetition rate, but also in terms of stability. It is shown that fast absorber recovery is crucial for short pulse width, that the ratio of gain to absorption saturation is key in accessing ultrashort pulses and that low alpha factors give only modest benefit. Finally, optimized contact layouts are shown to greatly enhance pulse stability and the overall operational success. The design rules show high levels of consistency with published experimental data.
Resumo:
Ultrafast passively mode-locked lasers with spectral tuning capability and high output power have widespread applications in biomedical research, spectroscopy and telecommunications [1,2]. Currently, the dominant technology is based on semiconductor saturable absorber mirrors (SESAMs) [2,3]. However, these typically have a narrow tuning range, and require complex fabrication and packaging [2,3]. A simple, cost-effective alternative is to use Single Wall Carbon Nanotubes (SWNTs) [4,10] and Graphene [10,14]. Wide-band operation is possible using SWNTs with a wide diameter distribution [5,10]. However, SWNTs not in resonance are not used and may contribute to unwanted insertion losses [10]. The linear dispersion of the Dirac electrons in graphene offers an ideal solution for wideband ultrafast pulse generation [10,15]. © 2011 IEEE.
Resumo:
We compare experimental results showing stable dissipative-soliton solutions exist in mode-locked lasers with ultra-large normal dispersion (as large as 21.5 ps2), with both the analytic framework provided by Haus' master-equation and full numerical simulations. © 2010 Optical Society of America.
Resumo:
Sub-picosecond tunable ultrafast lasers are important tools for many applications. Here we present an ultrafast tunable fiber laser mode-locked by a nanotube based saturable absorber. The laser outputs ∼500fs pulses over a 33 nm range at 1.5μm. This outperforms the current achievable pulse duration from tunable nanotube mode-locked lasers. © 2012 Elsevier B.V. All rights reserved.
Resumo:
We compare experimental results showing stable dissipative-soliton solutions exist in mode-locked lasers with ultra-large normal dispersion (as large as 21.5 ps2), with both the analytic framework provided by Haus' master-equation and full numerical simulations. © 2010 Optical Society of America.