Fiber-lasers for ultrafast optics

Few-cycle pulses from a graphene mode-locked all-fiber laser

“…The maximum temporal resolution is determined by the duration, ∆τ , of the pulse. This is usually defined as the full width at half maximum (FWHM) of its intensity profile in the time domain, I(t) [1]. Alternatively ∆τ may be defined by the number of oscillation periods of the electric field carrier wave (optical cycles) within the pulse[2] N = ∆τ T0 = ν 0 ∆τ , where T 0 is the optical cycle of frequency ν 0 .…”

“…In the visible and near infrared (NIR), T 0 lies, e.g, between 2fs at λ ∼600nm and 5fs at λ ∼1.5µm, which set the ultimate speed limit for devices operating in this wavelength range. Achieving shorter pulses therefore requires moving to shorter wavelengths.Pulses as short as 2-cycles can be generated directly from laser cavities using passive mode-locking [1][2][3]. Ti:Saphire lasers have become established tools for few-cycle generation [2], with the shortest pulses produced to date having ∆τ ∼5fs[4] at a centre wavelength, λ 0 ∼800nm, corresponding to less than 2-cycles, with spectral width ∆λ ∼600nm [4].…”

“…However, both Ti:Saphire oscillators and OPAs optimized to produce few-cycle pulses are complex and expensive setups, relying on bulk optics [2,9]. This has driven a research effort to find novel approaches, not only capable of producing short pulses, but also cheap, simple, broadband, and inexpensive, which would make few-cycle pulses more accessible to the wider scientific community.Compared to their solid-state counterparts, fiber lasers are attractive platforms for short pulse generation due to their simple and compact designs [10], efficient heat dissipation [11], and alignment-free operation [1,2,11]. These characteristics, combined with advances in glass technology [12,13] and nonlinear optics [14], resulted in systems working from the visible to the mid-infrared (MIR) [12].…”

“…Compared to their solid-state counterparts, fiber lasers are attractive platforms for short pulse generation due to their simple and compact designs [10], efficient heat dissipation [11], and alignment-free operation [1,2,11]. These characteristics, combined with advances in glass technology [12,13] and nonlinear optics [14], resulted in systems working from the visible to the mid-infrared (MIR) [12].…”

Strictly all-fiber picosecond ytterbium fiber laser utilizing chirped-fiber-Bragg-gratings for dispersion control

“…In recent years there has been an extensive growth in research activities focused on the development of ultrashort (<10ps) pulse sources based on rare-earth-doped-fibers [1]. This trend is motivated by the advantages of the short durations and high peak powers of ultrashort pulses for numerous practical applications.…”