Carbon nanotube films for ultrafast broadband technology

Abstract

Mode-locked sub-picosecond operation of Yb-, Er- and Tm:Hodoped fiber lasers operating at 1.05 microm, 1.56 microm and 1.99 microm, respectively, is demonstrated using the same sample carbon nanotube-based saturable absorber mirror. A mesh of single-walled carbon nanotubes was deposited on an Ag-mirror using a one-step dry-transfer contact press method to combine broadband saturable absorption and high reflectance properties. The novel fabrication method of the polymer-free absorber and device parameters determined using nonlinear reflectivity measurement are described in detail. To our knowledge the observed operation bandwidth of approximately 1 microm is the broadest reported to date for a single carbon nanotube-based saturable absorber.

Carbon nanotubes for ultrafast fibre lasers

“…mirror coating [64]. The polymer-free CNT layer on a highly reflective Ag mirror enabled the building of a robust and compact linear cavity laser.…”

“…There are numerous reports in the literature [50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66][67] on the use of SWNTs as mode lockers and Q-switches for ultrafast lasers in the broad wavelength band, which are summarised in Table 1. One of the main advantages of SWNT-based SAs, apart from ultrashort relaxation time and high nonlinearity, is the ease of their fabrication and implementation into the laser setup.…”

“…One of the main advantages of SWNT-based SAs, apart from ultrashort relaxation time and high nonlinearity, is the ease of their fabrication and implementation into the laser setup. Typically, SWNT-based SAs are made of a solution [54,64], or deposited on the surface of optical parts [53,55] or SWNT-polymer composites [57-59, 61, 66], which will be discussed hereafter in detail.…”

A stable, wideband tunable, near transform-limited, graphene-mode-locked, ultrafast laser

“…In CNTs the diameter controls the bandgap, thus, defining the operating wavelength. Broadband tunability is possible using CNTs with a wide diameter distribution [14,36,37]. However, when operating at a particular wavelength, CNTs not in resonance are not used and give insertion losses.…”

Continuous Wave and Pulsed Erbium-Doped Fiber Lasers for Microwave Photonics Applications

“…The Bragg wavelength is directly proportional to the grating period, so great flexibility in setting the wavelength emission of a DFB laser is accomplished when writing Bragg gratings. The most widespread methods to inscribe Bragg gratings in optical fibers are the two-beam interferometric method [44] and the phase mask method [45,46], both based on the irradiation of periodic patterns of UV light upon photosensitive fibers.…”