Kelly Sidebands Research Articles

Passively mode‐locked soliton fiber laser using a combination of saturable absorber and nonlinear polarization rotation technique

AbstractAll‐fiber passively mode‐locked (ML) soliton fiber laser is demonstrated based on the combination of two ML mechanisms, single wall carbon nanotube saturable absorber, and nonlinear polarization rotation.The gain medium is a 10‐m long erbium‐doped fiber, which is pumped by a 980‐nm laser diode in a ring configuration. A stable soliton laser is succesfully achieved using the filter, which functions to reshape and maintain the soliton pulse in the cavity. It operates at 1588 nm with a repetition rate of 8.3 MHz and a pulse width of 0.79 ps. The output spectrum shows strong Kelly sidebands indicating that the pulse duration is near the minimum possible value. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1430–1432, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26850

Direct generation of 128-fs Gaussian pulses from a compensation-free fiber laser using dual mode-locking mechanisms

We have experimentally demonstrated the direct generation of 128-fs pulses in an all-anomalous-dispersion all-fiber mode-locked laser. The laser is free of dispersion compensation in the cavity based on standard single mode fiber (SMF). The time-bandwidth product is 0.536. The laser is achieved by using two mode-lockers, one is nonlinear polarization rotation (NPR), and the other is nonlinear amplifying loop mirror. The coexistence of dual mode-locking mechanisms can decrease the cavity length to 12-m, and also results in producing high-quality pulses with a Gaussian shape both on the pulse profile and spectrum, but without Kelly sidebands.

Subpicosecond thin-disk laser oscillator with pulse energies of up to 259 microjoules by use of an active multipass geometry

The pulse shaping dynamics of a diode-pumped laser oscillator with active multipass cell was studied experimentally and numerically. We demonstrate the generation of high energy subpicosecond pulses with a pulse energy of up to 25.9 microJ at a pulse duration of 928 fs directly from a thin-disk laser oscillator. These results are achieved by employing a selfimaging active multipass geometry operated in ambient atmosphere. Stable single pulse operation has been obtained with an average output power in excess of 76 W and at a repetition rate of 2.93 MHz. Self starting passive mode locking was accomplished using a semiconductor saturable absorber mirror. The experimental results are compared with numerical simulations, showing good agreement including the appearance of Kelly sidebands. Furthermore, a modified soliton-area theorem for approximating the pulse duration is presented.

Quantized separations of phase-locked soliton pairs in fiber lasers

We report the discovery of a quantization of the separation between phase-locked soliton pairs that is related to the radiation waves known as Kelly sidebands, in a passively mode-locked fiber ring laser. Our numerical simulations that predict this phenomenon have been confirmed by our experimental results.