We demonstrate output pulse energies of 20 nJ from an erbium-doped fiber oscillator that contains only positive dispersion fibers and is mode locked by use of nonlinear polarization evolution and stabilized with a birefringent filter. The fiber oscillator operates at a repetition rate of 3.5 MHz with a central wavelength of 1550 nm. The positively chirped output pulses have a duration of 53 ps and are compressed to 750 fs. The large positive chirp of the output pulses and the steep side edges of the pulse spectrum indicate dissipative soliton operation.

No abstract

No abstract

We investigate the scaling properties of mode-locked all-normal dispersion fiber oscillators in terms of output pulse energy and compressed pulse duration. Experimental results are achieved by stepwise variation of the resonator dispersion, total fiber length, and the spectral filter bandwidth. Adjustment of these parameters enables pulse duration scaling down to 31 fs and increase of output pulse energy up to 84 nJ.

We present a mode-locked, all-normal-dispersion erbium-doped fiber oscillator generating output pulses with broadband spectra covering the range from 1475 to 1620 nm. The oscillator operates at a repetition rate of 109 MHz with output pulse energies of 1.6 nJ. Mode-locked operation is achieved by use of nonlinear polarization evolution in combination with a birefringent filter. The output pulses are dechirped with an external prism compressor to a duration of 50 fs.

The debate and controversy concerning the momentum of light in a dielectric medium (Abraham vs Minkowski) is well-known and still not fully resolved. In this paper, we investigate the origin of both momenta in the frame of special relativity by considering photons in media as relativistic quasiparticles. We demonstrate for the first time to the best of our knowledge that the Minkowski form of the photon mass, momentum, and energy follows directly from the relativistic energy conservation law. We introduce a new expression for the momentum of light in a dispersive medium, consistent with the experimentally observed propagation of photons at the group velocity. Finally, the effect of light-induced optical stretching is discussed, which can be used for experimental verification of the existing expressions for the photon momentum.

We present a wavelength-tunable, external-cavity GaSb-based quantum-well laser operating near 3.2 µm. The laser setup consists of an intra-cavity grating in Littman-Metcalf configuration and a cascade pumped GaSb-based gain chip with a narrow-ridge waveguide. The narrow-ridge waveguide has a length of 2 mm and width of 7.5 µm. Cascade pumping is realized with three type-I quantum-wells, using one quantum-well per cascade stage. The laser provides continuous-wave output powers up to 8 mW and slope-efficiencies of 13 % at room temperature. Laser operation is demonstrated over a wavelength range of more than 300 nm, using continuous-wave and pulsed operation regimes.

No abstract