31 research outputs found
Phase locking of coupled lasers with many longitudinal modes
Detailed experimental and theoretical investigations on two coupled fiber
lasers, each with many longitudinal modes, reveal that the behavior of the
longitudinal modes depends on both the coupling strength as well as the
detuning between them. For low to moderate coupling strength only longitudinal
modes which are common for both lasers phase-lock while those that are not
common gradually disappear. For larger coupling strengths, the longitudinal
modes that are not common reappear and phase-lock. When the coupling strength
approaches unity the coupled lasers behave as a single long cavity with
correspondingly denser longitudinal modes. Finally, we show that the gradual
increase in phase-locking as a function of the coupling strength results from
competition between phase-locked and non phase-locked longitudinal modes.Comment: 3 pages, 4 figures, submitted to opt. let
Fiber amplification of radially and azimuthally polarized laser light
The results on amplifying either radially or azimuthally polarized light with
a fiber amplifier are presented. Experimental results reveal that more than 85%
polarization purity can be retained at the output even with 40dB amplification,
and that efficient conversion of the amplified light to linear polarization can
be obtained.Comment: 3 pages, 4 figures, submitted to optics letter
Coherent addition of two dimensional array of fiber lasers
Configurations for efficient free space coherent addition of four separate
fiber lasers arranged in two dimensional array are presented. They include
compact and robust interferometric combiners that can be inserted either inside
or outside the cavity of the combined lasers system. The results reveal that
over 85% combining efficiency can be obtained.Comment: To be published in Optics Communicatio
How synchronized human networks escape local minima
Finding the global minimum in complex networks while avoiding local minima is
challenging in many types of networks. We study the dynamics of complex human
networks and observed that humans have different methods to avoid local minima
than other networks. Humans can change the coupling strength between them or
change their tempo. This leads to different dynamics than other networks and
makes human networks more robust and better resilient against perturbations. We
observed high-order vortex states, oscillation death, and amplitude death, due
to the unique dynamics of the network. This research may have implications in
politics, economics, pandemic control, decision-making, and predicting the
dynamics of networks with artificial intelligence.Comment: 13 pages, 5 figure
Waveguide-based single-shot temporal cross-correlator
We describe a novel technique for performing a single-shot optical
cross-correlation in nanowaveguides. Our scheme is based on four-wave mixing
between two orthogonally polarized input signals propagating with different
velocities due to polarization mode dispersion. The cross-correlation is
determined by measuring the spectrum of the idler wave generated by the
four-wave mixing process.Comment: 7 pages, 6 figures, Submitted to Optics Expres