Polarization synchronization in unidirectionally coupled vertical-cavity surface-emitting lasers with orthogonal optical injection (original) (raw)
Related papers
Optics letters, 2016
Polarization switching in a long-wavelength vertical-cavity surface-emitting laser (VCSEL) under parallel optical injection is analyzed in a theoretical and experimental way. For the first time, to our knowledge, we report experimentally a state in which injection locking of the parallel polarization and excitation of the free-running orthogonal polarization of the VCSEL are simultaneously obtained. We obtain very simple analytical expressions that describe both linear polarizations. We show that the power of both linear polarizations depend linearly on the injected power in such a way that the total power emitted by the VCSEL is constant. We perform a linear stability analysis of this solution to characterize the region of parameters in which it can be observed. Our measurements qualitatively confirm the previous theoretical predictions.
Journal of The Optical Society of America B-optical Physics, 2017
We investigate experimentally and theoretically the polarization switching found in a single-transverse mode VCSEL when subject to parallel optical injection. Our analysis focuses on a recently observed state in which injection locking of the parallel polarization and excitation of the free-running orthogonal polarization of the VCSEL are obtained. A simple nonlinear dependence between the power of both linear polarizations and the frequency detuning is found. Also the total power emitted by the VCSEL is constant and independent on the injected optical power and on the frequency detuning. We check these results experimentally for a variety of frequency detunings and bias currents applied to the device. We report experimental and theoretical stability maps in the injected power-frequency detuning plane for different bias currents identifying the regions in which the state is observed. A simple analytical expression that describes the map boundary for large and negative frequency detunings is obtained. This provides a simple method to extract the linear dichroism of the device.
Journal of the Optical Society of America B, 2011
We present an experimental and theoretical study of the polarization and time-resolved nonlinear dynamics of a long-wavelength single-mode linearly polarized vertical-cavity surface-emitting laser (VCSEL) subject to orthogonal optical injection. Special attention is paid to the correlation properties of both linear polarizations emitted by the VCSEL. We measure simultaneous time traces of both linearly polarized output signals for several values of the bias current, the strength of the optical injection, and the frequency detuning between master and the free-running VCSEL. Different dynamical regimes, including periodic, period doubling, and irregular dynamics, are observed for both polarizations. For positive frequency detuning we usually find that the orthogonal polarization is the only polarization that contributes to the dynamics of the total power. Only for large values of the bias current and for small values of the optical injection strength, near the border of the periodic region, have we found correlated periodic dynamics in both linear polarizations. For negative frequency detuning we find anticorrelated dynamics in both linear polarizations. The average and dispersion of the time between consecutive pulses that appear in the anticorrelated regime increase with the injected power. The irregular dynamics, characterized by broadened power spectra, is related to large values of the dispersion of the time between pulses. A good overall qualitative agreement is found between our theoretical and experimental results.
2011
The authors have studied the effects of polarised optical injection in a 1550 nm vertical-cavity surface-emitting laser (VCSEL) operated at currents up to 4.5 times threshold. Regions of stable injection locking have been measured for cases where the injected signal is polarised to match one of the two polarisations of the fundamental transverse mode of the solitary VCSEL. In addition regions of polarisation switching have been found for the case where the input polarisation is matched to that of the subsidiary mode of the solitary ...
Optical injection induced polarization mode switching and correlation analysis on a VCSEL
arXiv: Optics, 2015
Vertical cavity Surface Emitting Laser (VCSEL) diodes emit light in two polarization modes. The amount of optical feedback is found to influence the intensities of the emitted modes. We investigate the effect of the amount of total output polarization feedback and polarization selective feedback on the intensities of the two emitted polarization modes. A 40 micro seconds resolution time series correlation analysis is done for different feedback conditions and investigate the power spectral continuity and onset of chaos on two polarization modes
Injection locking and polarization switching in a 1550-nm VCSEL under parallel optical injection
2015
We report an experimental study of the injection locking regime and the polarization switching in a single mode Vertical-Cavity Surface-Emitting laser (VCSEL) under parallel optical injection when we inject around the parallel polarization frequency of the solitary VCSEL. We have analyzed the results for high and low injected values of the power. Also we have analyzed the effect of decreasing and increasing the frequency detuning for a fixed value of the injected power. Different bistable behaviors have been observed depending on the value of the injected power.
IEEE Journal of Quantum Electronics, 2007
In this paper, we report on theoretical and experimental investigation on polarization and transverse mode behavior of vertical-cavity surface-emitting lasers (VCSELs) under orthogonal optical injection as a function of the injection strength and of the detuning between the injection frequency and the free-running frequency of the solitary laser. As the injection strength increases the VCSEL switches to the master laser polarization. We find that the injection power necessary to obtain such polarization switching is minimum at two different values of the frequency detuning: the first one corresponds to the frequency splitting between the two linearly polarized fundamental transverse modes, and the second one appears at a larger positive frequency detuning, close to the frequency difference between the first-order and the fundamental transverse modes of the solitary VCSEL. We show theoretically that both the depth and the frequency corresponding to the second minimum increase when the relative losses between the two transverse modes decrease. Bistability of the polarization switching is obtained for the whole frequency detuning range. Such a bistability is found for the fundamental mode only or for both transverse modes, depending on the value of the detuning. The theoretical and experimental optical spectra are in good agreement showing that the first-order transverse mode appears locked to the external injection.