Chaotic optical power dropouts driven by low frequency bias forcing in a mid-infrared quantum cascade laser

Abstract

Mid-infrared quantum cascade lasers operating under external optical feedback and external periodic bias forcing are shown to exhibit a deterministic chaotic pattern composed of frequencies which are linked to the one of the forcing. Results also show that both the amplitude and the frequency of the forcing play a key role in the number of retrieved spikes per modulation period. These findings are of paramount importance for chaotic operation of quantum cascade lasers in applications such as optical countermeasure systems and secure atmospheric transmission lines, as well as for simulating neuronal systems and the communication between neurons due to sudden bursts.

Investigation of Chaotic and Spiking Dynamics in Mid-Infrared Quantum Cascade Lasers Operating Continuous-Waves and Under Current Modulation

“…These are, to the best of our knowledge, the first results reporting on the nonlinear dynamics of QCLs emitting right in the transparency window between 8.5 µm and 11 µm. Similar results with a Type 1 QCL have already been reported [38]. Fig.…”

“…The higher the frequency, the lower the number of spikes and the lower the amplitude, the lower the number of spikes. Other results with a Type 1 QCL showed that the value of the continuous pump that is applied prior to the periodic modulation has very small influence on the number of spikes per period [38]. If the periodic forcing is not a sine wave but a square wave, like shown in Fig.…”

Extreme events in quantum cascade lasers

“…In this case, the chaotic dropouts synchronize with the periodic modulation, and the number of spikes per periods can vary through a modification of the amplitude of the modulation or the frequency of the modulation. 28 Analyzing the spiking dynamics showed that some configurations led to spikes with a magnified amplitude. The amplitude of these spikes is very sensitive to any change of the parameters, as shown in In this configuration, the amplitude of the modulation corresponds to 28% of the pumping current.…”

“…20 This chaotic pattern is composed of intensity dropouts, called low-frequency fluctuations (LFFs), and experiments showed that an extensive control of these spikes was possible under a periodic excitation. 28 In this work, we experimentally build up a nonlinear dynamical setup to show the first extreme events emitted by a mid-infrared QCL operating under external feedback. In addition to that, we also describe several methods to trigger those events with a maximum success rate of 47%.…”

“…The setup we used in this experimental work is exactly the same as that widely described in Ref. 28 and is recalled in Fig. 1.…”