Static and Dynamic Properties of Coherently-Coupled Photonic-Crystal Vertical-Cavity Surface-Emitting Laser Arrays

Supermode Switching in Coherently-Coupled Vertical Cavity Surface Emitting Laser Diode Arrays

“…Since the out-of-phase supermode is observed at threshold, we know that 𝜅 𝑖 >0 and after the supermode switches to in-phase, 𝜅 𝑖 is negative [9,14]. Supermode switching and bistability in 2-element coherent VCSEL arrays has been previously noted [15,17]. The simple anti-guided supermode model and the expected change in the index profile across the array as current is injected, described in the previous section, explains this mode switching phenomenon.…”

“…In this section, we discuss the experimental results and observations on our coherently coupled 2-element VCSEL array. The output power, near-field intensity, and far-field profile can be measured as a function of the two bias currents, which can be used to characterize the coherent properties of the arrays [5,17]. We first identify the coherently coupled region from the enhanced output optical power as well as array emission into a single spectral peak, which occurs with approximately equal current injection into the elements.…”

“…By varying the injection currents to left (I Left ) and right (I Right ) VCSEL elements, we can create 3-dimensional color contour maps to aid analysis [5,17]. In Fig.…”

Complex Waveguide Supermode Analysis of Coherently-Coupled Microcavity Laser Arrays

“…C OHERENTLY coupled 2-element arrays of photonic crystal vertical cavity surface emitting lasers (VCSELs) have been shown to exhibit novel dynamic properties such as increased small-signal modulation bandwidth [1,2], enhanced digital data transmission [3], and reduced intensity noise and harmonic distortion [4]. When coherently coupled, the photonic crystal VCSEL arrays emit into non-Hermitian supermodes [5] that exhibit beam steering [6] and exceptional points [7].…”

Dynamics of Evanescently-Coupled Laser Pairs With Unequal Pumping: Analysis Using a Three-Variable Reduction of the Coupled Rate Equations

“…HE study of small arrays of coupled semiconductor lasers, especially those with independent control of pumping for each element [1][2][3][4], is an area which is receiving increasing interest and attention. For the case of VCSEL arrays this has been driven by attractive properties including phase front engineering and beam-steering [5,6], extended bandwidth [7,8] and enhanced digital modulation [9,4], with one exemplar application being the prospect of tunable ultrafast photonic oscillators [10,11]. At the fundamental level, such arrays have been shown to exhibit non-Hermiticity [12,13], exceptional points [13][14][15] and parity-time symmetry breaking [1].…”