Fig. 1. (a) Schematic of a phased array consisting of two laser waveguides,
A and
B, with each of width
2a and an edge-to-edge separation of
2d. (b) More details about the distribution of refractive indices
n1,2, where
g represents gain per unit length and
α the background attenuation coefficient per unit length due to effects such as scattering and intervalence band absorption [
43].
Fig. 2. Stability diagrams of the solitary phased array in the (d/a, γNΔΩ/2π) plane for (a)–(d) P=1.1Pth and (e)–(h) P=2Pth. (a), (e) Purely real index, (b), (f) positive index guiding with gain-guiding, (c), (g) pure gain-guiding, and (d), (h) index antiguiding with gain-guiding. Blue (yellow) stands for stability (instability).
Fig. 3. Modulation frequency response of the solitary phased array at P=1.1Pth. (a) Purely real index with d/a=2.4, (b) positive index guiding with gain-guiding with d/a=1.35, (c) pure gain-guiding with d/a=1.25, and (d) index antiguiding with gain-guiding with d/a=1.01. Red (blue) represents in-phase (out-of-phase) modulation.
Fig. 4. Modulation frequency response of the solitary phased array at P=2Pth. (a) Purely real index with d/a=1.75, (b) positive index guiding with gain-guiding with d/a=1.3, (c) pure gain-guiding with d/a=1.05, and (d) index antiguiding with gain-guiding with d/a=0.91. Red (blue) represents in-phase (out-of-phase) modulation.
Fig. 5. Modulation frequency response of the solitary phased array at (a), (b) P=1.1Pth and (c), (d) P=2Pth for index antiguiding with gain-guiding. (a), (b) d/a, 0.5–1.01 and (c), (d) d/a, 0.5–0.91. (a), (c) In-phase modulation and (b), (d) out-of-phase modulation.
Fig. 6. Modulation frequency response of the solitary phased array for (a), (b)P=1.1Pth and d/a=0.97, as well as (c), (d) P=2Pth and d/a=0.87 in the case of index antiguiding with gain-guiding. (a), (b) γNΔΩ/2π, 0 to −9 GHz and (c), (d) γNΔΩ/2π, 0 to −10 GHz. (a), (c) In-phase modulation and (b), (d) out-of-phase modulation.
Fig. 7. Modulation frequency response of the solitary phased array for (a) P=1.1Pth and d/a=1.01, as well as (b) P=2Pth and d/a=0.91 in the case of index antiguiding with gain-guiding. Red (blue) represents laser A(B). Here only laser A is modulated.
Fig. 8. Stability diagrams of the optically injected phased array in the (K, Δf) plane for (a) P=1.1Pth and d/a=1.01, as well as for (b) P=2Pth and d/a=0.91 in the case of index antiguiding with gain-guiding. Blue (yellow) stands for stability (instability).
Fig. 9. Modulation frequency response of the optically injected phased array for different detuning frequencies Δf and a fixed injection ratio K=200 in the case of index antiguiding with gain-guiding, where (a), (b) P=1.1Pth and d/a=1.01, as well as (c), (d) P=2Pth and d/a=0.91. (a), (c) In-phase modulation and (b), (d) out-of-phase modulation.
Fig. 10. Modulation frequency response of the optically injected phased array for different injection ratios K and a fixed detuning frequency Δf=0 GHz in the case of index antiguiding with gain-guiding, where P=2Pth and d/a=0.91. (a) In-phase modulation and (b) out-of-phase modulation.
Fig. 11. Modulation frequency response of the optically injected phased array for (a) P=2Pth and (b) P=5Pth in the case of index antiguiding with gain-guiding. (a) K=160 and (b) K=250. Other parameters are d/a=0.91 and Δf=20 GHz. Red (blue) represents in-phase (out-of-phase) modulation. Horizontal dashed line corresponds to the −3 dB level.
Fig. 12. Modulation frequency response of the master-amplitude-modulated optically injected phased array for different injection ratios K and a fixed detuning frequency Δf=20 GHz in the case of index antiguiding with gain-guiding. Other parameters are P=2Pth and d/a=0.91. Horizontal dashed line corresponds to the −3 dB level.
| | | | | | | (rad) | 0.00097 | 87.7 | 0 | 1.26 | 0 | 0.844 | 83.6 | 0 | 0.0005 | 90.6 | 0.000937 | 1.09 | 0.896 | 0.817 | 90.2 | 0.233 | 0 | 99.3 | 0.00103 | 0.795 | 1.22 | 0.745 | 91.9 | 0.294 | −0.0005 | 108 | 0.00112 | 0.604 | 1.61 | 0.685 | 96.3 | 0.183 |
|
Table 1. Values of Key Parameters for Modeling, Using Material Parameter Values Given in Refs. [
43,
48]