All‐Optical Phosphorene Phase Modulator with Enhanced Stability Under Ambient Conditions

Abstract

All‐optical modulators, wherein signal light can be manipulated by another controlling light, have recently emerged as a promising perspective in all‐optical communications, interconnects and signal processing. Herein, by taking advantage of the strong light‐matter interaction and thickness‐dependent direct energy bandgap in few‐layer phosphorene, an all‐fiber all‐optical modulator based on a Mach–Zehnder interferometer comprising few‐layer fluorinated phosphorene‐deposited microfiber has been devised and further demonstrated with phase modulation ability. The phase shift of the signal light, capable of being converted into intensity modulation, could be readily controlled by the photothermal effect in phosphorene. A maximal phase shift of 8π is obtained at a control light of 290 mW, corresponding to a conversion efficiency of 0.029 π mW−1. The optical information carried by the control light is successfully copied towards the signal light with a modulation depth of 17 dB and a rise time constant of 2.5 ms. Stability under ambient conditions is enhanced significantly thanks to atomistic fluorination in phosphorene that can overcome drawbacks of easy oxidation of intrinsic phosphorene and maintain performance for a long term. This prototypical phosphorene‐based all‐optical phase modulator will have a great potential to be applied in all‐optical information processing and be integrated into optical fiber systems.

Boron Nanosheets for Efficient All‐Optical Modulation and Logic Operation

“…As for optical modulation, an indispensable technology for modern optical communication, controlling optical properties of a material by changing its refractive index is a widely adopted pathway . The refractive index of a material, however, is temperature dependent, which implies a way for optical modulation mediated by thermal control.…”

MZI‐Based All‐Optical Modulator Using MXene Ti3C2Tx(T = F, O, or OH) Deposited Microfiber

“…Meanwhile, for future optical networks, all‐optical devices have become the focus because of their easy integration, low loss, and good compatibility with optical fiber systems. The modulator accounts for a significant component in the application of optical connections . The all‐optical modulator with a materials‐based device has good prospects in optical communications and optical information processing fields.…”

“…Subsequently, all‐optical modulators with WS 2 ‐ and BP‐based devices were published. Because of the thermal effects of 2D materials, the maximum obtained phase shifts were 6π and 8π, and the rise time constants were 7.3 and 2.5 ms …”

Fiber all-optical light control with low-dimensional materials (LDMs): thermo-optic effect and saturable absorption

“…[4][5][6][7] Fiber all-optical light control utilizes mature ber technologies and allows alloptical devices to be compatible with current ber communication systems. Therefore, ber all-optical light control has attracted widespread research interests and many of the latest results have reported all-optical modulators, [8][9][10][11][12][13][14][15][16][17] phase shiers, 12,14,[17][18][19] logic gates, 12,14,20 and switches. 2,[5][6][7]15,18,19,[21][22][23] Meanwhile, LDMs have been a research hotspot because of their plentiful photonic and optoelectronic properties including graphene, 9,[24][25][26][27] graphene oxide, 28,29 carbon nanotubes (CNTs), [30][31][32] transition metal dichalcogenides (TMDs), [33][34][35] topological insulators (TIs), [36]…”

“…Many all-optical devices based on these two effects have been reported. [11][12][13][14]16,[18][19][20]62,[65][66][67][68] Therefore, it is very important to build up a complete view on the principle and performance of these devices.…”