Two channel highly sensitive sensors based on 4×4 multimode interference coupler

A microring resonator with the multimode interference coupler is fabricated on the polymer platform by using UV-based soft nanoimprint technique. A unique class of fluorinated polymer, perfluoropolyether (PFPE), is employed for the fabrication of the flexible soft mold. By optimizing the proportion between Ormocore and the thinner maT, the microring resonator is fabricated almost without residual layer. The fabricated device with a Q-factor up to 2.3 × 104 is demonstrated for very-near-infrared wavelengths, which shows high potential for sensing applications.

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Reflection Enhancement and Giant Lateral Shift in Defective Photonic Crystals with Graphene

Applied Sciences ◽

10.3390/app9102141 ◽

2019 ◽

Vol 9 (10) ◽

pp. 2141 ◽

Cited By ~ 10

Author(s):

Dong Zhao ◽

Fangmei Liu ◽

Peng Meng ◽

Jie Wen ◽

Siliu Xu ◽

...

Keyword(s):

Photonic Crystals ◽

Interband Transition ◽

Single Layer ◽

Defect Layer ◽

Lateral Shift ◽

Single Layer Graphene ◽

Intraband Transition ◽

Highly Sensitive ◽

Highly Sensitive Sensors ◽

Periodic Number

This study investigates the reflectance of the defective mode (DM) and the lateral shift of reflected beam in defective photonic crystals incorporated with single-layer graphene by the transfer matrix method (TMM). Graphene, treated as an equivalent dielectric with a thickness of 0.34 nm, was embedded in the center of a defect layer. The reflectance of the DM was greatly enhanced as the intraband transition of electrons was converted to an interband transition in graphene. The reflectance of the DM could be further enhanced by increasing the Bragg periodic number. Furthermore, a large lateral shift of the reflected beam could also be induced around the DM. This study may find great applications in highly sensitive sensors.

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Unidirectional Invisibility Induced by Complex Anti-Parity–Time Symmetric Periodic Lattices

Applied Sciences ◽

10.3390/app9183808 ◽

2019 ◽

Vol 9 (18) ◽

pp. 3808 ◽

Cited By ~ 4

Author(s):

Hui Cao ◽

Dong Zhao ◽

Ming Fang ◽

Huang Guo ◽

Yonghong Hu ◽

...

Keyword(s):

Reflection Coefficient ◽

Parameter Space ◽

Frequency Band ◽

Angular Frequency ◽

Lateral Shift ◽

The Other ◽

Wide Frequency Band ◽

Highly Sensitive ◽

Highly Sensitive Sensors

Complex anti-parity-time symmetric periodic lattices, in a wide frequency band, can act as unidirectional invisible media. The reflection from one end is suppressed while it is enhanced from the other. Furthermore, unidirectional laser points (ULPs) which correspond to the poles of reflection from one end, arise in the parameter space composed of the permittivity and angular frequency. The phase of the reflection coefficient changes sharply near the ULPs. Subsequently, large lateral shift which is proportional to the slope of phase could be induced for the reflected beam. The study may find great applications in unidirectional invisibility, unidirectional lasers and highly sensitive sensors.

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