Graphene filled optical fiber Fabry‐Pérot cavity tunable filter

Abstract

Before saturated absorption, graphene possesses optical nonlinear refractive index, which is a photoinduced refractive index effect. Taking advantage of this effect, a wavelength tunable filter is realized based on a graphene filled all optical fiber Fabry‐Pérot microcavity. Experimental results show that the interference wavelength of the filter exhibits linear red‐shift with the increase of the tunning optical power and tunning efficiency increases with the increase of cavity length and filled graphene thickness. In this study, the maximum wavelength vs power tunning efficiency can get 66 pm/mW. This filter has the advantages of high tunning efficiency, simple structure, antienvironmental interference good mechanical performance, and repeatability.

A 1.33–1.88 GHz microfluidically tunable filter with controllable coupling

“…Therefore, the tunable filter has attracted people's attention due to its features of wide tuning frequency coverage and multifrequency support. [1][2][3] In the past, the tuning technology about tunable filter was mainly realized through electrical control, including micro-electro-mechanical system (MEMS), [4][5][6] varactor, 7,8 agile material, [9][10][11] and so on.…”

“…With the rapid development of wireless communication technology and the increasingly saturation of spectrum resources, it is difficult for traditional filters to meet people's needs because of their fixed resonant frequencies and bandwidths. Therefore, the tunable filter has attracted people's attention due to its features of wide tuning frequency coverage and multifrequency support 1–3 . In the past, the tuning technology about tunable filter was mainly realized through electrical control, including micro‐electro‐mechanical system (MEMS), 4–6 varactor, 7,8 agile material, 9–11 and so on.…”

Bandwidth‐reconfigurable microwave photonic filter based on stimulated Brillouin scattering effect spreading by vector modulation technology

“…Microwave photonic filters (MPFs) attracted persistent attentions because of its potential to overcome inherent limitations of electrical signal processing, such as reconfigurability and tunability 1,2 . Among all MPFs, rectangular response is always highly desired to keep highest signal fidelity and filter out most of unwanted noise 3,4 . MPFs based on stimulated Brillouin scattering (SBS) effect could achieve rectangular responses with the exact flat top and sharp edges by vector modulation and selected wanted signal by Brillouin amplification 5 .…”