2
A. Deyasi and A. Sarkar
property of rejecting the unwanted wavelength band of propagating e.m wave, due to
the formation of multiple forbidden regions, and also allows the desired spectra [6].
This unique feature leads to several new photonic devices in the form of transmitter
[7], receiver [8], waveguide [9], sensor [10], fibre [11], along with realization of nonlinear effect [12] and quantum information processing [13]. Though two-dimensional
[14] or three-dimensional photonic crystals [15] are experimentally realizable, most
of the devices, as of now, are made using one-dimensional structure [16–18]; henceforth, it is customary to investigate the optical properties offered by this structure in
further details. The properties of the devices are critically dependent on the material
composition [19] as well as dimensions of different layers [20], incident angles [21]
and mode of propagations [22]. In the next paragraph, we will briefly explain the role
of different materials used so far to fabricate devices and the importance of negative
index materials in this context.
Semiconductor heterostructures are recently being considered as a suitable composition for making photonic crystal [23], though dielectric combinations are
favoured because of less fabrication cost. Very recently, metamaterials or negative
refractive index materials are also considered to visualize the same [24], owing
to their established quality performance in antenna engineering [25], where they
exhibited improved SNR performance. Henceforth, it becomes the duty of design
engineers to check the performance of single negative index or double negative index
material-based optical devices, under the light of Bragg grating [26]. A few results
are recently reported [27, 28], which forces the workers for further investigation, as
the outcome is positive. Therefore, research is directed towards LHM-based photonic
crystal investigation, and computation of bandwidth becomes the first step of that
analysis.
2 Objective
In the present chapter, the design of optical bandpass filter with one-dimensional
metamaterial–air-based photonic crystal has been studied for transmissivity characteristics of optical filter. Generally, two different metamaterials with refractive index
−4 and −0.3 have been introduced in photonic crystal in air [29]. The former is the
nanofishnet structure having shape of the internal void as elliptical in nature, and
the latter is termed as paired nanorod. Both the materials are well-established and
already physically realizable; henceforth, they can safely be considered for analysis
purpose. Our aim is to study and compare the defected photonic crystal structure
with the ideal photonic crystal and also study that how the transmission property
of optical filter varies due to change in the angle of incidence, metamaterial length
and air thickness. Transmission properties have been analysed due to the variation of
these parameters for TE and TM mode, along with bandwidth variation [30]. From
this observation, we can select the photonic filter with which the refractive index is
better for practical application and for practical designing of optical bandpass filter
A. Deyasi and A. Sarkar
property of rejecting the unwanted wavelength band of propagating e.m wave, due to
the formation of multiple forbidden regions, and also allows the desired spectra [6].
This unique feature leads to several new photonic devices in the form of transmitter
[7], receiver [8], waveguide [9], sensor [10], fibre [11], along with realization of nonlinear effect [12] and quantum information processing [13]. Though two-dimensional
[14] or three-dimensional photonic crystals [15] are experimentally realizable, most
of the devices, as of now, are made using one-dimensional structure [16–18]; henceforth, it is customary to investigate the optical properties offered by this structure in
further details. The properties of the devices are critically dependent on the material
composition [19] as well as dimensions of different layers [20], incident angles [21]
and mode of propagations [22]. In the next paragraph, we will briefly explain the role
of different materials used so far to fabricate devices and the importance of negative
index materials in this context.
Semiconductor heterostructures are recently being considered as a suitable composition for making photonic crystal [23], though dielectric combinations are
favoured because of less fabrication cost. Very recently, metamaterials or negative
refractive index materials are also considered to visualize the same [24], owing
to their established quality performance in antenna engineering [25], where they
exhibited improved SNR performance. Henceforth, it becomes the duty of design
engineers to check the performance of single negative index or double negative index
material-based optical devices, under the light of Bragg grating [26]. A few results
are recently reported [27, 28], which forces the workers for further investigation, as
the outcome is positive. Therefore, research is directed towards LHM-based photonic
crystal investigation, and computation of bandwidth becomes the first step of that
analysis.
2 Objective
In the present chapter, the design of optical bandpass filter with one-dimensional
metamaterial–air-based photonic crystal has been studied for transmissivity characteristics of optical filter. Generally, two different metamaterials with refractive index
−4 and −0.3 have been introduced in photonic crystal in air [29]. The former is the
nanofishnet structure having shape of the internal void as elliptical in nature, and
the latter is termed as paired nanorod. Both the materials are well-established and
already physically realizable; henceforth, they can safely be considered for analysis
purpose. Our aim is to study and compare the defected photonic crystal structure
with the ideal photonic crystal and also study that how the transmission property
of optical filter varies due to change in the angle of incidence, metamaterial length
and air thickness. Transmission properties have been analysed due to the variation of
these parameters for TE and TM mode, along with bandwidth variation [30]. From
this observation, we can select the photonic filter with which the refractive index is
better for practical application and for practical designing of optical bandpass filter