One-dimensional Quasiperiodic Photonic Crystals Research Articles

Polarization-independent wide-angle flexible multiband thermal emitters enabled by layered quasi-periodic photonic crystal

An efficient, flexible multi-band thermal emitter is proposed in the present work, consisting of a one-dimensional quasi-periodic photonic crystal and a reflective substrate. All the materials involved in the design have good high-temperature stability. Compared to absorbers with complex shapes, our planar devices are easier to fabricate, lithography-free, large-scale, and cost-effective fabrication. It is found that more and narrower absorption peaks will be generated when more layers of the quasi-periodic photonic crystal composite layer are placed on the top of the metal substrate. All three absorption peaks have the absorbance of more than 97% for the three-cell device we designed. Since the designed emitter has excellent substrate adaptability and is insensitive to polarization and incident angle, it is favourable to fabricate on flexible substrates. The present work may find promising applications in high-temperature and flexibility research areas such as infrared detection.

Photonic bandgap characteristics of GaAs/AlAs-based one-dimensional quasi-periodic photonic crystal

The optical behavior of GaAs/AlAs based 1D multi-layered quasi-periodic photonic crystal is investigated by employing the transfer matrix method (TMM). The complex dielectric constants are employed for analyzing the transmission spectra of the crystal at the long-wave limit. The numerical results are studied for different quasi-periodic sequential arrangements of GaAs/AlAs, which is also compared with the periodic structure. The major portion of optical spectra is affected by different generation numbers of quasi-periodic sequences as compared to the periodic crystal. The shifting of bandgaps around the central frequency with less optical-transmission peaks is observed within a considered frequency range. The mirrored or symmetrical behavior of two different superlattices remains unchanged with varying layer thickness. The scaling property is observed with the change in different incident angles. Moreover, generation number of different quasi-sequences plays a vital role to control the band-gap in the optical spectra. This study will be very helpful in designing the optical pass- and stop-band filters.

Transmittance properties of a quasi-periodic one-dimensional photonic crystals that incorporate nanocomposite material

In this paper, we investigate theoretically the transmission properties of one-dimensional quasi-periodic photonic crystals that containing nanocomposite material in the IR wavelength regions. Our structure is particularly designed using the Fibonacci role. Here, the nanocomposite material is composed of nanoparticles of Ag that are randomly immersed in a host dielectric material of SiO2. Numerical results are mainly investigated based on the well-known characteristic matrix method. The numerical results show the appearance of many photonic bandgaps due to the multiple periodicities of our structure. Furthermore, the effects of the parameters of the nanocomposite such as the volume fraction, the refractive index of the dielectric material and the size of the nanoparticles have distinct effects on the transmittance characteristics of our structure. Wherefore, the proposed structure could be considered the cornerstone for many applications such as multichannel filters and optical switches.

Effect of sequence built on photonic band gap properties of one-dimensional quasi-periodic photonic crystals: Application to Thue-Morse and Double-period structures

We elaborated by Radio frequency magnetron sputtering two types of one-dimensional quasi-periodic photonic crystals, based on Si/SiO2 materials, according to the Thue-Morse sequence and the Double-period one. We have investigated their optical properties, throughout the reflection transmission spectra, experimentally as well theoretically by using the transfer matrix method. The experimental spectra of these two structures are performed at normal incident light configuration, in the near infrared wavelengths range, and, are compared for the same number of layers, for a generation number N varying from 0 to 5, corresponding to a number of layers varying from 1 to 32, respectively. We experimentally put in evidence the appearance of photonic band gaps for N higher than 2, which are then well defined for N equal to 4, for the two structures. Furthermore, the results show that these two quasi-periodic structures exhibit sharp localized modes of light within the photonic band gaps, covering the optical telecommunication wavelengths 1.33 and 1.55 μm, with different number and position depending, on the built in distribution structures. The results also show a good agreement between the experimental and calculated spectra.

Effect of temperature on terahertz photonic and omnidirectional band gaps in one-dimensional quasi-periodic photonic crystals composed of semiconductor InSb.

Engineering of thermally tunable terahertz photonic and omnidirectional bandgaps has been demonstrated theoretically in one-dimensional quasi-periodic photonic crystals (PCs) containing semiconductor and dielectric materials. The considered quasi-periodic structures are taken in the form of Fibonacci, Thue-Morse, and double periodic sequences. We have shown that the photonic and omnidirectional bandgaps in the quasi-periodic structures with semiconductor constituents are strongly depend on the temperature, thickness of the constituted semiconductor and dielectric material layers, and generations of the quasi-periodic sequences. It has been found that the number of photonic bandgaps increases with layer thickness and generation of the quasi-periodic sequences. Omnidirectional bandgaps in the structures have also been obtained. Results show that the bandwidths of photonic and omnidirectional bandgaps are tunable by changing the temperature and lattice parameters of the structures. The generation of quasi-periodic sequences can also change the properties of photonic and omnidirectional bandgaps remarkably. The frequency range of the photonic and omnidirectional bandgaps can be tuned by the change of temperature and layer thickness of the considered quasi-periodic structures. This work will be useful to design tunable terahertz PC devices.

Lateral shift in one-dimensional quasiperiodic chiral photonic crystal

We investigate the lateral shift of a one-dimensional quasiperiodic photonic crystal consisting of chiral and conventional dielectric materials. The effect of structural irregularity on lateral shift is evaluated by stationary-phase approach. Our results show that the lateral shift can be modulated by varying the structural irregularity in quasiperiodic structure. Besides, the position of peak in lateral shift spectrum stays sensitive to the chiral factor of chiral materials. In comparison with that of periodic structure, quasiperiodic structure provides an extra degree of freedom to manipulate the lateral shift.

Multiple responses of TPP-assisted near-perfect absorption in metal/Fibonacci quasiperiodic photonic crystal

Absorption properties in one-dimensional quasiperiodic photonic crystal composed of a thin metallic layer and dielectric Fibonacci multilayers are investigated. It is found that a large number of photonic stopbands can occur at the dielectric Fibonacci multilayers. Tamm plasmon polaritons (TPPs) with the frequencies locating at each photonic stopband are excited at the interface between the metallic layer and the dielectric layer, leading to almost perfect absorption for the energy of incident wave. By adjusting the length of dielectric layer with higher refractive-index or the Fibonacci order, the number of absorption peaks can be tuned effectively and enlarged significantly.

10.1007/s11455-008-1007-9

The optical properties of one-dimensional quasiperiodic photonic crystals with linear profiles of modulation parameters are considered. It is shown that such systems possess a wider photonic band gap as compared to the ideal periodic system and can be used as omnidirectional reflectors. The asymmetric profiles of parameters in these systems results in the appearance of nonreciprocity of a new type that makes possible their use as the ideal, purely optical diodes.

Optical diodes and omnidirectional reflectors based on one-dimensional quasiperiodic photonic crystals

The optical properties of one-dimensional quasiperiodic photonic crystals with linear profiles of modulation parameters are considered. It is shown that such systems possess a wider photonic band gap as compared to the ideal periodic system and can be used as omnidirectional reflectors. The asymmetric profiles of parameters in these systems results in the appearance of nonreciprocity of a new type that makes possible their use as the ideal, purely optical diodes.

TRANSMISSION PROPERTIES OF QUASI-PERIODIC FIBONACCI ONE-DIMENSIONAL PHOTONIC CRYSTAL CONTAINING NEGATIVE PERMITTIVITY/PERMEABILITY MATERIAL

The transmission properties of one-dimensional quasi-periodic Fibonacci photonic crystal containing negative permittivity/permeability material are investigated by use of the transfer matrix method. We find that perfect transmission peaks exist at a series of dimensionless wavelength points in the transmission spectra, and the discrete localized modes appear inside the photonic band gap in the case of normal incidence. In the case of oblique incidence, the detailed numerical calculations show that the transmission peaks and angles strongly depend on the polarization of incident waves and the periodicity of the photonic crystals. In addition, we notice that the one-dimensional quasi-periodic photonic crystal can exhibit omni-directional reflection in a certain frequency region for all incident angles and polarizations. We also investigate the possibility of realizing the omni-directional reflection by means of the simple one-dimensional quasi-periodic Fibonacci photonic crystal.

Omnidirectional reflection from one-dimensional quasi-periodic photonic crystal containing left-handed material

In this Letter, we study the properties of one-dimensional quasi-periodic photonic crystal containing left-handed material. In the light of the dispersion relation, we show that one-dimensional quasi-periodic photonic crystal can exhibit complete reflection at a given microwave frequency for all incident angles and both polarizations ( s- and p-polarizations). The influence of left-handed material's permittivity and permeability on the omnidirectional reflection is also discussed. We find that when | ɛ | is larger than | μ | , it is difficult to realize the omnidirectional reflection for p-polarization, on the contrary, it is difficult to realize the omnidirectional reflection for s-polarization when | μ | is larger than | ɛ | , which is expected to realize omnidirectional reflection in a certain frequency region. The effect of the left-handed material's absorption on omnidirectional reflection is also investigated.