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Schematic view of a 2D PC with square lattice composed of square air rods in the background medium of dielectric.
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We calculate the lifetime distribution function of an assembly of polarized atoms in two-dimensional (2D) photonic crystals (PCs) at different polarization orientations of atomic dipole moments. We reveal a switching effect of atomic spontaneous emission (SE) and find a significant change of atomic lifetime, up to a factor of 33, by tuning the pola...
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We experimentally demonstrate a multiwavelength fiber laser (MWFL) based on bidirectional Lyot filter. A semiconductor optical amplifier (SOA) is used as the gain medium, while its combination with polarization controllers (PCs) and polarization beam combiner (PBC) induces intensity dependent loss (IDL) mechanism. The IDL mechanism acts as an inten...
Citations
... 5(a, b)] [162]. The Purcell effect also provides possibilities for tailoring polarization by air holes of PC defects [164][165][166]. The single photon emission with linear polarization was achieved in the point defect by designing a PBG only for transverse-electric-like modes [125]. ...
Single-photon source in micro- or nanoscale is the basic building block of on-chip quantum information and scalable quantum network. Enhanced spontaneous emission based on cavity quantum electrodynamics (CQED) is one of the key principles of realizing single-photon sources fabricated by micro- or nanophotonic cavities. Here we mainly review the spontaneous emission of single emitters in micro- or nanostructures, such as whispering gallery microcavities, photonic crystals, plasmon nanostructures, metamaterials, and their hybrids. The researches have enriched light-matter interaction as well as made great influence in single-photon source, photonic circuit, and on-chip quantum information.
... The density of electromagnetic modes at a given frequencyVthe local density of states (LDOS)Vis reduced inside the photonic band gap and increased near the band edges. With an active medium present inside a PhC, it is possible to tune the emission characteristics of the active medium cleverly in certain frequency ranges depending on the extent of overlap of the emission band with the photonic stopband [4]- [8]. ...
Recently, we experimentally demonstrated room-temperature lasing of selfassembled opal photonic crystal (PhC) made of rhodamine-B-doped polystyrene colloids. Here, we explain this experimental observations by analyzing the phenomenon of light amplification in dye-activated PhCs via a complex-valued permittivity of the colloids. We show that the lasing is facilitated by the enhanced distributed feedback due to the reduced group
velocity in the vicinity of the photonic band edge. This simple approach to the analysis of PhC lasing behavior allows us to calculate the lasing wavelength in close agreement with the experimental value. It also enables the estimation of gain coefficient required for lasing and may prove useful in design of compact PhC-based lasers.
... A large amount of work, both theoretical and experimental, has been devoted to analyze the PBG structure and to use this structure to control SE precisely [16][17][18][19][20][21][22]. ...
... Certainly, to expand the ␦ function and smooth the curve is an approximation approach; however, when the considered atoms have a large density in the system, this approximation is ignorable [21,28,29]. ...
We present a type of confined one-dimensional photonic crystal (1D PC) that is composed of a 1D PC confined by perfect conductor boundaries in the lateral directions of the 1D PC. The dispersion relations are derived using the classical electromagnetic approach, and the photonic density of states and local photonic density of states are calculated numerically. It is found that the combined action of the periodic modulation and the quantization of wave vectors in the lateral directions may give rise to photonic bandgaps and sharp peaks in the photonic density of states, which provides us with an effective way to control the spontaneous emission (SE). Based on this, the SE is investigated by the lifetime distribution function. The numerical results show that there is a wide lifetime distribution with the coexistence of accelerated and inhibited decay processes of the SE.
... 6 Two-dimensional photonic crystal layers ͑2D-PCLs͒ have been extensively fabricated using GaAs and Si semiconductors that can be considered high refractive index dielectric materials for light propagation in the near infrared region. 7,8 2D-PCLs have been studied for a large variety of applications such as control of spontaneous emission, 9,10 plasmon assisted optics, 11,12 and so on. ...
In this work we fabricate 2D Photonic crystals layers (2D-PCL) in antimony-based films using Holographic Lithography. The antimony-based films present high refractive indexes that can be varied from 1.8 to 2.4, depending on the film composition, thus they are interesting materials for fabrication of 2D-PCL. Taking into account the geometry of the fabricated structures, the band diagrams and gap maps were calculated using 2D Finite Elements Method. By measuring the transmittance as a function of the wavelength for several angles symmetry of the 2D-PCL, it is possible to obtain the experimental band diagram. The experimental results are in good agreement with theoretical calculations of band diagram of the structure.
Photonic bandgaps (PBGs) in conventional one-dimensional (1-D) photonic crystals (PhCs) composed of isotropic dielectrics are polarization-insensitive since the optical length within a isotropic dielectric layer is polarization-independent. Herein, we realize polarization-sensitive PBGs in hybrid 1-D PhCs composed of all-dielectric elliptical metamaterials (EMMs) and isotropic dielectrics. Based on the Bragg scattering theory and iso-frequency curve analysis, an analytical model is established to characterize the angle dependence of PBGs under transverse magnetic and transverse electric polarizations. The polarization-dependent property of PBGs can be flexibly controlled by the filling ratio of one of the isotropic dielectrics within all-dielectric EMMs. Assisted by the polarization-sensitive PBGs, high-performance polarization selectivity can be achieved. Our work offers a loss-free platform to achieve polarization-sensitive physical phenomena and optical devices.
The influence of laser beam on the transmittance properties of anomalous dispersion photonic crystals （PCs） is investigated. Our calculations show that the pass band of anomalous dispersion PCs is tunable when altering the electron population in the atomic ground state of the anomalous dispersion material by the optical pumping method. With circularly polarized pump light, a huge Faraday rotation can be achieved under weak light intensity. Tunable pass band of anomalous dispersion PCs may lead to important technological applications in the optically controlled optical switch.
The strong confined electromagnetic field in the micro/nano photonic structures brings new opportunities for the research of interaction between light and matter. By designing optical modes, light can be controlled to realize reversible or inreversible energy exchange between photons and emitters at the micro/nano scale. Here, we review the basic principles of the interaction between light and matter in cavity quantum electrodynamics and their recent advances in strong coupling based on micro/nano photonic structures such as plasmon nanostructures, whispering gallery resonators and photonic crystals. These works opening the research of quantum nanophotonics will have great influence on the on-chip quantum devices and quantum informations.
The spontaneous emission rate and the energy level shift of a quantum dot in any micro-nanostructures can be expressed by the classical dyadic Green's function. However, the real part of the dyadic Green's function is divergent, when the source point and the field point are at the same position. This leads to an unphysical divergent level shift. Theoretically, the dyadic Green's function can be decomposed into a homogeneous part and a scattering part. Traditionally, the homogeneous field contribution is introduced into the definition of the transition frequency and the only need is to consider the effect of the scattering part which is non-divergent. Another renormalization method is to average the Green tensor over the volume of the quantum dot. In this work, a finite element method is proposed to address this problem. The renormalized dyadic Green function is expressed by the averaged radiation field of a point dipole source over the quantum dot volume. For the vacuum case, numerical results of the renormalized Green tensor agree well with the analytical ones. For the nanosphere model, the renormalized scattering Green tensor, which is the difference between the renormalized Green tensor and the analytical renormalized one in homogeneous space, agrees well with the analytical scattering Green tensor in the center of the quantum dot. Both of the above models clearly demonstrate the validity and accuracy of our method. Compared with the previous scattering Green function method where two different finite element runs are needed for one frequency point, our renormalization method just needs one single run. This greatly reduces the computation burden. Applying the theory to a gap plasmonic nano-cavity, we find extremely large modifications for the spontaneous emission rate and the energy level shift which are independent of the size of the quantum dot. For frequency around the higher order mode of the nano-cavity, spontaneous emission enhancement is about Γ/Γ0≈2.02×10⁶ and the energy level shift is about Δ≈1000 meV for a dipole moment 24D. These findings are instructive in the fields of quantum light-matter interactions.
The influence of laser beam on the transmittance properties of anomalous dispersion photonic crystals (PCs) is investigated. Our calculations show that the pass band of anomalous dispersion PCs is tunable when altering the electron population in the atomic ground state of the anomalous dispersion material by the optical pumping method. With circularly polarized pump light, a huge Faraday rotation can be achieved under weak light intensity. Tunable pass band of anomalous dispersion PCs may lead to important technological applications in the optically controlled optical switch.
We present an efficient method for calculating the orientation-dependent local density of states (ODLDOS) or local density of states (LDOS) in two-dimensional photonic crystals by combining the lattice point group transformation of the vector field and the special point integral with an interpolation method. This method can swiftly compute LDOS or ODLDOS and acquire the same results as those computed based on a larger number of k points in the first Brillouin zone. Our method improves the calculation speed by about 1000 times.
