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Metal oxide semiconductor (MOS) gas sensors operated at room temperature (RT) hold great promise for environmental monitoring in the emerging smart society. An in-depth understanding of the gas/MOS interfacial charge exchange under the ambient moist atmosphere is essential for subsequent molecule recognition. Herein, delafossite p-CuScO2 with a unique oxygen intercalation property was utilized. Eight orders of resistance tuning could be rationally achieved via controlling oxygen intercalation realized by air annealing (without altering the size and morphological properties), which allows extraction of both the intrinsic (gas/MOS interaction, p-type response) and extrinsic (gas/H2O/MOS interaction, pseudo-n-type response) sensing mechanisms upon exposure to ammonia molecules. This work could provide an insight into the underlying sensing mechanism of RT sensors working in an ambient moist atmosphere, and the unique n- to p-type switching contains rich molecule related features that could be potentially explored for molecule recognition.

Exploring novel ammonia sensors operated at room temperature holds great promise for various applications. Herein, we synthesized p-type delafossite AgAlO2 nanoparticles via hydrothermal method. The nanoparticles show a single Ag-deficient 3R delafossite phase with particle size between 200 and 500 nm. The sensor based on AgAlO2 nanoparticles exhibits high sensitivity, fast response-recovery and good selectivity to 100 ppm ammonia at 293 K 20–70 %RH. More interestingly, the sensor shows a pseudo n-type response to ammonia at 293 K 35 %RH, but a p-type sensing behavior at elevated temperature of 573 K. The temperature-dependent pseudo n-type response to ammonia gas is ascribed to the competition of extrinsic and intrinsic sensing behaviors, which resulted from the reaction of ammonia gas with surface adsorbed water molecules and adsorbed oxygen ions, respectively. The former can regulate the conduction of the adsorbed water layer, which contributes to the total conductivity as an external part, while the latter can modulate the intrinsic conductivity of the sensor by changing the hole concentration of AgAlO2. This work might provide a new idea to design low temperature gas sensors.

p-type ternary oxides can be extensively explored as alternative sensing channels to binary oxides with diverse structural and compositional versatilities. Seeking a novel approach to magnify their sensitivities toward gas molecules, e.g., volatile organic compounds (VOCs), will definitely expand their applications in the frontier area of healthcare and air-quality monitoring. In this work, delafossite CuCrO2 (CCO) nanoparticles with different grain sizes have been utilized as p-type ternary oxide sensors. It was found that singly ionized oxygen vacancies (Vo•) defects, compared with the grain size of CCO nanoparticles, play an important role in enhancing the charge exchange at the VOCs molecules/CCO interface. In addition to suppressing the hole concentration of the sensor channel, the unpaired electron trapped in Vo• provides an active site for chemisorptions of environmental oxygen and VOCs molecules. The synergetic effect is responsible for the observed increase of sensitivity. Furthermore, the sensit...

Pure phase CuFeO 2 powders with specific surface area of 6.5 m 2 g −1 were synthesized by a self-combustion glycine nitrate process. The powders show a coral-like network structure with a wall thickness of about 100 nm and pore sizes ranging from tens of nanometers to hundreds of nanometers in diameter. The CuFeO 2 powders were first applied as photocathodes for p-type dye-sensitized solar cells with coumarin 343 as sensitizer and iodide/triiodide (I − /I 3 − ) as redox mediator. The sintering process and thickness of the CuFeO 2 photocathode films were roughly optimized. The optimized CuFeO 2 based solar cell has achieved the best open circuit voltage of 365 mV under 1 Sun AM 1.5 illumination. This record is significantly high in comparison to p-DSSCs based on NiO or other delafossites tested in the similar LiI/I 2 electrolyte solutions. This is mainly due to the much deeper valence band (0.69 V vs . NHE) of CuFeO 2 than that of the commonly used NiO (0.54 V vs . NHE).

Metal oxide semiconductor (MOS) gas sensors operated at room temperature (RT) hold great promise for environmental monitoring in the emerging smart society. An in-depth understanding of the gas/MOS interfacial charge exchange under the ambient moist atmosphere is essential for subsequent molecule recognition. Herein, delafossite p-CuScO

It has very important application value to investigate the damage mechanism of CaF2 windows irradiated by ultraviolet excimer laser. As significant optical materials, CaF2 windows have been widely used in the ultraviolet photoelectrical field. Because the ultraviolet excimer laser presents favorable characteristics such as short wavelength and high photon energy, the high power excimer lasers are expected to be widely applied in precision laser machining and military field. In this paper, the experiment on damage in CaF2 windows irradiated by 248nm ultraviolet excimer laser was carried out. The damage characteristics of irradiated spots under different experiment conditions were detected by optical microscope. The laser induced damage thresholds of CaF2 windows were calculated by the zero damage probability through linear fitting. The damage mechanism of CaF2 windows were discussed based on the surface characteristics of damage spots. The experimental results indicated that the damage thresholds of zero probability for the 248nm excimer laser to CaF2 windows were 5.6J/cm2 of the incident surface, and 1.1J/cm2 of the exit surface respectively. When CaF2 windows was irradiated by 248nm excimer laser, its damage first occurred to its exit surface, the damage threshold of exit surface was smaller than that of incident surface. As the laser fluence increased gradually, the damage of exit surface was shown to grow exponential and its degree was significantly higher than that of incident surface. This work is helpful to further improve damage resistance of CaF2 windows in high power laser facility. It can provide the necessary references for selection of ultraviolet optical materials and optimization of application.

Identifying the defect type which closely correlates with gas/metal oxide semiconductor (MOS) interfacial charge exchange is of utmost importance for rationally designing high performance MOS gas sensors, which are essential for the emerging sensing electronics for assessing the personal health and environment pollution. Herein, we report the sensing performance of p-type NiO toward volatile organic compounds (VOCs) molecules could be drastically improved by Sc dopant. At an optimal doping ratio of 7.4 at.%, the sensor response to 100 ppm acetone was boosted from 8.2 (pure NiO) to 109.4, with a low detection limit of 10 ppb. Comprehensive defect characterizations indicate surface unsaturated oxygen vacancy (VO) defects act as active sites that facilitate the interfacial charge exchange at elevated temperatures. Our work highlights that abundant VO defects induced by aliovalent Sc dopant play an important role in boosting the sensitivity of p-type NiO toward VOCs, and provide valuable guidance in designing high performance p-type MOS sensors.

Iron pyrite (FeS2) has been proved to be one of the most promising materials for counter electrodes (CEs) of dye-sensitized solar cells (DSSCs) due to its excellent electrocatalytic properties. In this report, high purity FeS2 powders were synthesized through hydrothermal method, and the effect of NaOH addition on crystal size and electrocatalytic activities of FeS2 was investigated. With the addition of NaOH, the size of FeS2 particles decreased, and the electrocatalytic activity of the FeS2 CEs and the DSSCs performance were improved significantly. Under simulated solar light irradiation with intensity of 100 mW cm−2 (AM 1.5), the DSSCs based on FeS2 CEs with NaOH addition achieved a power conversion efficiency of 5.78%.

Transparent conducting amorphous p-type CuFeO2 (CFO) thin film was prepared by radio-frequency (RF) magnetron sputtering method at room temperature using polycrystalline CuFeO2 target. Amorphous structure of as-deposited film was confirmed by XRD. XPS analysis convinced that the chemical state of Cu+ and Fe3+ in the film, and the chemical composition of the thin films is close to the stoichiometry of CuFeO2. Surface morphology of the film was analysed by SEM studies. p-type nature and concentration of carriers was investigated by Hall effect measurement. The p–n heterojunction in the structure of Al/n-Si/p-CuFeO2/Al showed good rectifying behaviour with a forward and reverse currents ratio of 555 at 2 V. The turn-on voltage and reverse leakage current values were found to be 0.9 V and 4 μA at −2 V. Further, the conduction mechanism of forward bias voltage was controlled by thermionic emission (TE) and trap-space charge limited current (TCLC) mechanisms.

The role of remnant PbI2 in CH3NH3PbI3 films is still controversial, some investigations have revealed that the remnant PbI2 plays a passivation role, reduces the charge recombination in perovskite solar cells (PSCs), and improves the performance of PSCs, but the opposing views state that remnant PbI2 has no passivation effect and it would deteriorate the stability of the devices. In our investigation, the CH3NH3PbI3 films have been prepared by a two-step spin-coating method and the content of the remnant PbI2 in CH3NH3PbI3 films has been tuned by varying the preparation temperature. It has been found that increasing the heating temperature could increase the coverage of spin-coated PbI2 films, which has led to high coverage CH3NH3PbI3 films and more remnant PbI2 in CH3NH3PbI3 films, and as a result, the performance of PSCs was enhanced obviously and the maximum power conversion efficiency of 14.32 ± 0.28% was achieved by the PSCs prepared at 130/120 °C (PbI2 films were heated at 130 °C and CH3NH3PbI3 films were heated at 120 °C). Furthermore, the dark current, electrochemical impedance spectroscopy and time-resolved fluorescence emission decay measurements revealed that the charge recombination in PSCs has been gradually suppressed and the fluorescence emission lifetime has gradually increased with the content of remnant PbI2 increasing. Thus, the passivation effects of the unreacted and decomposed PbI2 in improving the performance of PSCs have been confirmed unquestionably.

CuCr 0.97 Mg 0.03 O 2 thin films were prepared by direct current magnetron sputtering under various percentage of oxygen flow rate (P O ) followed by post-annealed in N 2 atmosphere. The microstructures, optical and electrical properties of the films were investigated. The film deposited in pure Ar atmosphere showed pure CuCrO 2 phase, while the films deposited in O 2 and Ar mixture atmosphere showed CuO and CuCr 2 O 4 mixture phase. After post-annealed at 800 °C, the films deposited in O 2 and Ar mixture atmosphere turned into c-axis oriented single-phase CuCrO 2 which showed much better transparency and electrical conductivity than the film deposited in pure Ar. The film deposited in P O = 40% with thickness of 350 nm showed the lowest resistivity of 0.4 Ω cm and transmittance over 60% in visible light region.

Exploring novel sensing materials with extraordinary specificity/selectivity is essential to construct artificial gas molecules recognition chips (sensor arrays) for future environment and health monitoring. Herein, we reported the excellent H2S sensing properties of a p-type delafossite CuAlO2 sensor. Without complex size, morphology or defect control procedures, irregularly shaped CuAlO2 particles (size ranging from tens of nm to several μm) synthesized by a simple sol-gel route, exhibit an ultrahigh response (4600) toward (10 ppm) H2S molecules at 160 °C. Tiny responses (

The laser-induced damage threshold of a calcium fluoride (CaF2) single crystal was obtained by a 193 nm ArF excimer laser. The damage morphology of the crystal was analyzed. The results showed that the surface of CaF2 single crystal broke along the natural cleavage plane under ArF excimer laser irradiation, some fragments fell off, and Newton’s rings were observed on the curved fragments. Laser-induced periodic stripe structures (LIPSS) appeared on the surface layer beneath the fragments that peeled off. The spacing of LIPSS was measured, and the formation mechanism of LIPSS was analyzed based on the interference model.

p-type ternary oxides can be extensively explored as alternative sensing channels to binary oxides with diverse structural and compositional versatilities. Seeking a novel approach to magnify their sensitivities toward gas molecules, e.g., volatile organic compounds (VOCs), will definitely expand their applications in the frontier area of healthcare and air-quality monitoring. In this work, delafossite CuCrO

Amorphous CuFeO 2 thin films were prepared on Al 2 O 3 (001) substrates by radio-frequency magnetron sputtering method at room temperature. Various oxygen partial pressures P O in the sputtering gas ambient (9.1%, 11.1% and 13.0%) were used in the deposition experiments. X-ray photoelectron spectroscopy analysis convinced the chemical state of Cu + and Fe 3 + in the films, and the chemical compositions of the thin films are close to the stoichiometry of CuFeO 2 . The content of oxygen composition increased systematically with increasing P O . From the optical transmission spectra, only one absorption edge could be observed during 200–1200 nm for all the films with a band gap around 3.25 eV. This result is different from the polycrystalline CuFeO 2 films which have 3 absorption edges in the range of 200–1200 nm. This interesting result indicates that amorphous CuFeO 2 thin films have much different electronic energy band with polycrystalline ones. The resistivity of the films first decreases and then increases with increasing P O . The minimum resistivity of 4.2 Ω cm with optical transmittance of 47% at 600 nm is obtained for the film deposited in P O = 11.1%.

Single phase CuFeO 2 thin films with c-axis orientation were prepared by RF sputtering method at room temperature under oxygen partial pressure P O from 5% to 15% and then post annealed at 900 °C for 4 h in flowing N 2 atmosphere. The grains of the films show layer-by-layer structure and are closely gathered and densely arranged. The E g at near-UV region shows a redshift with increment of P O which may due to the impurity levels induced by oxygen interstitials. The resistivity of the films first decreased and then increased with increasing P O . The minimum resistivity of 0.32 Ωcm at room temperature for the sample 10%-PA is nearly two-order magnitude smaller than that (18 Ωcm) for 5%-PA. Oxygen interstitial doping can effectively enhance the conductivity of CuFeO 2 thin films.

Vacuum thermal evaporated Cu x S (VTE-Cu x S) film on fluorine-doped tin oxide substrate has been investigated as counter electrode (CE) for quantum dot-sensitized solar cells (QDSCs) with polysulfide electrolyte. The photovoltaic parameters of QDSCs show an obvious dependence on the annealing time of Cu x S film, and the maximum power conversion efficiency of 3.16 ± 0.05% under one sun illumination (100 mW cm −2 , AM 1.5 G) was obtained when the VTE-Cu x S CE was annealed at 270 °C for 300 s (VTE-Cu x S-300s CE). Electrochemical impedance spectroscopy, Tafel polarization, and cyclic voltammetry measurements have been employed to investigate the electrocatalytic activity of VTE-Cu x S-300s CE. The electrocatalytic activity of the VTE-Cu x S-300s CE is much higher than that of Pt CE, and is slightly higher than that of Cu 2 S CE in situ prepared on brass sheet. In particular, VTE-Cu x S-300s CE holds high diffusion velocity of S 2− /S n 2− in polysulfide electrolyte, and the stability of its electrocatalytic activity in polysulfide electrolyte is better than that of Pt and Brass-Cu 2 S CEs obviously.

The anatase TiO 2 nanoparticle films with different thicknesses have been fabricated through screen printing method, and CdS and CdSe quantum dots (QDs) have been deposited on TiO 2 films in turn through successive ionic layer adsorption and reaction (SILAR) method. It has been found that the amount of QDs decreases significantly and the size of QDs increases obviously with the depth increasing in TiO 2 nanoparticle films, and the size distribution of QDs shifts to large-size direction with the TiO 2 film thickness increasing. Furthermore, a qualitative model of CdS/CdSe quantum dot distribution in TiO 2 nanoparticle films has been obtained. After optimizing the TiO 2 film thickness, the quantum dot-sensitized solar cells (QDSCs) with about 10 μm thick nanocrystalline TiO 2 electrodes and Pt counter electrodes have reached relatively high power conversion efficiencies of 3.26 ± 0.10% under one sun illumination (100 mW cm −2 , AM 1.5 G).

Single phase delafossite CuFeO2 thin films were synthesized by a simple sol–gel method. The influence of polyethylene glycol (PEG) on the morphology and optoelectronic properties of the films was studied by addition of 1.0 g PEG in 10 ml precursor solution. The crystal sizes of the derived CuFeO2 films with and without addition of PEG were 49 nm, but the sample with addition of PEG (labeled as CFO-PEG) showed weaker c-axis orientation growth. The sample without addition of PEG (labeled as CFO) showed a compact surface without detectable pores and had a thickness around 50 nm. However, the sample CFO-PEG exhibited a porous surface with worm-like grains in nanometric scale and had a thickness around 310 nm. Enhanced absorbance in UV–vis region was observed for the sample CFO-PEG which might ascribe to both the thickness and porous surface. The optical direct bandgaps at near-UV were estimated to be ~3.0 and 3.38 eV for the sample CFO-PEG and CFO, respectively. Though the porous surface of CFO-PEG has improved the absorbance in UV–vis region, the resistivity has also been increased due to the homogeneous distribution of interspaces between the worm-like grains, which makes the incident photon to current efficiency of CFO-PEG lower than that of CFO.

CuFe1−xMgxO2 (0 ⩽ x ⩽ 0.05) thin films were synthesized by a simple sol–gel method. The structural and optoelectronic properties of the films were studied. Single phase CuFeO2 thin films with c-axis orientation were obtained on sapphire substrates and secondary phase was not detected by XRD measurements in the studied doping range. The resistivity of the films first decreased and then increased with increasing x. The minimum resistivity was observed as 3.23 Ω cm at room temperature for the doping amount of x = 0.02. The transmittance of all the films was around 37% in the wavelength of 600 nm and three absorb edges were observed in the wavelength range of 200–1100 nm. The optical direct bandgaps of CuFeO2 were estimated to be ∼3.38 eV, 2.04 eV and 1 eV, respectively.

TiCl 4 solution growth has been introduced to modify the single-crystal rutile TiO 2 nanorod arrays (TNRs) used as photoanodes of dye-sensitized solar cells (DSSCs). After modification, a large number of rutile TiO 2 nanoparticles have been synthesized on the surface of TNRs. The surface area and dye adsorption of these modified TNRs increase obviously, and their photovoltaic performance improves significantly. The maximum energy conversion efficiency of 4.14 ± 0.07% has been obtained when the concentration of TiCl 4 solution is 0.2 M and the growth time is 36 h. To obtain similar energy conversion efficiencies the single-crystal TNRs based DSSCs need far less amount of dye than P25 TiO 2 nanoparticles based DSSCs. Contrary to previous publications, the electron transport rate of bare and modified single-crystal rutile TNRs with one-dimensional nanostructures is slower than that of P25 TiO 2 nanoparticles film. But the increase of the electron recombination lifetime of the bare and modified single-crystal rutile TNRs compensates for the slower electron transport rate, and makes them have similar charge-collection efficiencies to that of P25 TiO 2 nanoparticles based DSSCs.

The 248 nm excimer laser etching characteristic of alumina ceramic and sapphire had been studied using different laser fluence and different number of pulses. And the interaction mechanism of 248 nm excimer laser with alumina ceramic and sapphire had been analyzed. The results showed that when the laser fluence was less than 8 J/cm 2 , the etching depth of alumina ceramic and sapphire were increased with the increase of laser fluence and number of pulses. At the high number pulses and high-energy, the surface of the sapphire had no obvious melting phenomenon, and the alumina ceramic appeared obvious melting phenomenon. The interaction mechanism of excimer laser with alumina ceramics and sapphire was mainly two-photon absorption. But because of the existence of impurities and defects, the coupling between the laser radiation and ceramic and sapphire was strong, and the thermal evaporation mechanism was also obvious.

The flexible TiO2 photoelectrodes were fabricated by coating P25 (TiO2 nanoparticles; Degussa, Germany, a mixture of ca. 30% rutile and 70% anatase) paste on ITO-PEN substrates using doctor-blade method. The photoelectrodes were treated by cold isostatic pressing method under different pressure. The interconnection of nanoparticles and mechanical adhesion between the films and the substrates were improved under high pressure. The photovoltaic performances of the flexible dye-sensitized solar cells (DSSCs) were remarkably correlative to pressure. The DSSCs employing the flexible 300 MPa-pressed TiO2 photoelectrodes achieved conversion efficiency as high as 2.06% under AM 1.5 simulated sunlight. By replacing the solvents of the paste, the efficiency of the cell was improved to 2.87%. (C) 2011 Elsevier B.V. All rights reserved.

Delafossites CuY 1− x Ca x O 2 (0 ≤ x ≤0.10) ceramics have been prepared by solid state reaction using Cu 2 O, Y 2 O 3 and CaCO 3 . Liquid phase sintering, which obviously accelerates the reaction speed of Cu 2 O–Y 2 O 3 –CaCO 3 system and promotes the formation of CuYO 2 phase is evidenced for the Ca-doped samples. During the sintering process, CuO can react with CaO to form two intermediate compounds, CaCu 2 O 3 and Ca 2 CuO 3 , which decompose into CaO and liquid phase during 1273–1323 K. In the dopant range of 0 ≤ x ≤0.10, both electrical conductivity and density of the samples are increased by Ca-doping. The room temperature conductivity of CuY 0.94 Ca 0.06 O 2 is more than four orders of magnitude higher than that of CuYO 2 .

The structural, electrical and optical properties of Nb-doped ZnO films were investigated with different Nb contents (0, 0.15, 0.31, 0.46, 0.62, and 0.94 at.%) in this article. The film with 0.46 at.% Nb content showed the lowest resistivity of 8.95 × 10 − 4 Ω cm and high transmittance about 80% with high c -axis orientation. The undoped ZnO film showed a semiconducting behavior. And Nb-doped ZnO films showed a metal-semiconductor transition (MST), which was connected with localization of degenerate electrons. The films showed metallic conductivity at temperatures closer to the ambient temperature and semiconducting behavior at lower temperatures. It was noted that the NZO films with much lower Nb concentration of 0.15 at.% presented MST compared with other transparent conducting oxides films.

Basing on some growth models of thin film, we have investigated the growth mechanism of glancing angle deposition (GLAD) film. The simulation verifies that the overhangs/vacancies also contribute to the columnar growth as well as the self-shadowing effect for GLAD thin film. Besides, we have studied the effect of the deposition rate, surface and bulk diffusions on the microstructure of thin film using the time-dependent Monte Carlo method. The results show that the surface and bulk diffusions can significantly enhance the packing density of thin film in GLAD growth, and the increase of the deposition rate induce the moderate decrease of the packing density. (c) 2006 Elsevier B.V. All rights reserved.

ZrO2 thin films were prepared on BK7 glass substrates by electron beam evaporation deposition method. The influence of deposition rate varying from 1.2 to 6.3 nm s(-1) on surface morphology and other properties of ZrO2 films were examined. With increasing deposition rate, the surface defect density increased. The decrease in half width at full maximum in X-ray diffraction pattern with deposition rate indicates an increase in crystal dimension with increasing deposition rate. Electron beam deposited ZrO2 films are known to be inhomogeneous. From the change of the peak transmittance value, it can be deduced that the inhomogeneity of ZrO2 films strengthened gradually with increasing deposition rate. The type of surface defects changed from nodules to craters when the deposition rate was high enough.

In (2 + 1) dimension, growth process of thin film on non-planar substrate in Kuramoto–Sivashinsky model is studied with numerical simulation approach. 15 × 15 semi-ellipsoids arranged orderly on the surface of substrate are used to represent initial rough surface. The results show that at the initial stage of growth process, the surface morphology of thin film appears to be grid-structure, and the interface width constantly decreases with the growth time, then reaches minimum. However, the grid-structure becomes ambiguous, and granules of different sizes distribute evenly on the surface of thin film with the increase of growth time. Thereafter, the average size of granules and the interface width gradually increase, and the surface morphology of thin film presents fractal properties. The numerical results of height–height correlation functions of thin film verify the surface morphology of thin film to be fractal for a longer growth time. By fitting of the height–height correlation functions of thin film with different growth times, the growth process is described quantitatively.

Based on Maxwell's equations, standard boundary conditions are imposed on resultant electric- and magnetic-field vectors at interfaces, and the propagating characteristics of extraordinary waves, such as the forward- and backward-propagating directions of wave vectors, rays and their corresponding refractive indices are determined in a uniaxially birefringent thin film. Furthermore, 2 x 2 characteristic matrices of a birefringent thin film are derived including multiple reflections for the extraordinary wave.

In this paper a non-polarizing beam splitter design concept is presented using anisotropic thin films. Transmittance of s- and p-polarized waves can be dealt with separately. This concept can be applied to non-polarizing beam splitter designs of single wavelength and broad-band spectrum at oblique incidence. A few examples of non-polarizing beam splitters (50:50) at the design wavelength of 1064 nm and over the visible spectrum (420 nm–680 nm) are elaborated. Besides, the angular performance of these designs is examined.

A series of zirconium dioxide films were grown on rough borosilicate crown glass substrates with reactive ion beam sputtering technique. The evolution of the surface roughness was studied in the smoothing and roughening growth regimes using atomic force microscopy. By quantitative analysis of surface morphology, the interface width of the growth fronts was found to have a minimum during the deposition process. Dynamic scaling was observed for thicker films; the roughness exponent was found to be in the range of 0.7–0.9 and the growth exponent at approximately 0.4.

CdSe/CdS semiconductor quantum dots co-sensitized TiO2 nanostructure (nanoflower, nanowire, nanorod, nanotube) photoanodes on Ti substrate were fabricated. Among these different nanostructures, the nanotube based QDSC has the best performance.

TiCl4 modification increased the power conversion efficiency of single-crystal rutile TiO2 nanorod arrays (TNRs) based quantum dot-sensitized solar cells from 0.36% to 1.17%. Vacuum thermal evaporated CuxS counter electrode was introduced for TNRs based QDSCs.

The theoretical model of K9 glass irradiated by a 248-nm KrF excimer laser was established, and a numerical simulation was performed to calculate temperature and thermal stress fields in the K9 glass sample using the finite element method. The laser-induced damage thresholds were defined and calculated, and the effect of repetition frequency and the number of pulses on the damage threshold were also studied. Furthermore, the experiment research was carried out to confirm the numerical simulation. The damage threshold and damage morphology were analyzed by means of a metallurgical microscope and scanning electron microscopy. The simulation and experimental results indicated that the damage mechanism of K9 glass irradiated by a KrF excimer laser was melting damage and stress damage, and the stress damage first appeared inside the K9 glass sample. The tensile stress damage threshold, the compressive stress damage threshold, and the melting damage threshold were 0.64, 0.76, and 1.05 J/cm2, respectively. The damage threshold decreased with increasing repetition frequency and number of laser pulses. The experimental results indicated that the damage threshold of K9 glass was 2.8 J/cm2.

As the principal section consistent with the principal plane, electromagnetic propagation in a uniaxially birefingent thin film can be described with a concise 2 × 2 characteristic matrix, in which the refractive indices of the forward and backward propagating extraordinary rays are different and dependent. In this letter, based on Huygen's construction, the refractive indices and effective optical admittances of the forward and backward propagating extraordinary rays are discussed further, and the 2 × 2 characteristic matrix is simplified. Furthermore, the input optical admittance, reflectance and transmittance of assembly is presented, just as an isotropic thin film. The result can be extended to the general case of multilayer uniaxially birefringent thin films with their optic axes in the incident plane.