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This paper proposes an optical amplification method of measuring the minute displacement of a laser beam. The relationship between the displacement of the incident laser beam and the reflective bea...

Oxyfluoride silicate glasses co-doped with Cr3+ and Yb3+ ions were fabricated in this work. High △T (178–214 °C) value demonstrated that the thermal stability of the prepared glasses were better than tellurite and germanate glasses. X-ray diffraction (XRD) curves proved the amorphous nature of the glasses, the energy dispersive spectroscopy (EDS) analysis and Fourier Transform infrared spectroscopy (FT-IR) curves explored the network structure of glasses. The photoluminescence excitation (PLE) and photoluminescence emission (PL) spectra show that the glasses absorption peaks located at 430 nm (Cr3+:4A2g - 4T1g (P)) and 627 nm (Cr3+:4A2g - 4T2g), while the emission peak close to 1010 nm (Yb3+:2F5/2 -2F7/2), which meets the condition of energy down-conversion. Besides, the energy transfer efficiency (ηCET = 33.5%) and the quantum cutting efficiency (ηQE = 133.5%) were calculated from the measured decay curves. These values were higher than Cr3+/Yb3+ co-doped fluorosilicate glass with incorporating of CaF2 (21.5% and 123.5%) and Tb3+/Yb3+ oxyfluoride glass (13.5% and 113.5%), indicating the prepared samples are conducive to the energy transfer from Cr3+ to Yb3+ ions. The experimental results reveal that the oxyfluoride silicate glasses have potential application prospects in crystalline silicon (c-Si) solar cells.

Ho3+/Yb3+ co-doped tellurite–germanate glasses with lower phonon energy (771 cm−1) were prepared by conventional melt-quenching method. The prepared samples were characterized by emission spectra, differential scanning calorimeter (DSC) curve, X-ray diffraction (XRD) pattern, and Raman spectra. The DSC curve shows that the sample has a good thermal stability, in which the ΔT is 202 °C. Compared to the recently reported tellurite glasses, the ΔT was increased by approximately 24%. Under the 980 nm laser excitation, it was found that the full width at half maximum (FWHM) of the sample at 2.0 µm was 190 nm. Compared with the reported glasses for this type, the value was effectively improved. Meanwhile, the FWHM of the sample at 4.1 µm was 285 nm, which has not been reported yet. This indicates that Ho3+/Yb3+ co-doped tellurite–germanate glass has a great application prospect in mid-infrared broadband fiber amplifiers.

Titanium dioxide (TiO2) is of great interest as anode material for lithium-ion batteries (LIBs) because of its safety, structure stability, and low cost. However, the limitations of low conductivity and small theoretical capacity prevent its further applications. Herein, TiO2 nanospheres with a hollow structure (H-TiO2) were successfully synthesized via a hard-template method. The resultant material used as LIBs anode with superior lithium storage properties in terms of high initial capacity (∼289 mA h g−1 at 0.1 A g−1), good rate capability (∼101 mA h g−1 at 2 A g−1), and excellent cycling stability (∼196 mA h g−1 was retained over 300 cycles at 0.1 A g−1). The improved performances are attributed to the large specific area (~225 m2 g−1) and abundant mesoporous of the hollow structure, which can not only promote the diffusion of Li+ and e− but also achieve an increase in the contact area between electrodes and electrolyte.

Fluorotellurite glasses tri-doped with Tm 3+ , Er 3+ and Bi ions were investigated. The measured parameter ΔT (116 °C) confirmed that the prepared glasses had good stability. An ultra-broadband fluorescence emission (950–1670 nm) was observed with a full-width at half-maximum (FWHM) of 560 nm, which covered the entire bands of O, E, S, C, L and U. The 1800 nm fluorescence intensity of Tm 3+ /Er 3+ co-doped and Tm 3+ /Er 3+ /Bi tri-doped glasses was enhanced compared to Tm 3+ doped glass, which indicates that there is energy transfer between Tm 3+ , Er 3+ and Bi ions. The maximum fluorescence lifetime of the prepared glasses was 7.39 ms, indicating the excellent fluorescence performance at 1800 nm. Additionally, the maximum absorption cross section (σ abs = 1.77 × 10 −20 cm −2 ) and emission cross section (σ em = 7.61 × 10 −20 cm −2 ) suggest that the Tm 3+ /Er 3+ /Bi tri-doped glasses have good optical absorption properties and high gain fluorescence emission. The above results indicate that the Tm 3+ /Er 3+ /Bi tri-doped fluorotellurite glasses have good application prospects in the field of fiber amplifiers and near-infrared lasers.

Y2O3 and La2O3 co-doped silicate glasses were prepared by conventional melt-quenching method. The effects of Y2O3 and La2O3 contents on the structural, thermal and mechanical properties of glass samples were investigated by X-ray diffraction (XRD), Differential scanning calorimetry (DSC) and Fourier Transform Infrared Spectroscopy (FTIR). The results showed that the prepared glass samples exhibited excellent mechanical properties and thermal stability. The hardness, elastic modulus and ΔT reaches 860HV, 108 GPa and 299 °C, respectively. Compared with the reported glasses for this type, these values were increased by approximately 19.5%, 28% and 8.7%, respectively. In addition, the transmittance of all glass samples exceeds 90% in visible spectra range. The above results indicate that the prepared glass samples can be applied to the fields of architectural glass, automotive windshield and screen of electronic products.

2.7 μm fluorescence of Er3+ single doped glass and Er3+/Bi3+ co-doped glasses are obtained when excited by a 980 nm laser diode. The fluorescence emission intensity from Er3+ is enhanced significantly by doping Bi3+ in tellurite glass. In comparison with the single doped Er3+, the emission intensity increased by 17.8%. The measured parameter ΔT(154.8℃)＞130 ℃ indicates that compared with Er3+/Nd3+ co-doped tellurite glass and Tm3+ doped lead silicate glass, there is a better resistance to crystallization and thermal performance in Bi3+ doped tellurite glass. The enhanced 2.7 μm fluorescence emission of sample with the introduction of Bi3+, which may be caused by energy transfer between Bi3+ and Er3+.Above all, Strong 2.7 μm emission and good thermal properties reveal that the Bi3+/Er3+ co-doped glass may be a potential material to improve 2.7 μm laser performance of Er3+.

Smarting surface coatings have been shown to be good examples to cope with the drastic volume change and poor conductivity of SiO2 anode. Herein, we successfully synthesize the SiO2@a-TiO2@Ag composite with core–shell structure via a facile sol-gel method. The designed structure, in which a-TiO2 layer show elastic behavior, can alleviate the expansion of electrode, and provide more diffusion channels for lithium-ion. In addition, Ag nanoparticles are good conductor of electricity. The resulting materials used as lithium-ion batteries anode with superior lithium storage properties in terms of high initial capacity (1320 m Ah g−1 at 0.1 A g−1), good rate capability (425 m Ah g−1 at 2 A g−1), and excellent cycling stability (712 m Ah g−1 was retained over 300 cycles at 0.1 A g−1).

We demonstrate an efficient and compact ultraviolet laser at 303 nm generated by intracavity frequency doubling of a continuous wave (CW) laser diode-pumped Pr3+:YLiF4 laser at 607 nm. A cesium lithium borate (CLBO) crystal, cut for critical type I phase matching at room temperature, is used for second-harmonic generation (SHG) of the fundamental laser. By using an InGaN laser diode array emitting at 444.3 nm with a maximum incident power of 10 W, as high as 68 mW of CW output power at 303 nm is achieved. The output power stability in 4 h is better than 2.85%. To the best of our knowledge, this is high efficient UV laser generated by frequency doubling of an InGaN laser diode array pumped Pr3+:YLiF4 laser.

Rare-earth ions doped fiber lasers at 2 µm can supply various applications in daily life. In this paper, Ho3+/Yb3+ co-doped tellurite glasses were prepared by the high temperature melting method to obtain a strong 2 µm mid-infrared fluorescence emission. The characterization results of the X-ray diffraction (XRD) and differential scanning calorimeter (DSC) show that this glass possesses good crystallization resistance and thermal stability, and its ΔT is 136 °C, which can be successfully drawn. Under the 980 nm LD excitation, strong green (550 nm) and red (660 nm) up-conversion emission were obtained, meanwhile, intensive 2 µm mid-infrared emission was also achieved, and the emission intensity was significantly improved with the increase of Yb3+ concentration, when the Yb3+ content was 2.0, the 2 µm mid-infrared emission intensity was increased by about 28% compared with the content of 0.5, it should be noted that the concentration of Yb3+ is required to be strictly controlled to prevent concentration quenching. In addition, the luminescence process of Ho3+ was further elaborated through the energy transfer mechanism. All results indicate that the Ho3+/Yb3+ co-doped tellurite glass can be an attractive candidate for up-conversion and mid-infrared fiber laser materials.

In this paper, Ho3+, Yb3+ and metal Ag nanoparticles (NPs) tri-doped tellurite glass were synthesized by melt quenching. Combining X-ray diffraction, Raman spectroscopy, and Differential thermal analysis tests, multiple structural units were found in the synthetic glass samples which provided the possibility to achieve high concentration and uniform doping of rare earth ions without degrading the glass forming ability and thermal stability. The fluorescence emission of glasses at 2 μm, 3.9 μm, and 4.1 μm were focused on, as a consequence, the Ho3+/Yb3+/AgNPs tri-doped tellurite glass achieved strong emission at 2 μm, 3.9 μm and 4.1 μm, and the full width at half maximum (FWHM) at 4.1 μm is 316 nm under the 980 nm LD excitation, which realized broadband fluorescence emission. In addition, the fluorescence lifetimes of the glass at 2 μm, 3.9 μm and 4.1 μm are 4.79 ms, 3.81 ms and 4.28 ms meaning the lower laser oscillation threshold the glass holds. It is particularly noteworthy that the emission intensity had been greatly improved about 30% at 2 μm and 27% at 3.9 μm and 4.1 μm with the introduction of AgCl into the matrix, respectively, which was mainly effected by local surface plasmon resonance (LSPR) of AgNPs and the energy transfer between Ag species and Ho3+, whereas the content of AgCl must be strictly controlled to prevent the concentration quenching to decrease the emission intensity. The obtained results demonstrate that Ho3+/Yb3+/AgNPs tri-doped tellurite glass possesses an ideal application prospect on mid-infrared fiber and laser materials.

Uniform and highly oriented NiSi0.8Ge0.2 layer is achieved by using a Ti interlayer during Ni germanosilicidation. Compared with the reference sample, the morphology of the grown Ni(Si0.8Ge0.2) layer with a Ti interlayer is improved with a better uniformity and smoother surface and interface. The Ni(Si0.8Ge0.2) layer is highly oriented grown on Si0.8Ge0.2 substrate at 500 °C annealing in the case of 5 nm Ti interlayer, with the preferred orientation relationships of (010) Ni(Si0.8Ge0.2) || (001) Si0.8Ge0.2 and (101) Ni(Si0.8Ge0.2) || (110) Si0.8Ge0.2. In addition, most of Ti atoms from the original interlayer diffuses toward the surface after annealing. The reduced Ni diffusion is conducive for the uniform reaction between Ni and Si0.8Ge0.2, resulting in highly oriented Ni(Si0.8Ge0.2) grown on Si0.8Ge0.2.

Nd3+-Er3+-Pr3+ tri-doped tellurite glasses with lower phonon energy (768 cm−1) were prepared by conventional melt-quenching method. Under the excitation of 488nm, an ultra-broadband emission from 760 to 1150 nm with full-width at half-maximum (FWHM) of about 262 nm was observed in the prepared Nd3+-Er3+-Pr3+ tri-doped glass sample, larger than that of the recently reported glasses. The DSC curve shows that the prepared tellurite glass has high glass transition temperature (Tg=382°C) and good thermal stability (ΔT=203°C). The gain coefficient, maximum absorption and emission cross section of Nd3+-Er3+-Pr3+ tri-doped tellurite glass for Nd3+:4F3/2→4I9/2 and Er3+:4I11/2→4I15/2 transitions are calculated as 0.41 cm−1, 0.80 × 10−20 cm2, 1.07 × 10−20 cm2, 0.35 cm−1, 0.37 × 10−20 cm2 and 0.45 × 10−20 cm2, respectively. Compared with the recently reported glasses, these values were effectively improved. This means that the prepared tellurite glass has better fluorescence emission and laser gain performance.

Nd3+-Er3+-Pr3+ tri-doped tellurite glasses with lower phonon energy (766 cm−1) were prepared by conventional melt-quenching method. Under the excitation of 488 nm, an ultra-broadband emission from 1250 to 1650 nm with full-width at half-maximum (FWHM) of about 332 nm was found in Nd3+-Er3+-Pr3+ tri-doped tellurite glass, larger than that of recently reported tellurite glasses. The DSC curve showed that the prepared glass had a high glass transition temperature (Tg = 381 °C) and good crystallization resistance (ΔT = 195 °C). Raman spectra and XRD pattern revealed the information of different vibrational units and the amorphous structure of the prepared glass. The maximum absorption cross-section, emission cross-section and gain coefficient of the prepared tellurite glass were calculated as 1.05 × 10−20 cm2, 1.34 × 10−20 cm2 and 1.55 cm−1, respectively. Compared with the recently reported glasses, these values were improved. This indicates that better laser gain and fluorescence emission could be obtained in the prepared tellurite glass. The results showed that Nd3+-Er3+-Pr3+ tri-doped tellurite glass is a promising near-infrared optical material.

The enhancement of mid-infrared (MIR) fluorescence emission (1800–3000 nm) was achieved by adding Li+ ions into Er3+/Ho3+ co-doped oxyfluoride silicate glass-ceramics containing YF3 nanocrystals, which was prepared by conventional melt-quenching. The introduction of Li+ ion destroys the glass network [Si–O–Al] structure, and affects the crystallization ability of the substrate glass. In addition, the crystal field effect significantly enhances the up-conversion and MIR fluorescence emission of the prepared samples, with a decay time of 4.6 ms and the maximal absorption cross section (σabs) of 1.43 × 10−20 cm−2 at 1950 nm, as well as emission cross section (σem) of 1.73 × 10−20 cm−2 at 2021 nm. The results indicate that the prepared samples have excellent fluorescence properties and can be used for MIR lasers.

The antimicrobial efficacy of silver nanoparticles (Ag NPs) modified material was generally governed by the dose of the particles or their capability to release silver ions. Here, it was found that Ag NPs acted against microbes by cooperating with tantalum oxide (TAO) in a Schottky barrier dependent manner. Size tunable Ag NPs were in situ fabricated and immobilized on TAO coating by a silver plasma immersion ion implantation process (Ag PIII). The antibacterial efficacy of these Ag NPs was reversely dependent on their size, that is large particles (~20 nm) were more efficiency than small ones (~10 nm) in defeating the invasion by bacteria. The result is consistent with the prediction of Schottky-Mott theory, which rectified the electron transfer nature across the interfaces between Ag NPs and the TAO substrate.

A novel photothermoelectric resistance effect of the Ti/SiO2/Si films induced by 10.6 [Formula: see text]m CO2 laser is discovered and investigated. The transient response of the resistance is observed and analyzed in this work. Under the continuous irradiation of the laser, the thermal resistance value changes with the irradiating time and gradually reaches a stable saturation. The results indicate that the rise time of thermal resistance is shortened and its change rate increased as laser power gets higher. The inner battery of the ohmmeter exerts the positive or negative bias voltage, causing the diffusion motion direction of the hot electrons to be opposite or the same direction with the drift motion, which can increase or decrease the thermal resistance value. Those experimental phenomena are explained by the drift and diffusion motion of the electrons. Based on the results, the Ti/SiO2/Si structure is an attractive candidate for thermal effect devices.

We investigate transmission and reflection properties of a broadband pulse with normal incidence on silicon-metal-silicon (SMS) for the first time, to the best of our knowledge. The results show that in lower frequency range, the transmission is close to zero, and the reflection and loss are in the range 0.50–0.90, 0.10 to 0.50, respectively. In higher frequency range, the transmission spectrum has two peaks, with transmittance 0.69, 0.90, and at same frequencies as the transmission peaks, the reflection spectrum has two troughs with reflectance 0.00, 0.02 and corresponding losses are 0.10, 0.29, respectively. This simple waveguide structure may have potential applications in silicon photonics, such as filters and laser oscillation cavities.

Ho3+/Yb3+ co-doped tellurite-germanate glasses with lower phonon energy (779 cm−1) and higher thermal stability were prepared by conventional melt quenching. The mid-infrared fluorescence spectra of the prepared glasses were investigated by 980 nm laser pumping. The full width at half maximum (FWHM) and lifetime of the sample at 2.0 μm were 186 nm and 8.09 ms, respectively. Compared with the reported glasses for this type, these values were effectively improved. In particular, the FWHM and emission lifetime of the prepared glass at 4.1 μm reached 276 nm and 8.17 ms, respectively, which have not been reported yet. Meanwhile, compared to the recently reported tellurite glasses, the ΔT was increased by approximate 22.7%. Strong up-conversion visible emission peaks at 547, 662, and 756 nm and near-infrared emission at 1.20 μm were observed in Ho3+/Yb3+ co-doped glass. Meanwhile, photoluminescence measurements showed that the doping of the appropriate amount of Yb3+ ions significantly enhanced the emission intensity of the samples at 2.0 μm and 4.1 μm. Therefore, the Ho3+/Yb3+ co-doped tellurite-germanate glass is a promising candidate for mid-infrared fiber and laser materials applications.

We demonstrate an effective way to improve the thermal stability of nickel stanogermanide (NiGeSn) by incorporating platinum (Pt) interlayer. After Ni/Pt/GeSn samples reacted at different temperatures (300°C–500°C), we obtained uniform NiGeSn films. By means of sheet resistance measurement, scanning electron microscopy, cross-sectional transmission electron microscopy and energy dispersive X-ray spectroscopy characterization. These results show that in the existence of Pt, the applicable annealing temperature of NiGeSn is broadened and the morphology of the NiGeSn film is smoother and more uniform.

Graphical abstractDisplay Omitted The interfacial reactions of Ni/Ti bilayers on relaxed Si0.7Ge0.3 substrates were investigated.The incorporation of Ti exhibited significant beneficial effects on improving the thermal stability of NiSiGe layers.The incorporation of Ti greatly improves the surface and interface roughnesses of NiSiGe layers.The mechanism of Ti induced NiSiGe/SiGe contacts enhancement is also analyzed. We investigate the effects of a Titanium (Ti) interlayer on the formation of nickel-germanosilicide on relaxed Si0.7Ge0.3 layers. The layer morphology and sheet resistance are investigated at different annealing temperature. The presence of Ti atoms increases the thermal stability of NiSiGe about 100?C. We demonstrate that the Ti atoms retard the Ni germanosilicidation rate, stabilize the NiSiGe phase, and smooth the NiSiGe/SiGe interface.

We study the formation of nickel-germanosilicide (NiSiGe) on Sn ion pre-implanted Si0.8Ge0.2 layers. The Sn influences on NiSiGe morphology and sheet resistance are investigated at different annealing temperature. The NiSiGe films were characterized by scanning electron microscopy (SEM), Rutherford backscattering spectrometry (RBS), cross-section transmission electron microscopy (XTEM), and Energy Dispersive X-ray spectrometer (EDX) techniques. It is shown that the presence of Sn atoms increases the thermal stability of NiSiGe about 150 °C. We demonstrate that the Sn atoms retard the Ni germanosilicidation rate, stabilize the NiSiGe phase, and smooth the NiSiGe/SiGe interface.

A laser diode side pump all-solid-state pulse laser at 589 nm with high power and high conversion efficiency and small volume is demonstrated by intracavity sum frequency generation. By optimizing the cavity and adopting etalon techniques, a quasi continuous wave at 589 nm laser source, which has a maximum output power of 11.4 W, a repetition rate of 5 kHz, and a pulse width of 135 ns, is developed. The optical to optical conversion efficiency is up to 6.5% and the power stability is better than 2% in 8 hours.

We design an in-plan hetero-photonic crystal (IP-HPC) structure which can dynamically control the quality (Q) factor of the nanocavity by using Kerr effect. In both theoretical derivation and numerical simulation, the Q factor could be dynamically turned with a larger scale than reported before. We study the effect of distance between the cavity and the hetero-photonic crystal on the Q factor. With optimal parameters, the Q factor of the nanocavity can be changed from ∼130,000 to ∼880,000 in the IP-HPC system.

Output nonlocality and nonclassicality for the two modes are investigated in an entanglement laser system. Within the framework of a quantum theory of multiwave mixing, nonlocality and nonclassicality are discussed according to the violations of Bell inequality and Cauchy-Schwarz inequality. It is found that both nonlocality and nonclassicality can be fulfilled in the outside cavity fields under certain conditions. It is also shown that there are some nonclassical states that do not show nonlocality.

The generation and evolution of entanglement and squeezing for the two-mode fields are discussed in a cascade three-level atomic system. Two photons of a strong external pump field induce atomic coherence between the top and bottom levels. The dynamics of this system in the presence of cavity losses is studied. It is shown that entanglement and squeezing between the two modes increase initially, then decrease and eventually disappear. The periods of them are extended with the increasing of the pump field intensity. The effects of the cavity losses on squeezing and entanglement are also discussed.

We study the statistical properties of thermal radiation in a Kerr nonlinear blackbody in which bare photons with opposite wave vectors and helities are bound into pairs and unpaired photons are transformed into a different kind of quasiparticle, the nonpolariton. This paper investigates the statistical properties of the photon blackbody field by using the second-order correlation function, the phase space distribution function, the photon number distribution and the nonclassical depth. The numerical computation and a discussion of the results are present.

The dynamics of entanglement for two-mode magnons in an antiferromagnet is investigated according to the entanglement criterion proposed by Duan et al. [L.M. Duan, G. Giedke, J.I. Cirac, P. Zoller, Phys. Rev. Lett. 84 (2000) 2722]. It is shown that entanglement between the two modes of magnons can be generated and occurs periodically with time.

We investigate entanglement of a two-mode three-level atomic system in a doubly resonant cavity in the steady state. We show that the system reaches a entangled state even in the presence of cavity losses. Moreover, violation of Bell's inequality of the entangled state is also discussed.

In this Letter, some properties of magnetopolarons in two-dimensional quantum dot are investigated by two-mode squeezed states transformation. This method considers linear functions, bilinear functions of the phonon operators and the correlation between two longitudinal optical (LO) phonon modes, which is based on the Lee–Low–Pines and Huybrechts (LLP–H) canonical transformations. So it can provide results not only for the ground state energy but also for the excited states energies, furthermore, it can be applied to the entire range of the electron–phonon coupling strength. Using two-mode squeezed states transformation, we have obtained more accurate results for the ground state energy, excited states energies and renormalized cyclotron masses for some possible transitions.

In this Letter we discuss squeezing state of magnon in ferromagnet, which permits a reduction in the quantum fluctuation of the spin component to below the zero-point quantum noise level of coherent magnon states. We investigate the generation of squeezed magnon state through calculating the expectation values of spin component fluctuation. The mean field theory is introduced in dealing with the nonlinear interaction terms of Hamiltonian of magnon system.

The effect of an ultrathin titanium (Ti) interlayer on the formation of nickel germanosilicide on strained Si 0.8 Ge 0.2 /Si(100) was studied. A uniform flattened Ni(Si 0.8 Ge 0.2 ) layer is finally formed after rapid thermal annealing. The transition temperature from the Ni-rich germanosilicide phase to the monogermanosilicide phase increases for the incorporation of Ti. The Ti interlayer acting as an inter-diffusion barrier layer well balance the silicidation velocity, which contributes to the achievement of the highly-oriented nickel germanosilicidation. The strain of Si 0.8 Ge 0.2 remains nearly the same after the RTA procedure. Considering the smooth interface between the NiSiGe layer and the SiGe substrate, the approach presented indicates a potential application for S/D contacts in the future CMOS devices.

By coating with a carbon film and graphene sheet (GS) on position-sensitive detectors based on the metal–oxide–semiconductor structure, sensitivity, linearity, and saturation power are significantly improved. We attribute this enhancement of absorptivity to lasers. The improvement effect of carbon film is more obvious than that of GS coating because of GS’s high conductivity.

The continuous-variable (CV) entanglement of the output fields is investigated in a four-level correlated emission laser system. The atomic coherence is introduced using two external classical driving fields. Based on the input–output theory, it is shown that the output entanglement and the entangled photons of the system can be achievable under certain conditions. Moreover, it is found that the two-mode entanglement has a close relation with the intensities of two external driving fields.