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The solid‐state nuclear optical clock based on 229Th‐doped crystal has great advantages in frequency stability, excitation and detection of nuclear transition, miniaturization, commercialization, and spaceborne ability of nuclear optical clock. Here, the potential of LiF crystal as a host for Th ions is predicted by theoretical calculation, and on this basis, the Th:LiF crystal is successfully grown experimentally for the first time. The theoretical results demonstrate that although the challenges of charge nonconservation and ion radius mismatch between Li+ and Th4+ ions exist, effective doping of thorium can still be achieved via energetically favorable charge compensation mechanisms in an F‐rich environment, and the transmittance of Th:LiF crystal in nuclear transition band will only have a slight decrease, smaller than that of pure LiF crystal. The experimental results prove that the doping concentration of Th:LiF crystal can reach about 8.3 × 1018 cm−3 and the transmittances of 1 mm thick Th:LiF and pure LiF crystal samples grown in similar conditions are ≈68% and 72% at 152.7 nm, respectively. The Th:LiF crystal with high doping concentration, high transmittance, and low background luminescence is expected to be a promising candidate for solid‐state nuclear optical clock materials. [ABSTRACT FROM AUTHOR]

CeSb2 is a homologue of rare-earth diantimonides. This work reports a systematic study of a series of high-quality single crystals of CeSb2 grown by a self-flux method, which is a heavy fermion Kondo metal with intricate magnetic transitions. We have grown four types of crystals with different initial material ratios in order to investigate the effect of growth conditions on the quality of the as-grown crystals. The phase purity, morphology and composition of the synthesized samples were studied with X-ray diffraction, scanning electron microscopy, electron-probe microanalysis, and Raman-scattering spectroscopy to evaluate their quality. It is found that an inappropriate raw material ratio will lead to the inhomogeneity and poor crystallinity of the as-grown crystal. In addition, the electrical transport properties of the as-grown crystals were measured, from which the residual resistivity ratios were extracted to further examine the homogeneity and crystalline quality. Furthermore, the magnetoresistance properties of CeSb2 were observed. Through a systematic study on CeSb2, the most suitable starting ratio for the growth of CeSb2 was obtained, which might serve as a guide for the growth of other light rare-earth diantimonides. [ABSTRACT FROM AUTHOR]

Vertically aligned ZnO nanowire arrays were grown on ZnO single crystals using a chemical vapor deposition method. Nucleation sites were defined by patterning Au nanodot catalysts fabricated through anodized aluminum oxide (AAO) templates. Morphology and structure characterizations showed that the as-grown nanowires had the single-crystal hexagonal wurtzite structure with a <0001> growth direction. By changing the pore distance of AAO, the density of nanowires could be well controlled. A sharp peak in the UV region and a weak broad peak in the visible region were shown in the room temperature photoluminescence spectra, suggesting the high-quality ZnO nanowire arrays were obtained. [ABSTRACT FROM AUTHOR]

Up to now, it is still challenging to solve the thermal management problem of the solid-state laser. Herein, a new thermal management method is conducted, which is direct deposited diamond films on laser crystals. By microwave plasma chemical vapor deposition (MPCVD) method, we have successfully synthesized high-quality diamond films on Y 3 Al 5 O 12 (YAG) substrates to improve the thermal performance of YAG crystals. Diamond films were grown with different pre-treatments and deposition parameters, where the pre-treatment method is to expose the substrate to diamond growth conditions before the seeding step. After deposition, the quality, thermal properties, and optical properties of as-grown samples were investigated in detail to study the impact of the pre-treatment and deposition parameters on the properties of the film. The results revealed that a sufficient pre-treatment process is necessary for the deposition of continuous diamond films on YAG substrates, while a relatively high temperature and low methane concentration during the deposition process are conducive to obtaining high-quality diamond films. Furthermore, it was found that depositing diamond films on YAG crystals can effectively improve the thermal conductivity of the materials with slightly affecting their optical properties, which provides a new choice for the thermal management of the solid-state laser. [Display omitted] • Continuous diamond films were deposited on YAG substrates by MPCVD method. • Effects of deposition conditions on the quality of diamond films were studied. • The deposition of diamonds effectively improved the thermal performance of YAG. • The deposition process had little effect on the optical properties of YAG. [ABSTRACT FROM AUTHOR]

• The neodymium-doped CeF 3 single crystal without crack was grown by the Bridgman Stockbarger method. • The magneto-optical performances of Nd:CeF 3 were investigated. • The laser induced damage threshold of Nd:CeF 3 was measured. The highly transparent neodymium-doped CeF 3 (Nd:CeF 3) single crystal with diameter of 20 mm × 35 mm was grown by the Bridgman Stockbarger (BS) method. The optical and magneto-optical (MO) performances of Nd:CeF 3 were experimentally investigated in UV–Vis and near-IR spectral range. Notably, Nd:CeF 3 exhibits high transparency and significantly enhanced Faraday rotation. Compared with commercial terbium gallium garnet (TGG), Nd:CeF 3 has higher Verdet constants at different measured wavelengths. The bulk laser-induced damage of c -cut Nd:CeF 3 crystal was also determined by R-on-1 method. All the results demonstrate that the properties of Nd:CeF 3 are superior to those of CeF 3 and TGG. The excellent MO properties of Nd:CeF 3 with a used wavelength of 0.3–2.2 µm are especially important for high power isolators in order to cover UV–Vis and the entire near-IR range. [ABSTRACT FROM AUTHOR]

A novel transparent Pr 3 + , Ce 3 + co-doped terbium gallium garnet (Pr,Ce:Tb 3 Ga 5 O 12 , Pr,Ce:TGG) single crystal was grown by the Czochralski technique. Its transmittance is about 80% in 600 ∼ 1300 nm wavelength range except for special absorption peaks. The Verdet constants (V) of Pr,Ce:TGG crystal at 532 nm and 632.8 nm are − 230 and − 153 rad T−1 m−1, which are both larger than those of terbium gallium garnet (Tb 3 Ga 5 O 12 , TGG) crystal. The thermal conductivity of Pr,Ce:TGG crystal is 3.35 W m−1 K−1 at 300 K. Bulk laser induced damage threshold (LIDT) of Pr,Ce:TGG crystal was measured to be 15 J cm−2 by R-on-1 test. The results show that Pr,Ce:TGG crystal as magneto-optical material has potential ability to be used in optical isolators. • The Pr3+, Ce3+ co-doped terbium gallium garnet single crystal was grown by the Czochralski technique. • The growth and magneto-optical properties of Pr,Ce:TGG crystal were studied. • The thermal conductivity and bulk laser induced damage threshold of Pr,Ce:TGG crystal were measured. [ABSTRACT FROM AUTHOR]

The Dy,Pr:CeF 3 single crystal was successfully grown and its optical characteristics were investigated systematically. The analysis of energy transfer process between Dy3+ and Pr3+ in CeF 3 crystal was also carried out. The XRD study shows the crystal belongs to the hexagonal crystal system and its lattice parameters are a = 7.1252 Å and c = 7.2775 Å. The maximum phonon energy of the crystal was speculated to be 377.1 cm−1 by Raman spectrum. The absorption coefficient at 442 nm of Dy,Pr:CeF 3 crystal is 0.89 cm−1. The radiative lifetime of Dy:4F 9/2 level is 2.08 ms and the one of Pr:3P 0 level is 145.25 μs in Dy,Pr:CeF 3 crystal obtained by J-O theory calculation. The maximum emission cross-section of Dy: 4F 9/2 → 6H 13/2 transition is calculated to be ∼0.15 × 10−20 cm2 in the crystal. The fluorescence lifetimes of Dy:4F 9/2 , Pr:3P 0 and Pr:1D 2 levels are estimated to be ∼1.25 ms, ∼17.91 μs and ∼112.37 μs, respectively. The results show that Dy,Pr:CeF 3 crystal not only owns a larger absorption coefficient at 442 nm than Dy:CeF 3 crystal, but also holds the much longer lifetime of Pr:3P 0 level than Pr:CeF 3 crystal because of the energy transfer in Dy3+-Pr3+. • Dy, Pr co-doped CeF 3 crystal is successfully grown. • The optical characteristics of the Dy,Pr:CeF 3 crystal is investigated in detail. • The energy transfer process between Dy3+ and Pr3+ in CeF 3 crystal is also analyzed. • Lifetime of Pr:3P 0 level in Dy,Pr:CeF 3 is upgraded much longer than Pr:CeF 3. • Providing a reliable method to use Pr:3P 0 for laser output in Pr3+ doped crystal. [ABSTRACT FROM AUTHOR]

Single crystal of Nd3+ -doped SrB 4 O 7 (SBO) has been successfully grown by the Czochralski method. The spectroscopic properties were investigated and spectral parameters were calculated based on the Judd–Ofelt theory. The results suggest that the Nd:SBO crystal may have great potential as laser crystal, and through self-frequency doubling, it is expected to achieve the frequency conversion of the characteristic output of Nd3+ in the near infrared to obtain a visible laser. • Neodymium doped strontium tetraborate crystal was grown by Czochralski method for the first time. • Firstly, use it as a laser gain medium, a comprehensive spectral performance study and calculation have been carried out. • The spectral performance shows its potential as a laser gain medium. • Nd: SBO crystal is expected to realize the visible laser output by self-frequency doubling. [ABSTRACT FROM AUTHOR]

In this study, we report a successful Bridgman growth of Nd3+ and Er3+ co-doped CeF 3 (Nd,Er:CeF 3) single crystal with a size of Ø25 mm × 30 mm. The absorption and fluorescence characteristics of the Nd,Er:CeF 3 crystal were studied systematically. The results show that the fluorescence emission peaks were positioned at 547, 669, 1062.6, and 1542.6 nm, respectively. The fluorescence lifetimes centered at 1062.6 and 1542.6 nm for Nd3+ and Er3+ were 0.313 and 1.12 ms, respectively. Meanwhile, the spectroscopic properties of Nd,Er:CeF 3 crystals were investigated based on the Judd–Ofelt theory. Notably, the magneto-optical performance of the Nd,Er:CeF 3 crystal was investigated for the first time. The Verdet constants of the Nd,Er:CeF 3 crystal at 532, 632.8, 1064, and 1310 nm are 220.3, 142.4, 40.7, and 23.1 rad T−1 m−1, respectively, which are significantly higher than those of undoped CeF 3 and traditional Tb 3 Ga 5 O 12. The results show that Nd,Er:CeF 3 is a bifunctional crystal with potential applications in laser and magneto-optical fields. • The Nd,Er:CeF 3 single crystal was grown by the vertical Bridgman method. • The spectroscopic and magneto-optical properties of Nd,Er:CeF 3 were investigated. • Novel Nd,Er:CeF 3 can be utilized in both lasers and magneto-optical devices. [ABSTRACT FROM AUTHOR]

Three Pr:PbF 2 single crystals with different doping concentrations (0.1, 0.5 and 1.0 at.%) have been detailed investigated to figure out the effect of doping concentration on spectroscopic properties for the first time. The XRD study shows the crystals belong to the cubic system and the lattice parameter of 1.0 at.% Pr:PbF 2 crystal is 5.9336 Å. The maximum phonon energy of three crystals was speculated as low as 259 cm−1 through Raman spectra. The absorption and fluorescence spectra of the Pr:PbF 2 crystals with different doping levels were recorded and analyzed with the J-O theory. The maximum absorption cross-section at 443 nm and maximum emission cross-section at 482 nm can be obtained as 1.00 × 10−20 cm2 and 1.08 × 10−20 cm2 in 1.0 at.% Pr:PbF 2 crystal, respectively. The gain cross-sections of the Pr:PbF 2 crystals become positive in a range of 482–497 nm once the population inversion level reaches 30 %. The maximum fluorescence lifetime of 3P 0 energy level was found as 33 μs in 0.1 at.% Pr:PbF 2 crystal. On the whole, the spectroscopic performance of Pr: PbF 2 crystal would be improved by increasing the Pr3+ doping level appropriately. • 0.1, 0.5 and 1.0 at.% Pr:PbF 2 crystals are successfully grown. • The effect of doping concentration on the spectroscopic properties of Pr:PbF 2 is discussed in detail for the first time. • 1.0 at.% Pr:PbF 2 crystal owns the larger absorption and emission cross-sections. • 1.0 at.% Pr:PbF 2 crystal also possesses a lower population inverse level for realizing positive gain. • Properly increasing doping concentration maybe an effective way to improve the spectral performance of Pr:PbF 2 crystal. [ABSTRACT FROM AUTHOR]

• The Nd,Ho:CeF 3 single crystal was grown by the vertical Bridgman method. • The spectroscopic and magneto-optical properties of Nd,Ho:CeF 3 were investigated. • Novel Nd,Ho:CeF 3 can be utilized in both lasers and photonic devices. In this study, a 1.5 at.% Nd3+ and 0.5 at.% Ho3+ co-doped CeF 3 (Nd,Ho:CeF 3) single crystal was successfully grown by the vertical Bridgman method. The absorption and fluorescence characteristics of the fabricated crystal were evaluated. The spectroscopic properties of the Nd,Ho:CeF 3 crystal were investigated based on the Judd–Ofelt (J–O) theory. The parameters Ω 2 , Ω 4 , and Ω 6 of Ho3+ were fitted as 0.338 × 10−20, 0.731 × 10−20, and 0.350 × 10−20 cm2, respectively. The fluorescence lifetimes centered at 1064 and 1970 nm for Nd3+ and Ho3+ were 261 and 47 μs, respectively. Notably, the magneto-optical performance of the Nd,Ho:CeF 3 crystal was investigated for the first time. The measured Verdet constants of Nd,Ho:CeF 3 at 532, 632.8, 1064, 1310, and 1550 nm were 228.0, 154.7, 42.4, 29.1, and 18.5 rad·T−1·m−1, respectively, which were significantly larger than those of pure CeF 3 and traditional Tb 3 Ga 5 O 12. The results demonstrated that Nd,Ho:CeF 3 crystals can be applied in both lasers and magneto-optical devices. [ABSTRACT FROM AUTHOR]

• A novel laser and magneto-optical Er:CeF 3 multifunctional crystal was successfully grown by the Bridgman method. • Er:CeF 3 crystal has excellent optical properties which supports its effectiveness as a 1.5 µm laser gain medium. • Er:CeF 3 crystal owns higher magneto-optical Verdet constants than those of pure CeF 3 and commercial Tb 3 Ga 5 O 12 crystals. In this study, a 2 at% erbium doped cerium trifluoride (Er:CeF 3) single crystal was grown using the Bridgman method. The consequent absorption, infrared transmittance, and fluorescence spectra were recorded. The spectroscopic properties of Er:CeF 3 crystals were intensively studied based on the Judd–Ofelt (J–O) theory. The Ω 2 , Ω 4 , and Ω 6 parameters were fitted to be 5.206 × 10−20, 1.805 × 10−20, and 3.06 × 10−20 cm2, respectively. The emission cross-section centered at 1564.6 nm was calculated to be 1.053 × 10−20 cm2, and the corresponding fluorescence lifetime was measured to be 1.675 ms. Additionally, the magneto-optical (MO) performance of the Er:CeF 3 crystal was investigated for the first time. The Verdet constants of Er:CeF 3 at 532, 632.8, 1064, and 1310 nm are 231.0, 165.4, 43.4, and 24.4 rad·T−1·m−1, respectively, which are significantly higher than those of pure CeF 3 and traditional Tb 3 Ga 5 O 12. The results show that the Er:CeF 3 crystal can be applied both to solid-state lasers and Faraday devices. [ABSTRACT FROM AUTHOR]

% Er: LuYO 3 crystal was grown by optical floating zone method for the first time. The absorption section at 980 nm is 0.35 × 10 − 20 cm2 with FWHM of 19 nm. The intensity parameters Ω i (i = 2,4,6) and the radiative transition probability, fluorescence branching ratio and lifetime of energy level transition from 4I 11/2 to 4I 13/2 and 4I 13/2 to 4I 15/2 of Er ion in Er: LuYO 3 crystal were calculated. The emission cross-sections centered at 2721 nm and 1556 nm are 1.46 × 10−20 cm2 and 2.61 × 10−21 cm2, which correspond to the transitions of Er3+: 4I 11/2 → 4I 13/2 and Er3+: 4I 13/2 → 4I 15/2 , respectively. The fluorescence lifetime of 4I 11/2 and 4I 13/2 under the excitation of 980 nm pulsed LD were 2.29 ms and 7.84 ms, respectively. The up-conversion fluorescence spectra and fluorescence decay curves were measured. The potential utility of the Er: LuYO 3 crystal as a tunable and ultra-short laser medium at 3.0 μm and 1.5 μm can be expected. 1. A novel Er:LuYO 3 single crystal was grown by the optical floating zone method; 2. The spectra of Er:LuYO 3 crystal exhibit wide-band properties and large emission cross-section at 3.0 μm; 3. The results proved that Er:LuYO 3 crystal can be a potential for the tunable lasers or ultra-short pulse generation at 3.0 μm. [ABSTRACT FROM AUTHOR]