Additional Hole Research Articles

Solvothermally silver doping boosting the thermoelectric performance of polycrystalline Bi2Te3

Bismuth telluride (Bi2Te3) is one of the most promising thermoelectric materials for commercial application at room temperature, but the thermoelectric performance of these materials still needs to be improved. In this study, we report a type of solvothermally Ag-doped Bi2Te3 microplate. By sintering these microplates into polycrystalline bulk materials, a high room-temperature figure of merit of 1 has been achieved. Based on comprehensive micro/nanostructural characterizations, we found that the solvothermally doped Ag in Bi2Te3 plays two main roles, namely as the dopants that effectively induce the point defects of AgBi and forming Ag2Te nanophases. AgBi can provide additional hole charge carriers, effectively adjusting the initially high electron carrier concentration in the system, while the Ag2Te nanophases effectively trigger energy filtering effect to maintain a high Seebeck coefficient, thereby contributing to a competitively high power factor of 25.5 μW cm−1 K−2 at 298 K. Simultaneously, a low thermal conductivity of 0.74 W m−1 K−1 is obtained due to the strong phonon scattering at various lattice imperfections, induced by the solvothermally Ag-doping, which include point defects, grain/phase boundaries, local lattice distortions, and dislocations. This work fills the gap in knowledge on the solvothermally Ag-doping mechanism in Bi2Te3 and provides guidance for the innovative design of high-performing inorganic thermoelectrics.

Exploring a Novel Technique to Tackle the Shortage of Devices for Hepatic Arterial Infusion Chemotherapy: Early Results of an Alternate Approach for Percutaneous Arterial Port Catheter Placement.

Dedicated catheters for hepatic arterial infusion chemotherapy were removed from the market. The purpose of this study was to assess the results of a novel approach to overcome the shortage of dedicated catheters for hepatic arterial infusion chemotherapy in the treatment of colorectal cancer liver metastases. We retrospectively included patients who underwent a percutaneous placement of a hepatic intra-arterial port catheter in a single tertiary center from February 2021 to June 2022. We examined the patient baseline characteristics, technical features of the modified procedures, technical success rates, complications and oncological outcomes. Fourteen patients (median age: 60 years; q1 = 54; q3 = 70; range: 53-81 years) underwent 15 modified procedures. The main modification of our placement technique consisted of the use of an indwelling 5-Fr Vertebral catheter, on the tip of which we created a two-sided additional lateral hole. The catheter was connected to a pediatric port. The primary success rate was 100%, and the secondary success rate was 93.3%. There were two late major complications, graded IIIa according to the Clavien-Dindo classification. The median liver progression free survival was 6.1 months (q1 = 2.5; q3 = 7.2; range: 1.3-11.6). Our experience suggests that the derived utilization of the devices used routinely in interventional radiology provides an effective solution that can compensate for the shortage of dedicated devices.

Selective reduction of NO3− to N2 using a highly stable Cu0/Cu2O-PANI-CNTs as a photocatalyst at neutral pH

The selective photoreduction of nitrate (NO3−) to nitrogen (N2) has emerged as an energy-efficient and environmentally friendly NO3− removal route under mild conditions. However, NO3− photoreduction often suffers low NO3− removal efficiency in the absence of hole scavengers at neutral pH, the generation of undesired side products (nitrite (NO2−), ammonium (NH4+), nitrogen oxides (NOx), etc.) and poor photocatalyst stability. In this study, a novel copper/copper(I) oxide-polyaniline-carbon nanotubes (Cu0/Cu2O-PANI-CNTs) photocatalyst was prepared through a combination of in situ polymerization and liquid phase reduction processes and used to reduce NO3− to N2. In the Cu0/Cu2O-PANI-CNTs/hv system, NO3− was reduced to NO2− by photogenerated electrons (ecb−) on the surface of Cu0/Cu2O, and the generated NO2− was further reduced to N2 by PANI, resulting in high N2 selectivity. –NH– in PANI acted as photogenerated hole (hvb+) capture centres, leading to NO3− photoreduction without additional hole scavengers. Given the interaction between Cu0, ecb− and PANI, Cu0/Cu2O-PANI-CNTs show excellent repeatability. A 100% NO3− removal efficiency and 100 % N2 selectivity could be achieved by the Cu0/Cu2O-PANI-CNTs/hv system at neutral pH. With river water, secondary effluent and the fourth reuse of the catalyst, the NO3− removal efficiencies were as high as 93.0%, 91.2% and 84.4%, respectively, with 100 % N2 selectivity.

Electrochemical control of surface passivation and deformation in InP nanotetrapods

In this study, we investigate the influence of electrochemical doping on the optical properties of single-crystalline InP nanotetrapods. Our focus is on examining the variations in photoluminescence (PL) intensity exhibited by these InP tetrapods in response to applied electrical potential. We observe that the PL intensity undergoes significant changes depending on the nature of the charge transfer occurring during electrochemical doping. Specifically, electron transfer from the electrode to the InP tetrapods leads to a noticeable quenching of the PL intensity, which can be attributed to the removal of surface ligands. However, when additional holes are injected, we observe a remarkable increase in the PL intensity exceeding 60%. Through an analysis of steady-state PL spectra and time-resolved PL decay dynamics, we propose that the injected holes occupy surface hole trap states, resulting in surface passivation and thus enhancing the PL intensity. Our findings highlight the potential of these InP nanotetrapods as a novel nanostructure for future advancements in nanocrystal applications. By elucidating the impact of electrochemical doping on the optical properties of these materials, we contribute to the understanding and exploration of their potential applications in optoelectronic devices and related fields.

Co-Evolution vs. Co-existence: The effect of accretion modelling on the evolution of black holes and host galaxies

ABSTRACT We append two additional black hole (BH) accretion models, namely viscous disc and gravitational torque-driven accretion, into the Numerical Investigation of a Hundred Astrophysical Objects (NIHAO) project of galaxy simulations. We show that these accretion models, characterized by a weaker dependence on the BH mass compared to the commonly used Bondi-Hoyle accretion, naturally create a common evolutionary track (co-existence) between the mass of the BH and the stellar mass of the galaxy, even without any direct coupling via feedback (FB). While FB is indeed required to control the final BH and stellar mass of the galaxies, our results suggest that FB might not be the leading driver of the cosmic co-evolution between these two quantities; in these models, co-evolution is simply determined by the shared central gas supply. Conversely, simulations using Bondi-Hoyle accretion show a two-step evolution, with an early growth of stellar mass followed by exponential growth of the central supermassive black hole (SMBH). Our results show that the modelling of BH accretion (sometimes overlooked) is an extremely important part of BH evolution and can improve our understanding of how scaling relations emerge and evolve, and whether SMBH and stellar mass co-exist or co-evolve through cosmic time.

Photo-induced oxygen vacancy formation and anomalous photoconductivity in solution-processed CoFe2O4 thin films

Designing an optoelectronic device requires adequate information about the photo-response of the active material. Here, we have studied the optical and optoelectrical properties of the solution-processed inverse spinel structured CoFe2O4 (CFO) thin film and correlated it with the photovoltaic performance of CFO active material-based all-oxide solar cell. The optical absorption spectra of spin-coated CFO films show the existence of a direct bandgap of 2.64 eV with a maximum absorption coefficient >105/cm. A simple spin-coated CFO/TiO2p–n heterojunction shows an open circuit voltage of over 0.95 V under 1 sun illumination. However, photo-induced oxygen vacancy formation and the desorption of surface oxygen lead to additional electron generation and hole capture, respectively, in the p-type CFO, resulting in an anomalous photocurrent decay under white light illumination, resulting in a low short-circuit current density. This study provides a fundamental understanding of photo-carrier dynamics in solution-processed CFO thin films and apprehends the photophysics of designing spinel-ferrite-based optoelectronic devices.

Transport layer engineering towards lower threshold for perovskite lasers.

Charge transport layers are essential for achieving electrically pumped perovskite lasers. However, their role in perovskite lasing is not fully understood. Here, we explore the role of charge transport layers on the lasing actions of perovskite films by investigating the amplified spontaneous emission (ASE) thresholds. We demonstrate a largely reduced ASE threshold and enhanced ASE intensity by introducing an additional hole transport layer poly(triaryl amine) (PTAA). We show that the key role of the PTAA layer is to accelerate the hot carrier cooling process by extracting holes in perovskites. With reduced hot holes, the Auger recombination loss is largely suppressed, resulting in decreased ASE threshold. Our argument is further supported by the fact that the ASE threshold can be further reduced from 25.7 to 7.2 μJ/cm2 upon switching the pumping wavelength from 400nm to 500nm to directly avoid excess hot hole generation. Our work for the first time exemplifies how to further reduce the ASE threshold with transport layer engineering through hot hole manipulation. This is critical to maintaining the excellent gain properties of perovskites when integrating them into electrical devices, paving the way for electrically pumped perovskite lasers. This article is protected by copyright. All rights reserved.

Confining Molecular Photosensitizer and Catalyst in MOF toward Artificial Photosynthesis: Validating Electron Transfer by In Situ DRIFT Study.

Exploration of different chemical systems for photocatalytic CO2 reduction by using sunlight en route to the achievement of artificial photosynthesis stems from global warming and the energy crisis. In this work, we have covalently grafted the molecular photosensitizer (PS) [Ru(MBA)(bpy)2]Cl2 (bpy: 2,2'-bipyridine) and the catalyst [Mn(MBA)(CO)3Br] inside the Zr-MOF-808 (Zr-MOF) nanopore postmodified with 2-(5'-methyl-[2,2'-bipyridine]-5-yl)acetic acid (H-MBA) and developed a single integrated system named Zr-MBA-Ru/Mn-MOF for the CO2 reduction reaction (CO2RR). Zr-MBA-Ru/Mn-MOF is found to be active toward CO2-to-CO conversion, with a maximum production of 1027 μmol g-1 after 26 h of reaction having >99% selectivity in the aqueous medium without any additional hole scavenger. The catalyst with direct sunlight in the aqueous medium is equally active for CO production, thus mimicking the natural photosynthetic process. We have performed an in situ diffuse reflectance Fourier transform infrared spectroscopy (FTIR) (DRIFT) study to unveil the electron transfer from the PS to the catalytic center during CO2 reduction by monitoring the changes in the carbonyl stretching frequency in the [Mn(MBA)(CO)3Br] center and correlated with the density functional theory (DFT) calculations. Additionally, we have performed in situ DRIFT spectroscopy to understand the reaction mechanism for the CO2-to-CO conversion.

발광층 호스트 구조에 따른 용액공정 기반 저분자 유기 발광 다이오드의 소자 거동

A method for achieving efficient and stable solution-processed small-molecule organic light-emitting diodes (OLEDs) is presented by utilizing a combination of a multifunctional hole injection layer (HIL) and a mixed-host emitting layer (EML). The polymeric HIL facilitates efficient hole injection into the solution-processed EML and blocks electrons from the EML through self-organization of polymer chains in the HIL. In addition to the multifunctional HIL, the optimized mixed-host EML, composed of electron and hole transporting host materials, along with phosphorescent dopant, enables efficient energy transfer, balanced charge transport, and efficient charge carrier recombination in the device. As a result, it improves luminance (~14,000 cd/m2), luminous efficiency (~55 cd/A), and operational lifetime (~180 minutes under constant current emitting initial luminance of 1,000 cd/m2, equivalent to approximately 150 hours at an initial luminance of 100 cd/m2). Notably, this device architecture does not include an additional hole transporting/electron blocking layer. This is because the introduction of a mixed-host composition widens the recombination zone in the EML, effectively preventing triplet-triplet excitons/triplet-polaron annihilation caused by charge carriers and excitons accumulated at the narrow heterointerfaces in OLEDs.

Ferromagnetic coupling mechanism and vacancy defect regulation strategy of V-doped LiMgAs

First-principles calculations were conducted to investigate the electronic structure and magnetic coupling mechanism of V-doped LiMgAs. The regulation strategy of Li vacancy defects on magnetism was also adopted. The results showed that all the designed defective configurations exhibited thermodynamic stability evaluated from the formation energy. The V nearest neighbor doping configuration occupied the lowest formation energy of −9.26eV and performed the strongest stability. V dopant had advantages in magnetic introduction and the maximum atomic magnetic moment in this study was 6.40 μB/V. The ground state of the magnetic coupling was determined by the energy difference of the doping configurations for magnetic ions antiferromagnetic and ferromagnetic arrangements. The magnetic dopants existed in Li(MgV)As system by ferromagnetic coupling and the ferromagnetic stability weakened with the increase of the V atom separation. The incorporation of Li vacancy defect promoted the enhancement of ferromagnetism. The optimal design configuration was V atoms nearest neighbor doping with one Li vacancy defect with the energy difference of 0.27eV, which performed the strongest ferromagnetic stability. The removal of Li ion introduced the additional itinerant hole carrier and elevated the non-localized characteristics of the carriers in p-d hybrid orbitals, which facilitated the electron exchange between magnetic ions. In this paper, a novel type of dilute magnetic semiconductor with controllable carriers was designed and the mechanism of ferromagnetic coupling was revealed, which provided a theoretical reference for the subsequent studies.

Unique topological classification of complex reentrant atrial tachycardias enables optimal ablation strategy

Abstract Funding Acknowledgements: Type of funding sources: Public grant(s) – EU funding. Main funding source(s): ERC starting grant - SMARTHEART (Nele Vandersickel) B Reentry is a common underlying mechanism of atrial tachycardia (AT). Reentry loops form around anatomical or functional 'holes' in the electrophysiological substrate and dominate the atrial cycle. Terminating a 'full' loop may cause previously 'suppressed' loops around another hole to become dominant. Interpretation of electroanatomical maps can thus be tedious: a full loop may be easily identified, but predicting suppressed loops is complex. We propose that topological classification may aid identification of suppressed loops in complex AT and improve ablation procedures. O Given a map of reentrant clinical AT, we aim to unambiguously classify the AT and suggest an operator-independent optimal ablation strategy. M The left atrium can be described topologically as a closed surface with three ‘holes’: mitral valve, left and right pulmonary veins (similar for the right atrium). Non-conductive tissue may constitute additional topological holes in the substrate. Anatomical reentry can occur around any of the holes described above. Therefore, we uniquely categorize an AT by identifying the number of holes in combination with the presence of full and suppressed loops. Fig. 1-2 shows the finite number of possible combinations for 3 and 4 holes. An optimal ablation strategy should terminate both full and suppressed loops, by connecting their corresponding holes. Directed graph mapping (DGM) is a method and software implementation to analyze arrhythmia by constructing a directed network from local activation time maps. We extended DGM to perform topological classification of AT. We hypothesize that the full reentry loops will correspond to the cycles detected by DGM in the network, while suppressed loops are characterized by activity propagating around a hole for at least 60% of its circumference. To test our algorithms, we generated > 1000 simulations corresponding to 5 different scenarios of Fig. 1-2 whereby the circumference of the suppressed loop was varied between 50% and 90% by adding slow conductive tissue. We also classified 110 clinical cases of mapped AT retrospectively and compared our suggested ablation strategy with the clinical ablation lines which ended the AT. R Terminating solely the full loops by an ablation line led to the suppressed loops creating a slower AT in 95% of simulations. Further ablation to terminate the suppressed loop ended the AT. Following our suggested ablation strategy directly terminated the AT. The ablation strategy suggested by DGM was topologically equivalent to clinically successful ablations in 90% of clinical cases. In 5 cases, DGM correctly predicted that the chosen ablation lead to a suppressed loop becoming dominant, resulting in slower AT. C We presented a unique topological classification of AT. We showed that suppressed loops play a pivotal role as not ablating them leads to slower AT. Benefits include preventing redo maps, shorter and operator independent procedures, and possibly reducing AT recurrence.

CdS@Ni3S2/Cu2S electrode for electrocatalysis and boosted photo-assisted electrocatalysis hydrogen production

Photo-assisted electrocatalysis (PA-EC) water splitting technology, which combines photocatalysis and electrocatalysis, has gradually become a research hotspot in the production of green hydrogen energy. Herein, for the first time, novel Cu/Ni alloy foam self-supporting CdS@Ni3S2/Cu2S core–shell nanorod arrays are prepared by a simple one-pot hydrothermal process. The CdS@Ni3S2/Cu2S exhibits both excellent electrocatalytic and photo-assisted electrocatalytic water splitting performance. During the long-time PA-EC water splitting test, the average H2 production rate reaches 568.1 μmol cm-2h−1, which is about 1.8 times higher than that of 284.1 μmol cm-2h−1 under dark condition. In addition, the electrical-to-hydrogen (ηETH) and solar-to-hydrogen (ηSTH) conversion efficiency reaches to be 97% and 8.9%, respectively. Mechanism investigation results show that during EC water splitting process, CdS nanorods mainly play as support material for the electroactive Ni3S2 and Cu2S. While, in the PA-EC process, CdS, Cu2S and Ni3S2 were photoexcited by light irradiation, and just as the presence of additional photogenerated electrons and holes, CdS@Ni3S2/Cu2S exhibits boosted photo-assisted water splitting properties. This work provides a new strategy for the construction of bifunctional photocatalysts combined with electrocatalysts in photo-assisted electrocatalysis overall water splitting.

Analisis Reject Produk Sayap Pesawat Terbang Komponen Ref D-Nose Panel Menggunakan Metode Statistical Quality Control (SQC) di PT XYZ

The manufacture of aircraft wings is a complex production process that requires high accuracy and precision. Each component must be manufactured to strict standards in order to meet the expected safety and quality criteria. One of the problems that often arise in the production process is component reject, where the component does not meet the set quality standards and must be discarded. The Ref D-Nose Panel component is a very important part in the manufacture of aircraft wings. This section serves as a protector and stabilizer on the nose of the aircraft wing. Therefore, the quality and accuracy of the manufacture and installation of these components is very important to ensure the safety and quality of the aircraft. During the manufacture of Ref D-Nose components, it was possible for these components to become damaged. Defects in the D-nose plate components can affect the quality and performance of the aircraft and even endanger the safety of passengers. The Importance of Reject Analysis for the Aviation Industry, which is included in a high-risk industry, is one of the things that is very influential for the quality of a product, so that there is no loss that must be compensated by the PT for consumers due to the occurrence of rejects. This loss is because the cost of making a component is very large and if the component is not in accordance with the wishes of the consumer, the consumer does not want to accept the component so that the loss is borne by the company. The research was conducted only by using Pareto Charts. The application of the Pareto Diagram is expected to be able to reduce the defect rate so that the quality of the company can increase. , eight types of defects were identified in the Ref D-Nose Panel component consisting of pitting corrosion defects on the surface area, corrosion toolmarks, scratches on marking areas, corrosion toolmarks, damagers, damaged parts/materials, diameter damage, False Cut errors in the chemical mill area , additional hole diameter on the countersunk area, and Actual contour part.

Effects of Secondary Current on the Local Erosion Induced by Circular Turbulent Wall Jets in Cross Flow

This paper presents the results of a series of laboratory experiments, by placing a turbulent wall jet in the upstream and downstream of a 90° channel bend, to investigate the effects of secondary flow on formation of local sediment erosion and deposition. The effects of jet and current flow intensities on the erosion pattern were characterized by the jet’s Reynolds number, Re, channel Froude number, Fr, and the ratio of water depth to nozzle diameter, h/do. The geometrical characteristics of local erosion such as jet trajectory, maximum scour depth, ds, and maximum mound height, hm, were measured. The area and volume of scours and mounds were calculated from measurements, and the results were correlated with the controlling parameters. Experimental observations indicated the existence of distinct scour patterns due to variations of channel Froude number. Two additional scour holes were identified due to the effect of stream interactions and formation of vortex regions immediately downstream of sediment mound. It was found that both channel and jet flows contributed to trajectory of the jet and the footprint of erosion. A threshold Froude number of Fr=0.091 was identified at which the current and jet flow were in equilibrium. The results showed that for a constant value of Fr, all scour parameters increased with increasing Reynolds number. However, Re did not have any effects on the jet’s deflection. Comparing the erosion profiles in the upstream and downstream bend indicated that the secondary current and turbulent redistribution altered the erosion and mound formation in the downstream of the bend in relatively high Reynolds (i.e., Re≥23,000), high channel Froude numbers (i.e., Fr>0.091) and high jet submergence (i.e., h/do>10.53).

Di(arylcarbazole) Substituted Oxetanes as Efficient Hole Transporting Materials with High Thermal and Morphological Stability for OLEDs

A group of di(arylcarbazole)-substituted oxetanes has been prepared in Suzuki reactions by using the key starting material 3,3-di[3-iodocarbazol-9-yl]methyloxetane and various boronic acids (fluorophenylboronic acid, phenylboronic acid or naphthalene-1-boronic acid). Full characterization of their structure has been presented. The low molar mass compounds represent materials having high thermal stability with 5% mass loss thermal degradation temperatures in the range of 371-391 °C. Glass transition temperatures of the materials are also very high and range from 107 °C to 142 °C, which is a big advantage for formation of stable amorphous layers for optoelectronic devices, i.e., organic light emitting diodes. Hole transporting properties of the prepared materials were confirmed in formed organic light emitting diodes with tris(quinolin-8-olato)aluminium (Alq3) as a green emitter, which also served as an electron transporting layer. In the device's materials, 3,3-di[3-phenylcarbazol-9-yl]methyloxetane (5) and 3,3-di[3-(1-naphthyl)carbazol-9-yl]methyloxetane (6) demonstrated superior hole transporting properties than that of material 3,3-di[3-(4-flourophenyl)carbazol-9-yl]methyloxetane (4) based device. When material 5 was used in the device structure, the OLED demonstrated rather low turn-on voltage of 3.7 V, luminous efficiency of 4.2 cd/A, power efficiency of 2.6 lm/W and maximal brightness exceeding 11670 cd/m2. HTL of 6 based device also showed exclusive OLED characteristics. The device was characterized by turn-on voltage of 3.4 V, maximum brightness of 13193 cd/m2, luminous efficiency of 3.8 cd/A and power efficiency of 2.6 lm/W. An additional hole injecting-transporting layer (HI-TL) of PEDOT considerably improved functions of the device with HTL of compound 4. The modified OLED with a layer of the derivative 4 demonstrated exclusive characteristics with turn-on voltage of 3.9 V, high luminous efficiency of 4.7 cd/A, power efficiency of 2.6 lm/W and maximal brightness exceeding 21,000 cd/m2. These observations confirmed that the prepared materials have a big potential in the field of optoelectronics.

Impact of polyethylene glenoid cementation technique on cement mantle integrity and stability after cyclic loading: a computed tomography and biomechanical study.

There are no generally accepted guidelines for polyethylene (PE) glenoid component cementation techniques. In particular, it is not known whether the backside of a PE glenoid should be fully or partially cemented-or not cemented at all. We hypothesized that cementing techniques would have an impact on cement mantle volume and integrity, as well as biomechanical stability, measured as micromotion under cyclic loading. To address our hypothesis, 3 different cementation techniques using a single 2-peg PE glenoid design with polyurethane foam were compared regarding (1) the quality and quantity of the cement mantle and (2) biomechanical stability after cyclic loading invitro. Eight identically cemented glenoids per group were used. Group A underwent cement application only into the peg holes, group B received additional complete cement mantle application on the backside of the glenoid, and group C received the same treatment as group B but with additional standardized drill holes in the surface of the glenoid bone for extra cement interdigitation. All glenoids underwent cyclic edge loading by 105 cycles according to ASTM F2028-14. Before and after loading, cement mantle evaluation was performed by XtremeCT and biomechanical strength and loosening were evaluated by measuring the relative motion of the implants. The cement mantle at the back of the implant was incomplete in group A as compared with groups B and C, in which the complete PE backside was covered with a homogeneous cement mantle. The cement mantle was thickest in group C, followed by group B (P=.006) and group A (P<.001). We did not detect any breakage of the cement mantle in any of the 3 groups after testing. Primary stability during cyclic loading was similar in all groups after the "running-in" phase (up to 4000 cycles). Gross loosening did not occur in any implant. Coverage of the PE glenoid with cement was reproducible in the fully cemented groups (ie, groups B and C) as compared with relevant cement defects in group A. The addition of cement to the back of the PE glenoid and additional drill holes in the glenoid surface did not improve primary stability in the tested setting.

Improving thermoelectric performance of CuCrSe2 by manipulating the precipitated ferromagnetic spinel phase

As a superionic conductor, CuCrSe2 has recently attracted renewed attention in thermoelectric community for its phonon-liquid electron-crystal transport behaviours. Here, we demonstrate that the usually undesired second phase of ferromagnetic spinel CuCr2Se4 can play a significantly positive role in synergistically optimizing the thermoelectric properties of the CuCrSe2 compound. After systematically investigating the substitution behaviour of Ni for Cr, it is found that the contents of the ferromagnetic spinel phase can be controlled by virtue of the unique occupation preference of Ni in the tetrahedral and octahedral sites of CuCrSe2. A small amount of ferromagnetic CuCr2Se4 spinel phase essentially does not affect the weighted mobility but can act as carrier reservoirs in its ferromagnetic state, releasing additional holes into the matrix in the paramagnetic state. Furthermore, the presence of CuCr2Se4 precipitations in the CuCrSe2 matrix can drastically reduce the lattice thermal conductivity by generating extra phonon scattering mechanisms. Consequently, a zT value around 0.95, which is 33.8% higher than the absolutely pure sample, is achieved in the CuCr0·99Ni0·01Se2 sample with 3.64 wt% ferromagnetic spinel impurity.

Electronic structure and correlations in planar trilayer nickelate Pr4Ni3O8.

The discovery of superconductivity in planar nickelates raises the question of how the electronic structure and correlations of Ni1+ compounds compare to those of the Cu2+ cuprate superconductors. Here, we present an angle-resolved photoemission spectroscopy (ARPES) study of the trilayer nickelate Pr4Ni3O8, revealing a Fermi surface resembling that of the hole-doped cuprates but with critical differences. Specifically, the main portions of the Fermi surface are extremely similar to that of the bilayer cuprates, with an additional piece that can accommodate additional hole doping. We find that the electronic correlations are about twice as strong in the nickelates and are almost k-independent, indicating that they originate from a local effect, likely the Mott interaction, whereas cuprate interactions are somewhat less local. Nevertheless, the nickelates still demonstrate the strange-metal behavior in the electron scattering rates. Understanding the similarities and differences between these two families of strongly correlated superconductors is an important challenge.

Multi-beam ultrafast laser processing of free-standing nanofilms

In this study, femtosecond laser-based multi-beam interference laser processing on nanofilms with nanometer thicknesses was demonstrated. The resulting multi-hole, two-dimensional lattice pattern reflected a laser interference fringe formed on the surface of the nanofilm, with no breaks or cracks. In anticipation of the actual nanostructure fabrication, additional laser processing was performed to drill additional holes in the spaces between the existing holes, resulting in high-density multi-point hole drilling beyond the interference fringe pitch. Notably, processing materials with thicknesses close to 100 nm or less is difficult even with a state-of-the-art focused-ion-beam system. The presented method, in contrast, allows instantaneous, submicrometer-scale multi-point hole drilling of nanofilms over a large area, opening up a new frontier of nanoengineering. Future applications will include the fabrication of electron phase plates, membrane-based optomechanical devices, microelectromechanical systems, and engineering of atomic layer materials.

A new approach to enhance the thermoelectric performance of quaternary chalcogenides copper zinc tin sulfide thin films by varying copper molar concentration

This manuscript revealed an enhancement in the thermoelectric performance of quaternary chalcogenides Cu2ZnSnS4 (CZTS) TFs by the copper (Cu) atoms (1–2.5 mM) modulation during solution growth. Thermo-power data suggested that various performance parameters such as electrical conductivity (σ), Seebeck coefficient (S) and thermo-power factor (P) were improved significantly [(19–183 S/cm), (97–884 μV/°C) and (1.78 × 10−5–1.43 × 10−2 Wm−1K−2)] when the atomic concentration of Copper atoms increased from 01 to 2.5 mM respectively. This trend of thermo-power for CZTS thin films is correlate with development of additional holes along with the generation of Cu based secondary phases. The presence of extra/secondary phases due to additional Cu atoms is supported by some supplementary measurements. XRD data confirmed that some Cu based extra phases were developed at higher concentration of Cu atoms. Raman spectroscopy measurements further revealed that the intensity of Cu based extra/secondary phases was noticed towards higher values when the molar ratio of Cu atoms increased. SEM micrographs demonstrated the rougher surface of CZTS samples which were prepared using higher concentration of Cu when compared with lower concentration samples. UV/VIS Spectroscopy data further confirmed our argument that numbers of other secondary phases were expended with the concentration of Cu atoms.