Materials Today Physics最新文献

{"title":"Simultaneous bright singlet and triplet emissions in CsPbBr3 nanocrystals for next-generation light sources","authors":"Youngsin Park ,&nbsp;Atanu Jana ,&nbsp;Sangeun Cho ,&nbsp;Robert A. Taylor ,&nbsp;Geunsik Lee","doi":"10.1016/j.mtphys.2025.101839","DOIUrl":"10.1016/j.mtphys.2025.101839","url":null,"abstract":"<div><div>Lead halide perovskite nanocrystals exhibit excellent optoelectronic properties, yet simultaneous observation of bright singlet and triplet exciton emissions under identical conditions has remained elusive. This limitation hinders optimization of quantum efficiency in light-emitting devices. Here, we provide the direct spectroscopic evidence for coexisting bright singlet and triplet excitons in CsPbBr₃ nanocrystals, overcoming the conventional 25 % spin-statistical efficiency ceiling. Using polarization-resolved, spatially resolved, and time-resolved micro-photoluminescence at 7 K, we resolve three sharp triplet fine-structure components (T1, T2, T3) with energy separations of 1–3 meV and linear polarization &gt;85 %, coexisting with broad singlet emission. The triplet emissions display distinct polarization axes, nonlinear intensity scaling, and nanosecond lifetimes, confirming their assignment as Rashba-split bright triplet states. Spatial mapping reveals that these emissions arise from structurally pristine domains with exciton diffusion lengths exceeding 9 μm. Time-resolved measurements show concurrent fast and slow decay components, consistent with singlet-to-triplet intersystem crossing followed by radiative triplet recombination. Our findings establish a comprehensive picture of exciton spin dynamics in perovskite nanocrystals and open new avenues for spin-engineered photonic devices. This work lays the foundation for next-generation LEDs, lasers, and quantum light sources that leverage both singlet and triplet radiative channels to exceed traditional efficiency limits. While these findings are demonstrated at cryogenic temperatures, they highlight essential spin-related mechanisms that could be harnessed for room-temperature operation through enhanced Rashba coupling, dielectric engineering, or compositional tuning.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"57 ","pages":"Article 101839"},"PeriodicalIF":9.7,"publicationDate":"2025-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144857905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anharmonic rattling vibrations and multivalley bands in enabling Zintl-phase YbZn2X2 (X = As, Sb) thermoelectrics","authors":"Zhiwei Zhang ,&nbsp;Shuwei Tang ,&nbsp;Shulin Bai ,&nbsp;Da Wan ,&nbsp;Peng Ai ,&nbsp;Pengfei Zhang ,&nbsp;Zhanpeng Xu ,&nbsp;Yujie Bao ,&nbsp;Yunzhuo Zhang","doi":"10.1016/j.mtphys.2025.101837","DOIUrl":"10.1016/j.mtphys.2025.101837","url":null,"abstract":"<div><div>The design of high-performance thermoelectric (TE) materials requires the delicate balancing of inherently competing electronic and thermal transport properties. In this work, a comprehensive theoretical investigation of the Zintl-phase YbZn₂X₂ (X = As, Sb) materials is explored through first-principles calculations and Boltzmann transport theory, which simultaneously achieves a favorable confluence of high electronic transport efficiency and intrinsically low lattice thermal conductivity. The YbZn₂X₂ (X = As, Sb) materials possess direct band gaps of 1.23 eV and 0.39 eV using Heyd-Scuseria-Ernzerhof (HSE06) hybrid functional, respectively. Weak crystal field effects suppress the splitting of valence bands, which enhance band degeneracy. The conduction bands exhibit multi-valley characteristics, promoting high carrier mobility and power factor. Moreover, flat phonon dispersion curves reduce phonon group velocities of YbZn₂X₂ (X = As, Sb) materials, and “rattling-like” vibrations of Zn atom and asymmetric Zn-X (X = As, Sb) bonds induce pronounced lattice anharmonicity. These characteristics effectively suppress thermal transport, which reduce the lattice thermal conductivities of YbZn₂As₂ and YbZn₂Sb₂ to 1.59 W/mK and 0.94 W/mK at 700 K, respectively. Consequently, the <em>n</em>-type doping YbZn₂As₂ and YbZn₂Sb₂ materials achieve the dimensionless figure of merits (<em>ZT</em>) of 0.62 and 0.75 @ 700 K, respectively, showing a synergistic optimization of the electronic structure and phonon scattering mechanisms. Notably, the predicted thermoelectric performance of YbZn₂Sb₂ is in excellent agreement with experimental measurements, affirming the robustness of the computational framework. These findings not only shed light on the fundamental coupling between electronic and lattice dynamics in Zintl-phase YbZn₂As₂ and YbZn₂Sb₂ materials, but also provide a predictive design strategy for next-generation TE materials with high performance.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"57 ","pages":"Article 101837"},"PeriodicalIF":9.7,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144851709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal processing-induced domain reconfiguration and property enhancement in BiFeO3–BaTiO3 ceramics for high temperature applications","authors":"Bing Wang ,&nbsp;Ziqi Yang ,&nbsp;Xiaodong Liu ,&nbsp;Yizhe Li ,&nbsp;Andreas Wohninsland ,&nbsp;Lalitha Kodumudi Venkataraman ,&nbsp;Bingying Xie ,&nbsp;Annette Kleppe ,&nbsp;David A. Hall","doi":"10.1016/j.mtphys.2025.101836","DOIUrl":"10.1016/j.mtphys.2025.101836","url":null,"abstract":"<div><div>High temperature ferroelectric ceramics have generated significant interest in recent years, from both a fundamental perspective and for practical applications as temperature-stable dielectrics or piezoelectric transducers. Particularly, BiFeO₃-BaTiO₃ ceramics show great promise as a replacement for lead-based materials in demanding environments. In the present study, as-sintered BiFeO₃-BaTiO₃ ceramics are subjected to different heat treatment conditions (annealing and quenching processes) and poling procedures to evaluate their influence on the domain configuration and functional properties. As a result, the modified 0.7BiFeO₃-0.3BaTiO₃ ceramics were found to exhibit a remanent polarization of 0.44 C m⁻² at 100 °C, a Curie temperature of 500 °C and planar electromechanical coupling factor of 0.6 near the depolarization temperature of 480 °C after quenching at 800 °C in air; these materials show excellent potential for applications in high temperature piezoelectric transducers. In-situ temperature-dependent X-ray diffraction studies revealed unusual enhancement of the rhombohedral distortion on heating to temperatures ∼200 °C, associated with re-entrant relaxor ferroelectric behaviour. The ferroelectric domain configuration evolved from a disordered nanodomain structure in the as-sintered ceramic to a more structured herringbone-type nano-domain structure for the quenched sample, comprising a mixture of 180° and non-180° domain walls. Subsequent direct current poling led to a pronounced increase in domain size for both annealed and quenched samples, forming well-oriented lamellar domains and resulting in enhancement of ferroelectricity. High energy synchrotron X-ray diffraction experiments demonstrated a high degree of domain alignment along the electric field direction, resulting in a domain orientation fraction of ∼93 % for &lt;222&gt;-oriented grains in the heat-treated samples. Significant enhancement of the total electrostrain upon heating from room temperature to 100 °C was attributed to a combination of the increased extrinsic domain switching contribution, due to the enhancement of spontaneous strain, together with a higher intrinsic electrostrictive lattice strain.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"57 ","pages":"Article 101836"},"PeriodicalIF":9.7,"publicationDate":"2025-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144824985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulations studies of avalanche multiplication effect in avalanche-luminescence dual-action structure for noncarrier injection Nano-LED","authors":"Wenhao Li ,&nbsp;Shuqian Zhang ,&nbsp;Xiangyao Zeng ,&nbsp;Xiongtu Zhou ,&nbsp;Yongai Zhang ,&nbsp;Tailiang Guo ,&nbsp;Chaoxing Wu","doi":"10.1016/j.mtphys.2025.101835","DOIUrl":"10.1016/j.mtphys.2025.101835","url":null,"abstract":"<div><div>As an emerging driving mode based on the principle of electrostatic induction, the noncarrier injection (NCI) mode is expected to propel micro/nano-based light-emitting display technology toward a future that is more immersive, intelligent, and integrated. However, the further improvement of electroluminescence efficiency is a problem to be solved urgently at present for the nanoscale light-emitting diode (nLED) operating in NCI mode. In this work, the avalanche multiplication effect in the NCI-nLED is investigated through finite element simulations. The carriers generated by the avalanche effect play a key role in enhancing the performance of NCI-nLED is revealed. The dynamic variation of carrier concentration and the energy band is studied to analyze the generation process of the avalanche effect and the mechanism of noncarrier electroluminescence enhancement. Importantly, we propose a potentially ultra-simple symmetrical structure characterized by two single-quantum wells (QWs) avalanche junctions, where a single-QW functions as both the avalanche layer and the luminescence layer. It is demonstrated that the electroluminescence intensity of this structure can be increased to 14.19 times compared with that of original structure. The simulation work advances the theoretical model for understanding the NCI mode and opens a new perspective for the application expansion of display technology.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"57 ","pages":"Article 101835"},"PeriodicalIF":9.7,"publicationDate":"2025-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144819747","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine learning models for predicting the hydrogenic impurity nonlinear optical rectification in GaAs/AlGaAs Tetrapod core/shell quantum dots under the effect of temperature","authors":"A. Cherni ,&nbsp;N. Zeiri ,&nbsp;David B. Hayrapetyan ,&nbsp;A. Ed-Dahmouny ,&nbsp;M.E. El Sayed ,&nbsp;A. Samir ,&nbsp;C.A. Duque","doi":"10.1016/j.mtphys.2025.101833","DOIUrl":"10.1016/j.mtphys.2025.101833","url":null,"abstract":"<div><div>In this study, we investigate the nonlinear optical rectification (NOR) between the first and excited states in GaAs/AlGaAs Tetrapod Core/Shell Quantum Dots (TCSQDs) under the effect of temperature, using the compact density matrix formalism. The energy levels and wave functions are computed by solving the Schrödinger equation with the Finite Element Method (FEM) within the framework of the effective mass approximation (EMA). The objective of the present study is to develop an accurate and efficient method for modelling and predicting the NOR coefficient related to E₂₃ transition, taking into account the influence of temperature variations on the quantum dot system. To achieve this, we apply a range of machine learning (ML) algorithms, including Artificial Neural Networks (ANN), Decision Tree (DT), and Random Forest Regression (RFR). Among these, Random Forest Regression yields the best performance, achieving R² = 0.99940, MSE = 1.10 × 10⁻⁴, and MAE = 0.00510 at room temperature. The importance of this work lies in its potential to provide valuable insights for neither designing advanced quantum dot-based optoelectronic devices, such as infrared detectors and photonic components, where temperature-dependent NOR are properties crucial for performance optimization. Furthermore, the application of ML techniques in this context offers a promising approach for efficient and accurate modelling of complex quantum systems, facilitating the development of future quantum technologies.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"58 ","pages":"Article 101833"},"PeriodicalIF":9.7,"publicationDate":"2025-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144813254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetic field and pressure-tuned Fermi liquid in heavy-fermion alloy Eu2ZnSb2","authors":"Feng-Xian Bai ,&nbsp;Zi-Yu Cao ,&nbsp;Chen Chen ,&nbsp;Hao Yu ,&nbsp;Di Peng ,&nbsp;Ya-Kang Peng ,&nbsp;Ge Huang ,&nbsp;Liu-Cheng Chen ,&nbsp;Hong Xiao ,&nbsp;Qian Zhang ,&nbsp;Xiao-Jia Chen","doi":"10.1016/j.mtphys.2025.101823","DOIUrl":"10.1016/j.mtphys.2025.101823","url":null,"abstract":"<div><div>Quantum phase transitions are explored in many materials, among which heavy-fermion compounds are the most prominent. Previous studies have shown that different types of transitions in a heavy-fermion compound can be tuned by an external variable, such as (chemical or physical) pressure and magnetic fields. Here we identify a new heavy-fermion alloy Eu₂Zn_0.98Sb₂ as exhibiting a pressure and magnetic field-induced quantum phase transition. An antiferromagnetic order, an extreme large electronic specific heat coefficient, and a Kondo behavior are evident in magnetic susceptibility, specific heat, and resistivity measurements. The Fermi liquid behavior appears after the antiferromagnetic order and Kondo effect gradually suppressed by external magnetic field and pressure, revealing two possible quantum critical phenomenon in Eu₂Zn_0.98Sb₂. A grend-KW ratio <span><math><mover><mrow><mi>A</mi></mrow><mrow><mo>̃</mo></mrow></mover></math></span>/<span><math><mover><mrow><mi>γ</mi></mrow><mrow><mo>̃</mo></mrow></mover></math></span> was then obtained, which is close to that of heavy-fermions. Our findings provide a unique observation of the heavy-fermion behavior in a Eu-based compound.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"57 ","pages":"Article 101823"},"PeriodicalIF":9.7,"publicationDate":"2025-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144802754","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermally Stable Negative Permittivity and Fano like Resonance in Multi-Doped Manganite","authors":"H. Salhi, W. Aloui, A. Mleiki, H. Rahmouni","doi":"10.1016/j.mtphys.2025.101826","DOIUrl":"https://doi.org/10.1016/j.mtphys.2025.101826","url":null,"abstract":"We report an atypical dielectric behavior of a newly synthesized A-site multi-doped La_0.4Bi_0.3Sr_0.2Ba_0.1MnO₃ manganite, which has not been reported previously. The material exhibits a thermally robust negative real permittivity across a broad frequency (10 KHz-100MHz) and temperature range (230K-400K). This is interpreted as result of a collective plasmonic state of free electrons and modeled according to the Drude formalism. Dielectric losses exhibit exceptionally low values and tanδ reaches notable minima (0.0002&lt;tanδ&lt;0.01). A striking feature is a double zero-crossing of real permittivity around 40 MHz which emerges from the interplay between slow interfacial polarization and fast grain response. This previously unreported phenomenon<strong>,</strong> in single-phase manganites, suggests a Fano-Like resonance modeled according to the Lorentz-Drude formalism. Furthermore, the imaginary permittivity exhibits negative values at high frequencies, a phenomenon rarely observed in natural materials. These combined phenomena, unprecedented in this material class, position La_0.4Bi_0.3Sr_0.2Ba_0.1MnO₃ as a unique functional oxide with high potential for applications in metamaterials, near-zero permittivity structures, and electromagnetic wave modulators.","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"737 1","pages":""},"PeriodicalIF":11.5,"publicationDate":"2025-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144797427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flexible, transparent, arrayable interdigitated electrode-based micro-supercapacitor with tunable voltage/current windows","authors":"Daosen Song,&nbsp;Guangming Zhang,&nbsp;Kai Shi,&nbsp;Peikai Duan,&nbsp;Jie Huang,&nbsp;Yice Wang,&nbsp;Huifa Shi,&nbsp;Hongbo Lan","doi":"10.1016/j.mtphys.2025.101830","DOIUrl":"10.1016/j.mtphys.2025.101830","url":null,"abstract":"<div><div>Flexible transparent micro-supercapacitors (FTMSCs) have emerged as a key resource due to their high transmittance, durable mechanical flexibility, and excellent electrochemical performance. However, due to the limitations imposed by electrode materials and fabrication processes, the voltage window of most reported supercapacitors remains relatively low (typically below 1 V) and lacks tunability. Therefore, this study reveals an innovative method for preparing PPy/Au/Ag-wall FTMSCs using micro-3D printing combined with directional electrochemical polymerisation (ECP). By employing a high-resolution multilayer Ag-wall electrode structure and optimising the polymerisation process of polypyrrole (PPy) on the Ag-wall, the FTMSCs with a transmittance of approximately 80.07 %, an areal capacitance of 23.36 mF cm⁻², and an energy density of 3.24 μWh cm⁻² have been successfully fabricated. The results demonstrated excellent performance under various bending conditions, with a capacitance retention rate of 90.6 % after 1000 bending cycles. Additionally, the flexible adjustment of the voltage window was achieved through series and parallel connections of the Ag-wall within a limited area of 0.685 cm², enabling a voltage range from 1 V to 6 V and high output power. The fabricated FTMSC provides a promising foundation for the application in low-cost, large-scale wearable and high-performance electronic devices.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"57 ","pages":"Article 101830"},"PeriodicalIF":9.7,"publicationDate":"2025-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144797430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lone pair electrons and undersized atoms mediate anomalous thermal conductivity in TlSe-type ABX2 compounds","authors":"Zhengtong Xue ,&nbsp;Yiyang Sun ,&nbsp;Jiawei Zhang","doi":"10.1016/j.mtphys.2025.101832","DOIUrl":"10.1016/j.mtphys.2025.101832","url":null,"abstract":"<div><div>Crystalline materials with intrinsically low lattice thermal conductivity (<em>κ</em>_L) are crucial for thermoelectric and thermal insulating applications. In recent years, TlSe-type ABX₂ compounds have attracted considerable attention owing to their ultralow <em>κ</em>_L, typically attributed to rattling cations with lone pair electrons. However, a systematic understanding of the microscopic mechanisms governing thermal transport trends in these structures remains elusive. Combining first-principles calculations and analysis, we reveal distinct and synergistic roles of lone pair electrons and atomic size effects in suppressing <em>κ</em>_L. Counterintuitively, introducing lone pair electrons (A = Ga, In, Tl) reverses conventional mass-dependent trends, increasing <em>κ</em>_L with average atomic mass due to enhanced anharmonicity related to lone pair activity evidenced by large Grüneisen parameters and reduced phonon lifetimes. Conversely, in systems lacking lone pairs, atomic size effects dominate; undersized atoms (e.g., Na⁺ in NaInTe₂) induce strong anharmonicity, yielding lower <em>κ</em>_L (∼1.33 W m⁻¹ K⁻¹) than heavier analogs (RbInTe₂, ∼1.45 W m⁻¹ K⁻¹). Strikingly, the synergy of lone pair electrons and undersized atoms in GaInTe₂ amplifies phonon scattering, achieving lower <em>κ</em>_L (∼0.58 W m⁻¹ K⁻¹) than that of InTe (∼0.64 W m⁻¹ K⁻¹). This work elucidates the competing mechanisms in ABX₂ systems and establishes a dual design strategy—leveraging lone pair electrons and atomic size mismatch—for engineering materials with intrinsically ultralow thermal conductivity.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"57 ","pages":"Article 101832"},"PeriodicalIF":9.7,"publicationDate":"2025-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144797429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plasma modification induced interface engineering enhanced GaN UV photodetectors with ultrahigh performance and bias-tuned selective response","authors":"Shihao Fu, Danyang Xia, Yuefei Wang, Yurui Han, Chong Gao, Youheng Song, Bingsheng Li, Zhipeng Wei, Aidong Shen","doi":"10.1016/j.mtphys.2025.101831","DOIUrl":"https://doi.org/10.1016/j.mtphys.2025.101831","url":null,"abstract":"Deficient assembly of interfaces often results in considerable leakage current and compromised device performance, therefore, interface engineering strategy has emerged as a crucial aspect of device fabrication. In this work, the metal/semiconductor (M/S) interface was modified by single-sided plasma etching to fabricate an asymmetric M/S contact GaN-based photodetector (PD). Compared to untreated GaN-based PD, the GaN-based PD with interface engineering exhibits superior performance with an ultrahigh light-dark current ratio of 9.35 × 10⁹ and a high detectivity of 5.64 × 10¹⁷ Jones. Even considering noise effects, the detectivity value remains high at ∼10¹⁶ Jones, which is comparable to photomultiplier tubes. The performance improvement is attributed to the passivation of GaN interface dangling bonds by plasma treatment, while the localized N vacancies induced by etching act as shallow donor energy levels in the GaN energy band structure, reducing the barrier height of the interface and increasing the transport efficiency of charge carriers. In addition, by affecting the depletion layer width of the M/S interface, the device gains a bias-tuned selective response (UVC, UV-C to A, UVA waveband), which can meet various application requirements. Consequently, intentionally introducing local defects via interface engineering is an efficient strategy to optimize device performance while serving as a reference for future device design.","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"3 1","pages":""},"PeriodicalIF":11.5,"publicationDate":"2025-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144802791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}