Materials Today Physics最新文献

{"title":"Large electron-phonon drag asymmetry and reverse heat flow in the topological semimetal θ-TaN","authors":"Chunhua Li,&nbsp;David Broido","doi":"10.1016/j.mtphys.2025.101706","DOIUrl":"10.1016/j.mtphys.2025.101706","url":null,"abstract":"<div><div>A broad range of unusual transport behaviors have been discovered in topological semimetals. However, to date, the effect on the thermopower from intrinsic momentum exchange between electrons and phonons has received little attention. Here we report that huge electron-phonon drag enhancements of the thermopower of the topological semimetal, <span><math><mrow><mi>θ</mi></mrow></math></span>-phase tantalum nitride (<span><math><mrow><mi>θ</mi></mrow></math></span>-TaN), can occur that persist even up to room temperature. Our first principles calculations also identify a surprising asymmetry in which the large drag-enhanced thermopowers found slightly above the material's chemical potential disappear just below it. The large thermopower enhancements result from anomalous drag contributions from high frequency acoustic phonons with unusually small decay rates. The apparent vanishing drag results from (i) the emergence of an exceptionally high electrical conductivity promoted by the steep linear electronic dispersions extending below one of the topological nodal points; (ii) a remarkable cancellation in which momentum transferred from a charge current creates oppositely directed phonon heat currents of nearly equal magnitude, thereby masking the drag contributions. This extraordinary transport behavior is a consequence of an unusual interplay between intrinsic electron and phonon material properties in <span><math><mrow><mi>θ</mi></mrow></math></span>-TaN. Our work gives new insights into the fundamental physical properties of coupled electron-phonon systems and motivates further exploration of drag effects in semimetals.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"53 ","pages":"Article 101706"},"PeriodicalIF":10.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143653723","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":"MoS2-based quantum dot artificial synapses for neuromorphic computing","authors":"Gongjie Liu,&nbsp;Haoqi Liu,&nbsp;Feifan Fan,&nbsp;Yuefeng Gu,&nbsp;Lisi Wei,&nbsp;Xiaolin Xiang,&nbsp;Yuhao Wang,&nbsp;Qiuhong Li","doi":"10.1016/j.mtphys.2025.101703","DOIUrl":"10.1016/j.mtphys.2025.101703","url":null,"abstract":"<div><div>The advancement of deep learning has escalated computational requirements. Neuromorphic devices, particularly those based on memristors, present strong potential to meet these demands. However, current memristors face challenges such as a low on/off ratio and poor linearity, which hinder the progress of neuromorphic computing. Here, we propose a MoS₂-based quantum dot memristor, where the presence of quantum dots facilitates the formation and stability of conductive channels. The device exhibits narrow set and reset voltage distributions, with an on/off ratio reaching 10⁵ and multiple resistive states. Based on these multi-state characteristics, we achieved parallel image processing with various operators. The excitatory postsynaptic current (EPSC), spike-timing-dependent plasticity (STDP), paired-pulse facilitation (PPF), long-term potentiation (LTP), and long-term depression (LTD) characteristics of the device were tested, with the linearity of LTP and LTD being 0.21 and −0.25, respectively. Based on the good linearity of weight updates, we built an artificial neural network to recognize facial images with Gaussian, salt-and-pepper, and Poisson noise. At noise levels of 40 %, 48 %, and λ = 80, the recognition accuracy rates were still as high as 100 %, 100 %, and 97.33 %, respectively. This work provides a valuable reference for quantum dot-based neuromorphic computing.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"53 ","pages":"Article 101703"},"PeriodicalIF":10.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143640421","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":"Effect of plastic hot-rolling on thermoelectric properties in Ag2Se0.65S0.35 ductile materials","authors":"Shiqi Yang ,&nbsp;Jin Liu ,&nbsp;Xuefeng Zhao ,&nbsp;Pengfei Qiu ,&nbsp;Xun Shi","doi":"10.1016/j.mtphys.2025.101707","DOIUrl":"10.1016/j.mtphys.2025.101707","url":null,"abstract":"<div><div>Ag₂(S, Se) solid solutions near the morphotropic phase boundary (MPB) well integrate excellent room-temperature ductility and high thermoelectric (TE) performance together, showing the great potential for the usage in flexible thermoelectrics. However, their orthorhombic-monoclinic phase transition brings great difficulty to fabricate the Ag₂(S, Se)-based flexible films with high TE performance. In this work, taking the Ag₂Se_0.65S_0.35 which locates at the orthorhombic-monoclinic phase boundary as an example, we systematically investigate the evolutions of phase and electrical transport properties of Ag_2-<em>x</em>Se_0.65S_0.35 during the plastic hot-rolling and the following post-treatment processes. Significantly degraded power factor is observed with increasing the deformation degree, but it can be recovered back by post-treatment, i.e. firstly annealing at 353 K and then dipping in liquid nitrogen. Finally, high-performance flexible Ag₂Se_0.65S_0.35 film with a room-temperature power factor of 17.0 μWcm⁻¹K⁻² is successfully obtained, providing a promising candidate materials for the development of flexible TE device used in wearables.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"53 ","pages":"Article 101707"},"PeriodicalIF":10.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143640422","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":"High responsivity, ultra-flexible, self-driven solar-blind fibrous photoelectrochemical detector for seawater antibiotic detection","authors":"Gang Wu ,&nbsp;Kai Chen ,&nbsp;Yizhou Ni ,&nbsp;Chao Wu ,&nbsp;Jinsong Liu ,&nbsp;Haizheng Hu ,&nbsp;Xuehua Zhang ,&nbsp;Shunli Wang ,&nbsp;Fengmin Wu ,&nbsp;Zhengyuan Wu ,&nbsp;Daoyou Guo","doi":"10.1016/j.mtphys.2025.101702","DOIUrl":"10.1016/j.mtphys.2025.101702","url":null,"abstract":"<div><div>The detection of antibiotics in seawater is essential for ensuring the safety and sustainability of the marine environment. However, existing detection methods are hindered by limitations such as slow response times, complex operations, or high costs. In this study, we propose the omnidirectional growth of high-quality <em>α</em>-Ga₂O₃ nanopillar arrays on a flexible carbon nanotube fiber (CNTF) substrate to construct a self-powered fibrous photoelectrochemical sensor for antibiotic detection. Importantly, the device effectively mitigates signal interference from ambient light and seawater fluctuations due to its ultra-flexibility and solar-blind photoresponse characteristics. Specifically, a significant photoresponsivity of 61.6 mA/W, a detectivity of 3.03 × 10¹¹ Jones, and an external quantum efficiency of 30.1 % are obtained, which are surpassing the performance of most fibrous photodetectors. Moreover, the device with 360° omnidirectional detection capability exhibits no significant degradation of photoresponse during 2000 bending cycles or long-term continuous operation. Notably, under combined effects of enhancing the separation efficiency of photogenerated carriers by organic ions and competing for solar-blind UV light absorption between antibiotic molecules and Ga₂O₃, the <em>α</em>-Ga₂O₃@CNTF detector demonstrates the capability to detect sulfonamides, quinolones, and tetracyclines at various concentrations in seawater. This work provides valuable insights into developing high-performance, cost-effective, and user-friendly devices for advanced seawater antibiotic detection technology.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"53 ","pages":"Article 101702"},"PeriodicalIF":10.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143640426","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":"Smoothing Li transport via weak Metal-O bonds for improved ionic mobility in lithium lanthanum titanium oxide","authors":"Chengran Luo ,&nbsp;Yao Shen ,&nbsp;Songhe Zhang ,&nbsp;Cheng Han ,&nbsp;Hongyi Chen","doi":"10.1016/j.mtphys.2025.101704","DOIUrl":"10.1016/j.mtphys.2025.101704","url":null,"abstract":"<div><div>Lithium lanthanum titanate oxide (LLTO) presents significant potential as a solid electrolyte in all-solid-state Li-ion batteries. However, its ionic conductivity requires enhancement for broader applications. In this study, we conducted first-principles calculations to explore the impact of metal doping on LLTO's ionic mobility. LLTO showed uneven ionic diffusion characterized by singular Li-O bonds at certain intermediate states. Ni doping introduced additional electrons into the <em>b</em>₁∗ orbital of the Ti-O anti-bonding, weakening the Ti-O bond and strengthening the Li-O bond. The enhanced Li-O bond facilitated smoother ionic diffusion, reducing the barrier energy to 3.4 × 10⁻⁴ cm²/s for Ni-doped LLTO. Moreover, incorporating various metal dopants in LLTO consistently demonstrated that weaker metal-O bonds contributed to reduced barrier energies. This research underscores the efficacy of diminishing metal-O bonds to significantly boost ionic migration rates in solid-state electrolytes with a perovskite structure.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"53 ","pages":"Article 101704"},"PeriodicalIF":10.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143640427","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":"Two-dimensional Janus MoSeH with tunable charge density wave, superconductivity and topological properties","authors":"Chang-Hao Sui,&nbsp;Shu-Xiang Qiao,&nbsp;Hao Ding,&nbsp;Kai-Yue Jiang,&nbsp;Shu-Ying Shang,&nbsp;Hong-Yan Lu","doi":"10.1016/j.mtphys.2025.101698","DOIUrl":"10.1016/j.mtphys.2025.101698","url":null,"abstract":"<div><div>The coexistence and competition between the well-known quantum phenomena such as superconductivity, charge density wave (CDW), and band topology represent a cutting-edge frontier in the field of condensed matter physics. Two-dimensional (2D) Janus transition metal sulfide hydrides, a family of materials known for hosting diverse quantum phenomena, have drawn extensive attention recently. In this work, based on first-principles calculations, a novel member of this family, named 2H-MoSeH, is predicted. The pristine 2H-MoSeH exhibits CDW induced by electron–phonon coupling. Remarkably, this CDW state can be entirely suppressed under 2% biaxial compressive strain, giving rise to superconducting state with transition temperature (<span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span>) of 24 K. Moreover, CDW can also be suppresed by 0.15 hole doping per primitive cell, leading to superconductivity with a <span><math><msub><mrow><mi>T</mi></mrow><mrow><mi>c</mi></mrow></msub></math></span> of 17 K while simultaneously inducing a non-trivial band topology. The coexistence and tunable competition among superconductivity, CDW, and band topology in 2H-MoSeH establish it as an ideal platform for exploring novel quantum phenomena and designing new quantum devices.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"53 ","pages":"Article 101698"},"PeriodicalIF":10.0,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143631291","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":"Prediction of high-temperature superconductors with Tc up to 214.3 K in Mg-Zr-H ternary hydrides","authors":"Yujie Wang ,&nbsp;Kaige Hu ,&nbsp;Min Pan","doi":"10.1016/j.mtphys.2025.101695","DOIUrl":"10.1016/j.mtphys.2025.101695","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Ternary hydrides, with richer chemical compositions and structures compared to binary hydrides due to their high degrees of freedom, are expected to contain more candidates for high-&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mtext&gt;c&lt;/mtext&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; superconductors with remarkable properties including higher &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mtext&gt;c&lt;/mtext&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; and lower stabilizing pressures. In this work, the high-pressure structures, electronic properties, and superconductivity of MgZrH&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; (&lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;-6) ternary system are investigated by combining the prediction method of particle swarm optimization algorithm and first-principles calculations. We find thermodynamically stable structures for MgZrH&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, MgZrH&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, and MgZrH&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, respectively, while only metastable structures for &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;⩾&lt;/mo&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;. During the predicted structures, our analysis mainly focuses on &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;P&lt;/mi&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;mi&gt;c&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;-MgZrH&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̄&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;-MgZrH&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;P&lt;/mi&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̄&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;-MgZrH&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;F&lt;/mi&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̄&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;-MgZrH&lt;sub&gt;12&lt;/sub&gt;. &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;P&lt;/mi&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;/&lt;/mo&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;mi&gt;c&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;-MgZrH&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̄&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;-MgZrH&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;4&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; exhibit a low &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mtext&gt;c&lt;/mtext&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; of 0.006 K at 40 GPa and 0.95 K at ambient pressure, respectively, due to low electronic contribution from hydrogen at the Fermi level. &lt;span&gt;&lt;math&gt;&lt;mrow&gt;&lt;mi&gt;P&lt;/mi&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;mover&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;̄&lt;/mo&gt;&lt;/mrow&gt;&lt;/mover&gt;&lt;/mrow&gt;&lt;/math&gt;&lt;/span&gt;-MgZrH&lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;6&lt;/mn&gt;&lt;/mr","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"53 ","pages":"Article 101695"},"PeriodicalIF":10.0,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143631389","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":"A suspended InSe membrane-based metal-semiconductor junction with excellent performance via flexoelectricity","authors":"J.J. Wu ,&nbsp;Z.Z. He ,&nbsp;G.Q. Zuo ,&nbsp;L. Sun ,&nbsp;D. Tan ,&nbsp;C.L. Zhang","doi":"10.1016/j.mtphys.2025.101701","DOIUrl":"10.1016/j.mtphys.2025.101701","url":null,"abstract":"<div><div>Two-dimensional semiconductor (2DS) materials exhibit immense potential for flexible electronic and photoelectronic devices due to their ultra-thin structural features. This paper proposes a suspended 2DS-InSe membrane-based metal-semiconductor junction (MSJ) structure, specifically designed to induce non-uniform tensile strain. This configuration enables a significant flexoelectric-induced in-plane polarization field while mitigating substrate effects. The effect of strain-gradient-induced flexoelectric polarization field on the performance of the proposed 2DS-InSe membrane-based MSJ is investigated using the CAFM, PFM and KPFM modules to characterize current-voltage (<em>I</em>-<em>V</em>) characteristics, out-of-plane electromechanical response, and surface potential. The suspended 2DS-InSe with thickness of 60 nm demonstrates enhanced electromechanical and photoelectric responses, as well as increased output current, compared to the supported 2DS-InSe, attributed to the larger in-plane polarization induced by non-uniform tensile strain. Additionally, the in-plane (<span><math><mrow><msub><mi>f</mi><mn>1111</mn></msub><mo>=</mo><msub><mi>f</mi><mn>2222</mn></msub><mo>=</mo><mn>3.053</mn></mrow></math></span> nC/m, <span><math><mrow><msub><mi>f</mi><mn>1221</mn></msub><mo>=</mo><msub><mi>f</mi><mn>2112</mn></msub><mo>=</mo><mo>−</mo><mn>9.374</mn></mrow></math></span> nC/m) and the out-of-plane (<span><math><mrow><msub><mi>f</mi><mn>3113</mn></msub><mo>=</mo><msub><mi>f</mi><mn>3223</mn></msub><mo>=</mo><mo>−</mo><mn>0.0188</mn></mrow></math></span> nC/m, <span><math><mrow><msub><mi>f</mi><mn>3333</mn></msub><mo>=</mo><mo>−</mo><mn>0.1407</mn></mrow></math></span> nC/m) flexoelectric coefficients of the used 2DS-InSe are evaluated. This study demonstrates that that the electrical, electromechanical, and photoelectric properties of membrane-based MSJs can be mechanically tuned through the flexoelectric-induced polarization fields, offering valuable insights for the development of novel membrane-based devices utilizing 2DS materials.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"53 ","pages":"Article 101701"},"PeriodicalIF":10.0,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143618728","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":"Anomalous anisotropic magnetotransport behavior mediated by Fermi surface reconstruction in topological nodal line TiB2 single crystals","authors":"Ming Cheng ,&nbsp;Lanxin Liu ,&nbsp;Yu Zhao ,&nbsp;Yifan Deng ,&nbsp;Run Lv ,&nbsp;Ruihuan Lan ,&nbsp;Nan Zhou ,&nbsp;Yongqiang Pan ,&nbsp;Wenhai Song ,&nbsp;Yuyan Han ,&nbsp;Xuan Luo ,&nbsp;Yuping Sun","doi":"10.1016/j.mtphys.2025.101690","DOIUrl":"10.1016/j.mtphys.2025.101690","url":null,"abstract":"<div><div>Transition metal diborides (MB<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span>), characterized by their simple crystal lattice structure and wide linear dispersion range, serve as an ideal system for exploring novel topological states and anomalous physical properties. In this study, we report a temperature-induced Fermi surface reconstruction at around 100 K and the anomalous magnetotransport behaviors mediated by it in nodal line semimetal TiB<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> single crystals. The experimental evidence for the Fermi surface reconstruction comes from the following aspects: (i) a noticeable dip in the temperature-dependent Seebeck coefficient; (ii) a breakdown of the Kohler’s rule; (iii) abnormal changes of hole carriers at around 100 K; (iv) the sharp change of twofold symmetry in the angle-dependent magnetoresistance (ADMR) patterns. Through such a Fermi surface reconstruction, the anisotropic magnetotransport behavior of TiB<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> exhibits significant changes. At low temperatures, TiB<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> exhibits field orientation-dependent superlinear unsaturated MR, while at high temperatures it can transform to linear MR or sublinear MR depending on the direction of magnetic field. Finally, the possible origin of the Fermi surface was discussed. This work reveals the presence of Fermi surface reconstruction and provide a suitable platform for exploring the relationship between Fermi surface topology and anomalous magnetotransport phenomenon in topological semimetals.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"53 ","pages":"Article 101690"},"PeriodicalIF":10.0,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143599608","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":"Multiscale characterization of laser-induced defects in the production of heterojunction photovoltaic cells","authors":"Anacleto Proietti ,&nbsp;Luca Buccini ,&nbsp;Pierfrancesco Atanasio ,&nbsp;Chiara Mancini ,&nbsp;Giancarlo La Penna ,&nbsp;Corrado Di Conzo ,&nbsp;Francesco Mura ,&nbsp;Wajahat Khan ,&nbsp;Marco Galiazzo ,&nbsp;Nicola Frasson ,&nbsp;Alessandra Querci ,&nbsp;Daniele Passeri ,&nbsp;Marco Rossi","doi":"10.1016/j.mtphys.2025.101699","DOIUrl":"10.1016/j.mtphys.2025.101699","url":null,"abstract":"<div><div>Heterojunction (HJT) photovoltaic cells represent a significant advancement in solar technology due to their ability to combine high efficiency with durability. However, the integration of shingling technology, a process which employs precise laser cutting to maximize panel performance, introduces substantial challenges. The utilization of nanosecond infrared (ns-IR) lasers for segmentation often results in structural and morphological damage, particularly along the cut edges, thereby impacting the optical, mechanical, and electrical properties of the cells.</div><div>This study employs advanced multi-scale characterisation techniques, including scanning electron microscopy (SEM), Raman spectroscopy, photoluminescence (PL) analysis, and atomic force microscopy (AFM), to investigate these laser-induced defects. The results reveal extensive disruptions to the surface morphology, including the formation of silicon oxide residues and deformation of pyramidal structures essential for light trapping. Raman and PL analyses highlight strain and disorder within the silicon lattice, particularly near the cut edges, where defects reduce crystalline quality and increase recombination losses. Additionally, Kelvin Probe Force Microscopy (KPFM) measurements indicate a significant decline in surface potential and work function, extending up to millimeters from the cut region, further compromising cell efficiency. These findings emphasize the critical need to optimize laser cutting processes for HJT cells, particularly in shingling applications. Achieving this objective necessitates minimizing defects and preserving the integrity of silicon and indium tin oxide layers, thereby facilitating the fabrication of high-performing solar cells that can be scaled up for application in more efficient and reliable photovoltaic solutions.</div></div>","PeriodicalId":18253,"journal":{"name":"Materials Today Physics","volume":"53 ","pages":"Article 101699"},"PeriodicalIF":10.0,"publicationDate":"2025-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143590112","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}