arXiv - PHYS - Mesoscale and Nanoscale Physics最新文献_第4页

Pursuing high-fidelity control of spin qubits in natural Si/SiGe quantum dot 在天然硅/硅锗量子点中实现自旋量子比特的高保真控制

arXiv - PHYS - Mesoscale and Nanoscale Physics Pub Date : 2024-09-15 DOI: arxiv-2409.09747

Ning Wang, Shao-Min Wang, Run-Ze Zhang, Jia-Min Kang, Wen-Long Lu, Hai-Ou Li, Gang Cao, Bao-Chuan Wang, Guo-Ping Guo

{"title":"Pursuing high-fidelity control of spin qubits in natural Si/SiGe quantum dot","authors":"Ning Wang, Shao-Min Wang, Run-Ze Zhang, Jia-Min Kang, Wen-Long Lu, Hai-Ou Li, Gang Cao, Bao-Chuan Wang, Guo-Ping Guo","doi":"arxiv-2409.09747","DOIUrl":"https://doi.org/arxiv-2409.09747","url":null,"abstract":"Electron spin qubits in silicon are a promising platform for fault-tolerant\u0000quantum computing. Low-frequency noise, including nuclear spin fluctuations and\u0000charge noise, is a primary factor limiting gate fidelities. Suppressing this\u0000noise is crucial for high-fidelity qubit operations. Here, we report on a\u0000two-qubit quantum device in natural silicon with universal qubit control,\u0000designed to investigate the upper limits of gate fidelities in a non-purified\u0000Si/SiGe quantum dot device. By employing advanced device structures, qubit\u0000manipulation techniques, and optimization methods, we have achieved\u0000single-qubit gate fidelities exceeding 99% and a two-qubit Controlled-Z (CZ)\u0000gate fidelity of 91%. Decoupled CZ gates are used to prepare Bell states with a\u0000fidelity of 91%, typically exceeding previously reported values in natural\u0000silicon devices. These results underscore that even natural silicon has the\u0000potential to achieve high-fidelity gate operations, particularly with further\u0000optimization methods to suppress low-frequency noise.","PeriodicalId":501137,"journal":{"name":"arXiv - PHYS - Mesoscale and Nanoscale Physics","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Absence of heat flow in ν = 0 quantum Hall ferromagnet in bilayer graphene 双层石墨烯中 ν = 0 量子霍尔铁磁体无热流

arXiv - PHYS - Mesoscale and Nanoscale Physics Pub Date : 2024-09-15 DOI: arxiv-2409.09663

Ravi Kumar, Saurabh Kumar Srivastav, Ujjal Roy, Ujjawal Singhal, K. Watanabe, T. Taniguchi, Vibhor Singh, P. Roulleau, Anindya Das

{"title":"Absence of heat flow in ν = 0 quantum Hall ferromagnet in bilayer graphene","authors":"Ravi Kumar, Saurabh Kumar Srivastav, Ujjal Roy, Ujjawal Singhal, K. Watanabe, T. Taniguchi, Vibhor Singh, P. Roulleau, Anindya Das","doi":"arxiv-2409.09663","DOIUrl":"https://doi.org/arxiv-2409.09663","url":null,"abstract":"The charge neutrality point of bilayer graphene, denoted as {nu} = 0 state,\u0000manifests competing phases marked by spontaneously broken isospin\u0000(spin/valley/layer) symmetries under external magnetic and electric fields.\u0000However, due to their electrically insulating nature, identifying these phases\u0000through electrical conductance measurements remains challenging. A recent\u0000theoretical proposal introduces a novel approach, employing thermal transport\u0000measurements to detect these competing phases. Here, we experimentally explore\u0000the bulk thermal transport of the {nu} = 0 state in bilayer graphene to\u0000investigate its ground states and collective excitations associated with\u0000isospin. While the theory anticipates a finite thermal conductance in the {nu}\u0000= 0 state, our findings unveil an absence of detectable thermal conductance.\u0000Through variations in the external electric field and temperature-dependent\u0000measurements, our results suggest towards gapped collective excitations at\u0000{nu} = 0 state. Our findings underscore the necessity for further\u0000investigations into the nature of {nu} = 0.","PeriodicalId":501137,"journal":{"name":"arXiv - PHYS - Mesoscale and Nanoscale Physics","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Highly tunable 2D silicon quantum dot array with coupling beyond nearest neighbors 超越近邻耦合的高可调二维硅量子点阵列

arXiv - PHYS - Mesoscale and Nanoscale Physics Pub Date : 2024-09-15 DOI: arxiv-2409.09761

Ning Wang, Jia-Min Kang, Wen-Long Lu, Shao-Min Wang, You-Jia Wang, Hai-Ou Li, Gang Cao, Bao-Chuan Wang, Guo-Ping Guo

引用次数: 0

Scalable Reshaping of Diamond Particles via Programmable Nanosculpting 通过可编程纳米雕刻实现金刚石颗粒的可扩展重塑

arXiv - PHYS - Mesoscale and Nanoscale Physics Pub Date : 2024-09-14 DOI: arxiv-2409.09393

Tongtong Zhang, Fuqiang Sun, Yaorong Wang, Yingchi Li, Jing Wang, Zhongqiang Wang, Kwai Hei Li, Ye Zhu, Qi Wang, Lei Shao, Ngai Wong, Dangyuan Lei, Yuan Lin, Zhiqin Chu

{"title":"Scalable Reshaping of Diamond Particles via Programmable Nanosculpting","authors":"Tongtong Zhang, Fuqiang Sun, Yaorong Wang, Yingchi Li, Jing Wang, Zhongqiang Wang, Kwai Hei Li, Ye Zhu, Qi Wang, Lei Shao, Ngai Wong, Dangyuan Lei, Yuan Lin, Zhiqin Chu","doi":"arxiv-2409.09393","DOIUrl":"https://doi.org/arxiv-2409.09393","url":null,"abstract":"Diamond particles have many interesting properties and possible applications.\u0000However, producing diamond particles with well-defined shapes at scale is\u0000challenging because diamonds are chemically inert and extremely hard. Here, we\u0000show air oxidation, a routine method for purifying diamonds, can be used to\u0000precisely shape diamond particles at scale. By exploiting the distinct\u0000reactivities of different crystal facets and defects inside the diamond,\u0000layer-by-layer outward-to-inward and inward-to-outward oxidation produced\u0000diverse diamond shapes including sphere, twisted surface, pyramidal islands,\u0000inverted pyramids, nano-flowers, and hollow polygons. The nanosculpted diamonds\u0000had more and finer features that enabled them to outperform the original raw\u0000diamonds in various applications. Using experimental observations and Monte\u0000Carlo simulations, we built a shape library that guides the design and\u0000fabrication of diamond particles with well-defined shapes and functional value.\u0000Our study presents a simple, economical and scalable way to produce\u0000shape-customized diamonds for various photonics, catalysis, quantum and\u0000information technology applications.","PeriodicalId":501137,"journal":{"name":"arXiv - PHYS - Mesoscale and Nanoscale Physics","volume":"100 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253649","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Intrinsic nonlinear conductivity induced by quantum geometry in altermagnets and measurement of the in-plane Néel vector 改变磁体中量子几何诱导的内在非线性传导性以及平面内奈尔矢量的测量

arXiv - PHYS - Mesoscale and Nanoscale Physics Pub Date : 2024-09-14 DOI: arxiv-2409.09241

Motohiko Ezawa

引用次数: 0

Quantum Hall effect and zero plateau in bulk HgTe 块状碲镉汞的量子霍尔效应和零高原

arXiv - PHYS - Mesoscale and Nanoscale Physics Pub Date : 2024-09-14 DOI: arxiv-2409.09409

M. L. Savchenko, D. A. Kozlov, S. S. Krishtopenko, N. N. Mikhailov, Z. D. Kvon, A. Pimenov, D. Weiss

引用次数: 0

First-principles study of structural, electronic and optical properties of non-toxic RbBaX$_3$ (X = F, Cl, Br, I) perovskites under hydrostatic pressure 静水压力下无毒 RbBaX$_3$ (X = F, Cl, Br, I) 包晶石结构、电子和光学特性的第一性原理研究

arXiv - PHYS - Mesoscale and Nanoscale Physics Pub Date : 2024-09-14 DOI: arxiv-2409.09524

Pranti Saha, In Jun Park, Protik Das, Fariborz Kargar

{"title":"First-principles study of structural, electronic and optical properties of non-toxic RbBaX$_3$ (X = F, Cl, Br, I) perovskites under hydrostatic pressure","authors":"Pranti Saha, In Jun Park, Protik Das, Fariborz Kargar","doi":"arxiv-2409.09524","DOIUrl":"https://doi.org/arxiv-2409.09524","url":null,"abstract":"We have investigated the structural, mechanical, electronic and optical\u0000properties of Rb-based cubic perovskite RbBaX$_3$ (X = F, Cl, Br, I) under\u0000hydrostatic pressure, using first-principle density functional theory (DFT).\u0000All RbBaX$_3$ perovskites exhibit thermodynamic and mechanical stability at\u0000ambient pressure. RbBaF$_3$ remains structurally stable across all examined\u0000pressures, while RbBaCl$_3$, RbBaBr$_3$, and RbBaI$_3$ maintain mechanical\u0000stability up to 60, 60, and 40 GPa, respectively. These materials are ductile\u0000even at elevated pressure. RbBaF$_3$ has a direct bandgap of 4.80 eV while\u0000other compositions exhibit indirect band gaps of 4.37, 3.73, and 3.24 eV with\u0000halide atoms of Cl, Br, and I, respectively. Under elevated hydrostatic\u0000pressure, only RbBaCl$_3$ and RbBaI$_3$ exhibit an indirect-to direct band\u0000transition while others preserve their nature of band gap. Our results show\u0000that spin-orbit coupling significantly affects only the valance bands of\u0000larger-sized halides (Cl, Br, I). With hybrid functional (HSE) correction, the\u0000band gaps of these four materials increase to 6.7, 5.6, 4.8 and 4.4 eV,\u0000respectively, but the nature of direct/indirect band transition remains\u0000unchanged. Orbital-decomposed partial density of states calculation reveals\u0000that the halogen p-orbitals dominate the valence band near the Fermi level,\u0000while Rb 5s-orbital affects the conduction band minima the most. Investigation\u0000of the optical properties reveals wide-band absorption, low electron loss,\u0000moderate reflectivity and lower refractive index in the UV to deep-UV range.\u0000The strength and range of absorption increases significantly with hydrostatic\u0000pressure, suggesting that RbBaX$_3$ perovskites are promising candidates for\u0000tunable UV-absorbing optoelectronic devices.","PeriodicalId":501137,"journal":{"name":"arXiv - PHYS - Mesoscale and Nanoscale Physics","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Nonlocal conductance of a Majorana wire near the topological transition 拓扑转变附近马约拉纳线的非局部电导率

arXiv - PHYS - Mesoscale and Nanoscale Physics Pub Date : 2024-09-14 DOI: arxiv-2409.09325

Vladislav D. Kurilovich, William S. Cole, Roman M. Lutchyn, Leonid I. Glazman

引用次数: 0

Increased Brightness and Reduced Efficiency Droop in Perovskite Quantum Dot Light-Emitting Diodes using Carbazole-Based Phosphonic Acid Interface Modifiers 使用咔唑基膦酸界面改性剂提高过氧化物量子点发光二极管的亮度并降低效率骤降

arXiv - PHYS - Mesoscale and Nanoscale Physics Pub Date : 2024-09-14 DOI: arxiv-2409.09556

Gillian Shen, Yadong Zhang, Julisa Juarez, Hannah Contreras, Collin Sindt, Yiman Xu, Jessica Kline, Stephen Barlow, Elsa Reichmanis, Seth R. Marder, David S. Ginger

{"title":"Increased Brightness and Reduced Efficiency Droop in Perovskite Quantum Dot Light-Emitting Diodes using Carbazole-Based Phosphonic Acid Interface Modifiers","authors":"Gillian Shen, Yadong Zhang, Julisa Juarez, Hannah Contreras, Collin Sindt, Yiman Xu, Jessica Kline, Stephen Barlow, Elsa Reichmanis, Seth R. Marder, David S. Ginger","doi":"arxiv-2409.09556","DOIUrl":"https://doi.org/arxiv-2409.09556","url":null,"abstract":"We demonstrate the use of [2-($textit{9H}$-carbazol-9-yl)ethyl]phosphonic\u0000acid (2PACz) and\u0000[2-(3,6-di-$textit{tert}$-butyl-$textit{9H}$-carbazol-9-yl)ethyl]phosphonic\u0000acid (t-Bu-2PACz) as anode modification layers in metal-halide perovskite\u0000quantum dot light-emitting diodes (QLEDs). Compared to conventional QLED\u0000structures with PEDOT:PSS (poly(3,4-ethylenedioxythiophene) polystyrene\u0000sulfonate)/PVK (poly(9-vinylcarbazole)) hole-transport layers, QLEDs made with\u0000phosphonic acid (PA)-modified indium tin oxide (ITO) anodes show an over 7-fold\u0000increase in brightness, achieving a brightness of 373,000 cd m$^{-2}$, one of\u0000the highest brightnesses reported to date for colloidal perovskite QLEDs.\u0000Importantly, the onset of efficiency roll-off, or efficiency droop, occurs at\u0000~1000-fold higher current density for QLEDs made with PA-modified anodes\u0000compared to control QLEDs made with conventional PEDOT:PSS/PVK hole transport\u0000layers, allowing the devices to sustain significantly higher levels of external\u0000quantum efficiency at a brightness of >10$^{5}$ cd m$^{-2}$. Steady-state and\u0000time-resolved photoluminescence measurements indicate these improvements are\u0000due to a combination of multiple factors, including reducing quenching of\u0000photoluminescence at the PEDOT:PSS interface and reducing photoluminescence\u0000efficiency loss at high levels of current density.","PeriodicalId":501137,"journal":{"name":"arXiv - PHYS - Mesoscale and Nanoscale Physics","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142253606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Theory of phonon angular momentum transport across smooth interfaces between crystals 晶体间光滑界面的声子角动量传输理论

arXiv - PHYS - Mesoscale and Nanoscale Physics Pub Date : 2024-09-13 DOI: arxiv-2409.08874

Yuta Suzuki, Shuntaro Sumita, Yusuke Kato

引用次数: 0