{"title":"First Principles Investigation of Gas Adsorption on Bilayer Transition Metal Dichalcogenides for Sensing Toxic Gases","authors":"Jemal Yimer Damte, Hassan Ataalite","doi":"arxiv-2409.06500","DOIUrl":"https://doi.org/arxiv-2409.06500","url":null,"abstract":"Transition metal dichalcogenides have shown great promise in the field of gas\u0000sensing due to their high catalytic activity and unique electronic properties.\u0000They can effectively interact with various gas molecules, making them suitable\u0000materials for high performance gas sensors. In this work, we have studied the\u0000sensing properties of nitrogen containing gases on different heterostructures\u0000using density functional studies. The result shows that NH3 and NOx exhibit\u0000weak electronic interactions with MoS/WTe and MoTe/WS heterostructures and\u0000strong electronic interactions are observed between NH3 and NOx molecules with\u0000MoS/IrO and MoS/TiO heterostructures.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177769","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}
Mark P. Zic, Linda Ye, Maya H. Martinez, Ian R. Fisher
{"title":"Realization of giant elastocaloric cooling at cryogenic temperatures in TmVO$_4$ via a strain load/unload technique","authors":"Mark P. Zic, Linda Ye, Maya H. Martinez, Ian R. Fisher","doi":"arxiv-2409.06909","DOIUrl":"https://doi.org/arxiv-2409.06909","url":null,"abstract":"The adiabatic elastocaloric effect relates changes in the strain that a\u0000material experiences to resulting changes in its temperature. While\u0000elastocaloric materials have been utilized for cooling in room temperature\u0000applications, the use of such materials for cryogenic cooling remains\u0000relatively unexplored. Here, we use a strain load/unload technique at low\u0000temperatures, similar to those employed at room-temperature, to demonstrate a\u0000large cooling effect in TmVO$_4$. For strain changes of $1.8 cdot 10^{-3}$,\u0000the inferred cooling reaches approximately 50% of the material's starting\u0000temperature at 5 K, justifying the moniker \"giant\". Beyond establishing the\u0000suitability of this class of material for cryogenic elastocaloric cooling,\u0000these measurements also provide additional insight to the entropy landscape in\u0000the material as a function of strain and temperature, including the behavior\u0000proximate to the quadrupolar phase transition.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177768","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}
David A. van Nijen, Paul Procel, René A. C. M. M. van Swaaij, Miro Zeman, Olindo Isabella, Patrizio Manganiello
{"title":"The nature of silicon PN junction impedance at high frequency","authors":"David A. van Nijen, Paul Procel, René A. C. M. M. van Swaaij, Miro Zeman, Olindo Isabella, Patrizio Manganiello","doi":"arxiv-2409.06749","DOIUrl":"https://doi.org/arxiv-2409.06749","url":null,"abstract":"A thorough understanding of the small-signal response of solar cells can\u0000reveal intrinsic device characteristics and pave the way for innovations. This\u0000study investigates the impedance of crystalline silicon PN junction devices\u0000using TCAD simulations, focusing on the impact of frequency, bias voltage, and\u0000the presence of a low-high (LH) junction. It is shown that the PN junction\u0000exhibits a fixed $RC$-loop behavior at low frequencies, but undergoes\u0000relaxation in both resistance $R_j$ and capacitance $C_j$ as frequency\u0000increases. Moreover, it is revealed that the addition of a LH junction impacts\u0000the impedance by altering $R_j$, $C_j$, and the series resistance $R_s$.\u0000Contrary to conventional modeling approaches, which often include an additional\u0000$RC$-loop to represent the LH junction, this study suggests that such a\u0000representation does not represent the underlying physics, particularly the\u0000frequency-dependent behavior of $R_j$ and $C_j$.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"64 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177766","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}
Albert Salmi, Miloslav Capek, Lukas Jelinek, Anu Lehtovuori, Ville Viikari
{"title":"Optimization of Embedded Element Patterns of Reactively Loaded Antenna Arrays","authors":"Albert Salmi, Miloslav Capek, Lukas Jelinek, Anu Lehtovuori, Ville Viikari","doi":"arxiv-2409.06291","DOIUrl":"https://doi.org/arxiv-2409.06291","url":null,"abstract":"This paper introduces a framework for synthesizing reactively loaded antennas\u0000and antenna arrays. The framework comprises two main components: computing the\u0000fundamental bound using the semi-definite relaxation and finding a realizable\u0000solution via optimization on a Riemannian manifold. The embedded element\u0000patterns are subject to the optimization with two distinct goals under study:\u0000focusing the radiation in a single direction or synthesizing patterns with\u0000desired shapes. The reactive terminations of passive antenna elements serve as\u0000optimization variables. We demonstrate the framework using a connected\u0000bowtie-slot antenna and antenna array with both beam-focusing and beam-shaping\u0000targets. The tests show that the optimization on the Riemannian manifold yields\u0000superior results compared to existing methods, such as the genetic algorithm.\u0000This is particularly evident in the most complex and extensive problem, which\u0000requires the synthesis of shaped embedded element patterns for a sparse\u0000reactively loaded antenna array with a limited field of view.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177770","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}
{"title":"Mimicking synaptic plasticity with wedged Pt/Co/Pt spin-orbit torque device","authors":"Shiwei Chen, Mishra Rahul, Huanjian Chen, Hyunsoo Yang, Xuepeng Qiu","doi":"arxiv-2409.06286","DOIUrl":"https://doi.org/arxiv-2409.06286","url":null,"abstract":"We fabricated a wedge-shaped Pt/Co/Pt device with perpendicular magnetic\u0000anisotropy and manifested that the Co magnetization can be solely switched by\u0000spin-orbit torque without any magnetic field. Similar to the synaptic weight,\u0000we observed that the state of Co magnetization (presented by the anomalous Hall\u0000resistance RH) of the wedged Pt/Co/Pt device can be tuned continuously with a\u0000large number of nonvolatile levels by applied pulse currents. Furthermore, we\u0000studied the synaptic plasticity of the wedged Pt/Co/Pt device, including the\u0000excitatory postsynaptic potentials or inhibitory postsynaptic potentials and\u0000spiking-time-dependent plasticity. The work elucidates the promise of the\u0000wedged Pt/Co/Pt device as a candidate for a new type of artificial synaptic\u0000device that is induced by a spin current and paves a substantial pathway toward\u0000the combination of spintronics and synaptic devices.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142223490","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}
Bernard Dieny, Sanjeev Aggarwal, Vinayak Bharat Naik, Sebastien Couet, Thomas Coughlin, Shunsuke Fukami, Kevin Garello, Jack Guedj, Jean Anne C. Incorvia, Laurent Lebrun, Kyung-Jin Lee, Daniele Leonelli, Yonghwan Noh, Siamak Salimy, Steven Soss, Luc Thomas, Weigang Wang, Daniel Worledge
{"title":"Impact of external magnetic fields on STT-MRAM","authors":"Bernard Dieny, Sanjeev Aggarwal, Vinayak Bharat Naik, Sebastien Couet, Thomas Coughlin, Shunsuke Fukami, Kevin Garello, Jack Guedj, Jean Anne C. Incorvia, Laurent Lebrun, Kyung-Jin Lee, Daniele Leonelli, Yonghwan Noh, Siamak Salimy, Steven Soss, Luc Thomas, Weigang Wang, Daniel Worledge","doi":"arxiv-2409.05584","DOIUrl":"https://doi.org/arxiv-2409.05584","url":null,"abstract":"This application note discusses the working principle of spin-transfer torque\u0000magnetoresistive random access memory (STT-MRAM) and the impact that magnetic\u0000fields can have on STT-MRAM operation. Sources of magnetic field and typical\u0000magnitudes of magnetic fields are given. Based on the magnitude of commonly\u0000encountered external magnetic fields, we show below that magnetic immunity of\u0000STT-MRAM is sufficient for most uses once the chip is mounted on a printed\u0000circuit board (PCB) or inserted in its working environment. This statement is\u0000supported by the experience acquired during 60 years of use of magnetic hard\u0000disk drives (HDD) including 20 years of HDD with readers comprising magnetic\u0000tunnel junctions, 20+ years of use of magnetic field sensors as position\u0000encoders in automotive industry and 15+ years of use of MRAM. Mainly during\u0000chip handling does caution need to be exercised to avoid exposing the chip to\u0000excessively high magnetic fields.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177774","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}
Kai Wen, Huijin Chen, Xu Yan, Zejian Ren, Chengdong He, Elnur Hajiyev, Preston Tsz Fung Wong, Gyu-Boong Jo
{"title":"Apparatus for producing single strontium atoms in an optical tweezer array","authors":"Kai Wen, Huijin Chen, Xu Yan, Zejian Ren, Chengdong He, Elnur Hajiyev, Preston Tsz Fung Wong, Gyu-Boong Jo","doi":"arxiv-2409.05361","DOIUrl":"https://doi.org/arxiv-2409.05361","url":null,"abstract":"We outline an experimental setup for efficiently preparing a tweezer array of\u0000$^{88}$Sr atoms. Our setup uses permanent magnets to maintain a steady-state\u0000two-dimensional magneto-optical trap (MOT) which results in a loading rate of\u0000up to $10^{8}$ s$^{-1}$ at 5 mK for the three-dimensional blue MOT. This\u0000enables us to trap $2times10^{6}$ $^{88}$Sr atoms at 2 $mu$K in a narrow-line\u0000red MOT with the $^{1}$S$_{0}$ $rightarrow$ $^{3}$P$_{1}$ intercombination\u0000transition at 689 nm. With the Sisyphus cooling and pairwise loss processes,\u0000single atoms are trapped and imaged in 813 nm optical tweezers, exhibiting a\u0000lifetime of 2.5 minutes. We further investigate the survival fraction of a\u0000single atom in the tweezers and characterize the optical tweezer array using a\u0000release and recapture technique. Our platform paves the way for potential\u0000applications in atomic clocks, precision measurements, and quantum simulations.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"156 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177777","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}
{"title":"Energy Shift with Coupling (ESC): a new quench protection method","authors":"Emmanuele Ravaioli, Arjan Verweij, Mariusz Wozniak","doi":"arxiv-2409.05446","DOIUrl":"https://doi.org/arxiv-2409.05446","url":null,"abstract":"Quench protection of full-size high-field accelerator magnets poses\u0000significant challenges. Maintaining the hot-spot temperature and peak\u0000voltage-to-ground within acceptable limits requires a protection system that\u0000quickly transitions most of the coil turns to the normal state. Existing magnet\u0000protection technologies, such as quench protection heaters or the Coupling Loss\u0000Induced Quench system (CLIQ), have been successfully applied. However, they\u0000both present shortcomings since they require either thin insulation between the\u0000heaters and the magnet conductor or direct electrical connections to the magnet\u0000coil. A novel quench protection method, Energy Shift with Coupling (ESC), is\u0000presented which can achieve excellent quench protection performance without the\u0000above-mentioned drawbacks. ESC relies on normal-conducting auxiliary coils\u0000strongly magnetically coupled with the magnet coils to protect. Upon quench\u0000detection capacitive units connected across such coils introduce a high current\u0000change in the auxiliary coils causing a rapid shift of magnet stored energy\u0000from the magnet coils to the auxiliary coils. This has three beneficial\u0000effects: sudden reduction of ohmic loss in the normal zone of the magnet\u0000conductor, introduction of high transient losses in the magnet conductor, thus\u0000causing a quick transition to the normal state, and extraction of a part of the\u0000magnet stored energy to the auxiliary coils. The applicability of the ESC\u0000concept on an existing magnet design is analyzed with electromagnetic and\u0000thermal transient simulations performed with the STEAM-LEDET program. The\u0000advantages and disadvantages of ESC are discussed and compared to other\u0000conventional quench protection methods. Simulation results show that ESC can be\u0000applied to protect full-scale magnets with reasonable requirements in terms of\u0000size and location of the auxiliary coils and of capacitive unit parameters.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177775","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}
Mariusz Mrózek, Adam Filipkowski, Wojciech Gawlik, Ryszard Buczyński, Adam M. Wojciechowski, Mariusz Klimczak
{"title":"Localization of macroscopic sources of magnetic field using optical fibers doped with NV-rich sub-micron diamonds and zero-field resonance","authors":"Mariusz Mrózek, Adam Filipkowski, Wojciech Gawlik, Ryszard Buczyński, Adam M. Wojciechowski, Mariusz Klimczak","doi":"arxiv-2409.05452","DOIUrl":"https://doi.org/arxiv-2409.05452","url":null,"abstract":"We employ an optical fiber doped with randomly oriented fluorescent\u0000sub-micron diamonds and the novel zero-field resonance protocol to collect\u0000information on the localization and orientation of a magnetic-field source and\u0000its distribution. Many previous demonstrations of diamond-based magnetic field\u0000sensing achieved ultrahigh sensitivities down to the fT range warranted by\u0000manipulating spin states of the diamond nitrogen vacancy (NV) centers with\u0000externally applied radio or microwaves. The application of such oscillating\u0000fields is problematic in distributed magnetic-field measurements and may be\u0000incompatible with specific targets. Instead of relying on these approaches, we\u0000leveraged cross-relaxations of particular spin-state populations of the NV\u0000center under a magnetic field, thus observing zero-field resonances and making\u0000external radio frequency fields redundant. Combined with an optical fiber\u0000sensitive to the magnetic field along its entire length, remote sensing was\u0000realized that returned information on the spatial field distribution without\u0000using any moving mechanical elements in the detection system. Variation of the\u0000spatial parameters of the investigated field was achieved simply by controlling\u0000the current in a pair of induction coils easily integrable with optical fibers\u0000without limiting the fiber-specific functionality of the optical readout taking\u0000place at a fixed location at the optical fiber output. Lifting of the\u0000requirements related to the mechanical scanning of the fiber, the application\u0000of external fields, and the orientation of the NV centers against the measured\u0000field mark a very practical step forward in optically driven magnetic field\u0000sensing, not easily achievable with earlier implementations.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"79 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177776","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}
Saravanan Lakshmanan, Cristian Romanque, Mario Mery, Manivel Raja Muthuvel, Nanhe Kumar Gupta, Carlos Garcia
{"title":"Effects of Interfacial Oxygen Diffusion on the Magnetic Properties and Thermal Stability of Pd/CoFeB/Pd/Ta Heterostructure","authors":"Saravanan Lakshmanan, Cristian Romanque, Mario Mery, Manivel Raja Muthuvel, Nanhe Kumar Gupta, Carlos Garcia","doi":"arxiv-2409.05783","DOIUrl":"https://doi.org/arxiv-2409.05783","url":null,"abstract":"We investigated the effects of annealing temperatures (TA) on a Pd (5\u0000nm)/CoFeB (10 nm)/Pd (3 nm)/Ta (10 nm) multilayer structure. The as-deposited\u0000sample showed an amorphous state with in-plane uniaxial magnetic anisotropy\u0000(UMA), resulting in low coercivity and moderate damping constant ({alpha})\u0000values. Increasing TA led to crystallization, forming bcc-CoFe (110) crystals,\u0000which increased in-plane coercivity and introduced isotropic magnetic\u0000anisotropy, slightly reducing the {alpha}. The two-fold UMA persists up to 600\u0000C, and the thermal stability of the in-plane magnetic anisotropy remains intact\u0000even TA = 700 C. The TA significantly influenced the magnetic properties such\u0000as in-plane saturation magnetization (Ms//), in-plane and out-of-plane\u0000coercivities, and in-plane effective magnetic anisotropy energy density (Keff).\u0000Above 600 C, Keff decreased, indicating a transition towards uniaxial\u0000perpendicular magnetic anisotropy. Interfacial oxidation and diffusion from the\u0000Ta capping layer to the Pd/CoFeB/Pd interfaces were observed, influencing\u0000chemical bonding states. Annealing at 700 C, reduced oxygen within TaOx through\u0000a redox reaction involving Ta crystallization, forming TaB, PdO, and BOx\u0000states. Ferromagnetic resonance spectra analysis indicated variations in\u0000resonance field (Hr) due to local chemical environments. The {alpha}\u0000reduction, reaching a minimum at 300 C annealing, was attributed to reduced\u0000structural disorder from inhomogeneities. Tailoring magnetic anisotropy and\u0000spin dynamic properties in Pd/CoFeB/Pd/Ta structures through TA-controlled\u0000oxygen diffusion/oxidation highlights their potential for SOT, DMI, and\u0000magnetic skyrmion-based spintronic devices.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"108 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142177780","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}