Physical Review Applied最新文献

{"title":"Evolution of zero-field skyrmionic states in exchange-coupled composite multilayer nanodots","authors":"Alexander Kang-Jun Toh, McCoy W. Lim, T.S. Suraj, Xiaoye Chen, Hang Khume Tan, Royston Lim, Xuan Min Cheng, Nelson Lim, Sherry Yap, Durgesh Kumar, S.N. Piramanayagam, Pin Ho, Anjan Soumyanarayanan","doi":"10.1103/physrevapplied.22.024036","DOIUrl":"https://doi.org/10.1103/physrevapplied.22.024036","url":null,"abstract":"Ambient magnetic skyrmions stabilized in multilayer nanostructures are of immense interest due to their relevance to magnetic tunnel junction (MTJ) devices for memory and unconventional computing applications. However, existing skyrmionic nanostructures built using conventional metallic or oxide multilayer nanodots are unable to concurrently fulfill the requirements of nanoscale skyrmion stability and all-electrical readout and manipulation. Here, we develop a few-repeat hybrid multilayer platform consisting of metallic <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mo stretchy=\"false\">[</mo><mi>Pt</mi><mo>/</mo><mrow><mi>Co</mi><mi mathvariant=\"normal\">B</mi></mrow><mo>/</mo><mi>Ir</mi><msub><mo stretchy=\"false\">]</mo><mn>3</mn></msub></math> and oxide [<math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>Pt</mi><mo>/</mo><mrow><mi>Co</mi><mi mathvariant=\"normal\">B</mi></mrow><mo>/</mo><mrow><mi>Mg</mi><mi mathvariant=\"normal\">O</mi></mrow></math>] components that are coupled to evolve together as a single, composite stack. Zero-field (ZF) skyrmions with sizes as small as 50 nm are stabilized in the hybrid multilayer nanodots, which are smoothly modulated by up to <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mn>2</mn><mo>×</mo></math> by varying <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>Co</mi><mi mathvariant=\"normal\">B</mi></mrow></math> thickness and dot sizes. Meanwhile, skyrmion multiplets are also stabilized by small bias fields. Crucially, we observe higher-order “target” skyrmions with varying magnetization rotations in moderately sized, low-anisotropy nanodots. These results provide a viable route to realize robust skyrmionic MTJs and alternative possibilities for multistate skyrmionic device concepts.","PeriodicalId":20109,"journal":{"name":"Physical Review Applied","volume":"29 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949302","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strong coherent ion-electron coupling using a wire data bus","authors":"Baiyi Yu, Ralf Betzholz, Jianming Cai","doi":"10.1103/physrevapplied.22.024032","DOIUrl":"https://doi.org/10.1103/physrevapplied.22.024032","url":null,"abstract":"Ion-ion coupling over long distances represents a highly useful resource for quantum technologies, for example, to sympathetically cool or interconnect qubits in ion-based quantum computing architectures. In this respect, the recently demonstrated wire-mediated ion-ion coupling stands due to the simplification of its trap layout and its prospects for deterministic entanglement. However, the strength of such coherent ion-wire-ion coupling is typically weak, hindering its practical utilization. Here, we propose a wire-mediated scheme for coherent ion-electron coupling. The scheme not only enables the sympathetic cooling of electrons via advanced ion-cooling techniques, but also allows promotion of the effective ion-ion coupling strength by orders of magnitudes via electron mediation. Our work thus paves a way toward quantum information processing in ion-electron hybrid quantum systems.","PeriodicalId":20109,"journal":{"name":"Physical Review Applied","volume":"39 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aluminum nuclear-demagnetization refrigerator for powerful continuous cooling","authors":"Matthias Raba, Sébastien Triqueneaux, James Butterworth, David Schmoranzer, Emilio Barria, Jérôme Debray, Guillaume Donnier-Valentin, Thibaut Gandit, Anne Gerardin, Johannes Goupy, Olivier Tissot, Eddy Collin, Andrew Fefferman","doi":"10.1103/physrevapplied.22.024027","DOIUrl":"https://doi.org/10.1103/physrevapplied.22.024027","url":null,"abstract":"Many laboratories routinely cool samples to 10 mK, but relatively few can cool condensed matter below 1 mK. Easy access to the microkelvin range would prove highly desirable in fields such as quantum sensors and quantum materials. Such temperatures are achieved with adiabatic nuclear demagnetization. Existing nuclear-demagnetization refrigerators (NDRs) are “single-shot,” and the recycling time is incompatible with some submillikelvin experiments. Furthermore, a high cooling power is required to overcome the excess heat load of nanowatt order on NDRs precooled by cryogen-free dilution refrigerators. We report the performance of an aluminum NDR designed for powerful cooling when part of a dual-stage continuous NDR (CNDR). Its thermal resistance is minimized to maximize the cycling rate of the CNDR and consequently its cooling power. At the same time, its susceptibility to eddy current heating is minimized. A CNDR based on two of the aluminum NDRs presented here would achieve a cooling power of approximately 40 nW at 560 <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mtext fontfamily=\"times\">μ</mtext><mrow><mi mathvariant=\"normal\">K</mi></mrow></math> less than <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mn>6</mn></math> days after cooling from room temperature, with a small offset in electronic temperature that decreases as the time-dependent heat load decays.","PeriodicalId":20109,"journal":{"name":"Physical Review Applied","volume":"117 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mitigating variability in epitaxial-heterostructure-based spin-qubit devices by optimizing gate layout","authors":"Biel Martinez, Silvano de Franceschi, Yann-Michel Niquet","doi":"10.1103/physrevapplied.22.024030","DOIUrl":"https://doi.org/10.1103/physrevapplied.22.024030","url":null,"abstract":"The scalability of spin-qubit devices is conditioned by qubit-to-qubit variability. Disorder in the host materials indeed affects the wave functions of the confined carriers, which leads to variations in their charge and spin properties. Charge disorder in the amorphous oxides is particularly detrimental owing to its long-range influence. Here we analyze the effects of charge traps at the semiconductor-oxide interface, which are generally believed to play a dominant role in variability. We consider multiple random distributions of these interface traps and numerically calculate their impact on the chemical potentials, detuning, and tunnel coupling of two adjacent quantum dots in <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mrow><mi>Si</mi><mi>Ge</mi></mrow></math> heterostructure. Our results highlight the beneficial screening effect of the metal gates. The surface of the heterostructure shall, therefore, be covered as much as possible by the gates in order to limit variability. We propose an alternative layout with tip-shaped gates that maximizes the coverage of the semiconductor-oxide interface and outperforms the usual planar layout in some regimes. This highlights the importance of design in the management of device-to-device variability.","PeriodicalId":20109,"journal":{"name":"Physical Review Applied","volume":"14 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Symmetry-based quantum circuit mapping","authors":"Di Yu, Kun Fang","doi":"10.1103/physrevapplied.22.024029","DOIUrl":"https://doi.org/10.1103/physrevapplied.22.024029","url":null,"abstract":"Quantum circuit mapping is a crucial process in the quantum circuit compilation pipeline, facilitating the transformation of a logical quantum circuit into a list of instructions directly executable on a target quantum system. Recent research has introduced a postcompilation step known as remapping, which seeks to reconfigure the initial circuit mapping to mitigate quantum circuit errors arising from system variability. As quantum processors continue to scale in size, the efficiency of quantum circuit mapping and the overall compilation process has become of paramount importance. In this work, we introduce a quantum circuit remapping algorithm that leverages the intrinsic symmetries in quantum processors, making it well suited for large-scale quantum systems. This algorithm identifies all topologically equivalent circuit mappings by constraining the search space using symmetries and accelerates the scoring of each mapping using vector computation. Notably, this symmetry-based-circuit-remapping algorithm exhibits linear scaling with the number of qubits in the target quantum hardware and is proven to be optimal in terms of its time complexity. Moreover, we conduct a comparative analysis against existing methods in the literature, demonstrating the superior performance of our symmetry-based method on state-of-the-art quantum hardware architectures and highlighting the practical utility of our algorithm, particularly for large-scale quantum computing.","PeriodicalId":20109,"journal":{"name":"Physical Review Applied","volume":"3 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Kinetic inductance parametric converter","authors":"M. Khalifa, P. Feldmann, J. Salfi","doi":"10.1103/physrevapplied.22.024025","DOIUrl":"https://doi.org/10.1103/physrevapplied.22.024025","url":null,"abstract":"Parametric converters are parametric amplifiers that mix two spatially separate nondegenerate modes and are commonly used for amplifying and squeezing microwave signals in quantum computing and sensing. In Josephson parametric converters, the strong localized nonlinearity of the Josephson junction limits the amplification and squeezing, as well as the dynamic range, in current devices. In contrast, a weak distributed nonlinearity can provide higher gain and dynamic range, when implemented as a kinetic inductance (KI) nanowire of a dirty superconductor, and has additional benefits such as resilience to magnetic field, higher-temperature operation, and simplified fabrication. Here, we propose, demonstrate, and analyze the performance of a KI parametric converter that relies on the weak distributed nonlinearity of a Nb-Ti-N KI nanowire. The device utilizes three-wave mixing induced by a dc current bias. We demonstrate its operation as a nondegenerate parametric amplifier with high phase-sensitive gain, reaching two-mode amplification and deamplification of approximately 30 dB for two resonances separated by 0.8 GHz, in excellent agreement with our theory of the device. We observe a dynamic range of <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mo>−</mo><mn>108</mn></math> dBm at 30 dB gain. Our device can significantly broaden applications of quantum-limited signal processing devices including phase-preserving amplification and two-mode squeezing.","PeriodicalId":20109,"journal":{"name":"Physical Review Applied","volume":"22 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nanocryotron ripple counter integrated with a superconducting nanowire single-photon detector for megapixel arrays","authors":"Matteo Castellani, Owen Medeiros, Reed A. Foster, Alessandro Buzzi, Marco Colangelo, Joshua C. Bienfang, Alessandro Restelli, Karl K. Berggren","doi":"10.1103/physrevapplied.22.024020","DOIUrl":"https://doi.org/10.1103/physrevapplied.22.024020","url":null,"abstract":"Decreasing the number of cables that bring heat into the cryostat is a critical issue for all cryoelectronic devices. In particular, arrays of superconducting nanowire single-photon detectors (SNSPDs) could require more than <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mn>10</mn><mn>6</mn></msup></math> readout lines. Performing signal-processing operations at low temperatures could be a solution. Nanocryotrons, superconducting nanowire three-terminal devices, are good candidates for integrating sensing and electronics on the same technological platform as SNSPDs in photon-counting applications. In this work, we demonstrate that it is possible to read out, process, encode, and store the output of SNSPDs using exclusively superconducting nanowires patterned on niobium nitride thin films. In particular, we present the design and development of a nanocryotron ripple counter that detects input voltage spikes and converts the number of pulses to an <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>N</mi></math>-digit value. The counting base can be tuned from 2 to higher values, enabling higher maximum counts without enlarging the circuit. As a proof of principle, we first experimentally demonstrate the building block of the counter, an integer-<math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>N</mi></math> frequency divider with <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mi>N</mi></math> ranging from 2 to 5. Then, we demonstrate photon-counting operations at 405 nm and 1550 nm by coupling an SNSPD with a two-digit nanocryotron counter partially integrated on chip. The two-digit counter can operate in either base 2 or base 3, with a bit-error rate lower than <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><mn>2</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>4</mn></mrow></msup></math> and a count rate of <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mn>10</mn><mn>7</mn></msup><mspace width=\"0.2em\"></mspace><msup><mrow><mrow><mi mathvariant=\"normal\">s</mi></mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math>. We simulate circuit architectures for integrated readout of the counter state and we evaluate the capabilities of reading out an SNSPD megapixel array that would collect up to <math display=\"inline\" overflow=\"scroll\" xmlns=\"http://www.w3.org/1998/Math/MathML\"><msup><mn>10</mn><mn>12</mn></msup></math> counts per second. The results of this work, combined with our recent publications on a nanocryotron shift register and logic gates, pave the way for the development of nanocryotron processors, from which multiple superconducting platforms may benefit.","PeriodicalId":20109,"journal":{"name":"Physical Review Applied","volume":"28 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnetic microelastography for evaluation of ultrasound-induced softening of pancreatic cancer spheroids","authors":"G. Laloy-Borgna, L. Vovard, A. Rohfritsch, L. Wang, J. Ngo, M. Perier, A. Drainville, F. Prat, M. Lafond, C. Lafon, S. Catheline","doi":"10.1103/physrevapplied.22.024024","DOIUrl":"https://doi.org/10.1103/physrevapplied.22.024024","url":null,"abstract":"Pancreatic ductal adenocarcinoma is a devastating disease with very low survival rates 5 years after diagnosis. The main reason for this dismal prognosis is the thick stroma which both protects tumor cells from drug penetration and supports tumor development. Ultrasound inertial cavitation is a promising treatment with potential for stromal disruption, enhancing tumor cells’ sensitivity to chemical agents and biomodulators. Our goal was to develop a dedicated microelastography setup allowing us to measure the elasticity of <i>in vitro</i> tumor models called spheroids. In a second step, the impact of cavitation treatment on their mechanical properties was assessed. A transcranial magnetic stimulation clinical device was used to induce shear waves in the spheroids containing magnetic nanoparticles. Using an inverted optical microscope, particle imaging velocimetry, and noise correlation algorithms, the shear wave velocity, indicative of the medium’s elasticity, could be measured. Shear waves generated by the magnetic pulse inside the spheroids were detected and their velocity was measured using noise correlation elastography. This allowed the estimation of the spheroids’ elasticity. Cavitation treatment softened them significantly, and the impact of the exposure conditions and the spheroids’ composition have been studied. In the future, such a method could be used to monitor cavitation treatments. In addition, since it is now well established that mechanical constraints and elasticity play an important role in tumor growth, it is of great interest to measure the elasticity of tumor models to better understand the mechanisms of tumor growth.","PeriodicalId":20109,"journal":{"name":"Physical Review Applied","volume":"74 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine-learning optimal control pulses in an optical quantum memory experiment","authors":"Elizabeth Robertson, Luisa Esguerra, Leon Meßner, Guillermo Gallego, Janik Wolters","doi":"10.1103/physrevapplied.22.024026","DOIUrl":"https://doi.org/10.1103/physrevapplied.22.024026","url":null,"abstract":"Efficient optical quantum memories are a milestone required for several quantum technologies, including repeater-based quantum key distribution and on-demand multiphoton generation. We present an efficiency optimization of an optical electromagnetically induced transparency (EIT) memory experiment in a warm cesium vapor using a genetic algorithm and analyze the resulting wave forms. The control pulse is represented either as a Gaussian or free-form pulse and the results from the optimization are compared. We see an improvement factor of 3(7)% when using optimized free-form pulses. By limiting the allowed pulse energy in a solution, we show an energy-based optimization giving a 30% reduction in energy, with minimal efficiency loss.","PeriodicalId":20109,"journal":{"name":"Physical Review Applied","volume":"75 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Power-in-bucket enhancement in tiled-aperture coherent beam combining through inducing spatial chirp","authors":"Wenhai Liang, Shuman Du, Renjing Chen, Chengru Wu, Xiong Shen, Peng Wang, Jun Liu, Ruxin Li","doi":"10.1103/physrevapplied.22.024018","DOIUrl":"https://doi.org/10.1103/physrevapplied.22.024018","url":null,"abstract":"Spatial gaps between sub-beams in high-peak-power lasers with tiled-aperture-based coherent beam combining (TACBC) give rise to relatively strong sidelobes and impair the power in bucket (PIB) at far field<b>.</b> To address the aforementioned issue, spatial chirp is employed in this paper to fill the gaps and further enhance PIB. With two sub-beams, both simulations and experiments indicate that spatial chirp can boost PIB by 1.8 times at a gap-beam width ratio of 0.2. The same enhancement is observed in simulations even when four sub-beams are considered. To put it briefly, the spatial-chirp-assisted TACBC approach holds the potential in boosting focal intensity during constructing tens to hundreds of petawatt (PW) lasers.","PeriodicalId":20109,"journal":{"name":"Physical Review Applied","volume":"6 1","pages":""},"PeriodicalIF":4.6,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141949314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}