Advanced quantum technologies最新文献

{"title":"Hardware-Efficient Quantum Random Access Memory Design with a Native Gate Set on Superconducting Platforms","authors":"Yun-Jie Wang,&nbsp;Sheng Zhang,&nbsp;Tai-Ping Sun,&nbsp;Ze-An Zhao,&nbsp;Xiao-Fan Xu,&nbsp;Xi-Ning Zhuang,&nbsp;Huan-Yu Liu,&nbsp;Cheng Xue,&nbsp;Peng Duan,&nbsp;Yu-Chun Wu,&nbsp;Zhao-Yun Chen,&nbsp;Guo-Ping Guo","doi":"10.1002/qute.202400519","DOIUrl":"https://doi.org/10.1002/qute.202400519","url":null,"abstract":"<p>Quantum Random Access Memory (QRAM) is a critical component for enabling data queries in superposition, which is the cornerstone of quantum algorithms. Among various QRAM architectures, the bucket-brigade model stands out due to its noise resilience. This study presents a hardware-efficient native gate set <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>{</mo>\u0000 <mi>iSCZ</mi>\u0000 <mo>,</mo>\u0000 <mi>C</mi>\u0000 <mo>−</mo>\u0000 <mi>iSCZ</mi>\u0000 <mo>,</mo>\u0000 <msup>\u0000 <mi>S</mi>\u0000 <mo>†</mo>\u0000 </msup>\u0000 <mo>}</mo>\u0000 </mrow>\u0000 <annotation>$lbrace textsf {iSCZ}, textsf {C-iSCZ}, textsf {S}^{dagger }rbrace$</annotation>\u0000 </semantics></math> for implementing bucket-brigade QRAM on superconducting platforms. The experimental feasibility of the proposed gate set is demonstrated, showing high fidelity and reduced complexity. By leveraging the complementary control property in QRAM, the approach directly substitutes the conventional <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mo>{</mo>\u0000 <mi>SWAP</mi>\u0000 <mo>,</mo>\u0000 <mi>CSWAP</mi>\u0000 <mo>}</mo>\u0000 </mrow>\u0000 <annotation>$lbrace textsf {SWAP}, textsf {CSWAP} rbrace$</annotation>\u0000 </semantics></math> gates with the new gate set, eliminating decomposition overhead and significantly reducing circuit depth and gate count.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 5","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944939","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":"Heteroepitaxial (111) Diamond Quantum Sensors with Preferentially Aligned Nitrogen-Vacancy Centers for an Electric Vehicle Battery Monitor","authors":"Kenichi Kajiyama,&nbsp;Moriyoshi Haruyama,&nbsp;Yuji Hatano,&nbsp;Hiromitsu Kato,&nbsp;Masahiko Ogura,&nbsp;Toshiharu Makino,&nbsp;Hitoshi Noguchi,&nbsp;Takeharu Sekiguchi,&nbsp;Takayuki Iwasaki,&nbsp;Mutsuko Hatano","doi":"10.1002/qute.202400400","DOIUrl":"https://doi.org/10.1002/qute.202400400","url":null,"abstract":"<p>A platform for heteroepitaxial (111) chemical vapor deposition (CVD) diamond quantum sensors with preferentially aligned nitrogen vacancy (NV) centers on a large substrate is developed, and its operation as an electric vehicle (EV) battery monitor is demonstrated. A self-standing heteroepitaxial CVD diamond film with a (111) orientation and a thickness of 150 µm is grown on a non-diamond substrate and subsequently separated from it. The high uniformity and crystallinity of the (111)-oriented diamond is confirmed. A 150-µm thick NV-diamond layer is then deposited on the heteroepitaxial diamond. The <i>T</i>₂ value measured by confocal microscopy is 20 µs, which corresponds to substitutional nitrogen defect concentration of 8 ppm. The nitrogen-vacancy concentration and <i>T</i>₂^* are estimated to be 0.05 ppm and 0.05 µs by continuous wave optically detected magnetic resonance (CW-ODMR) spectroscopy in a fiber-top sensor configuration. In a gradiometer, where two sensors are placed on both sides of the busbar, the noise floor is 17 nT/Hz^0.5 in the frequency range of 10–40 Hz without magnetic shielding. The Allan deviation of the magnetic field noise in the laboratory is below 0.3 µT, which corresponds to a busbar current of 10 mA, in the accumulation time range of 10 ms to 100 s.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 4","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202400400","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143793328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Joint Wire Cutting with Non-Maximally Entangled States","authors":"Marvin Bechtold,&nbsp;Johanna Barzen,&nbsp;Frank Leymann,&nbsp;Alexander Mandl,&nbsp;Felix Truger","doi":"10.1002/qute.202400555","DOIUrl":"https://doi.org/10.1002/qute.202400555","url":null,"abstract":"<p>Distributed quantum computing leverages multiple quantum devices collectively to perform computations exceeding each device's capabilities. A currently studied technique to enable this distributed approach is wire cutting, which decomposes a quantum circuit into smaller subcircuits by cutting connecting wires. These subcircuits can be executed on distributed devices, and their results are then classically combined to reconstruct the original computation's result. However, wire cutting requires additional circuit executions to preserve result accuracy, with their number growing exponentially with each cut. Thus, minimizing this sampling overhead is crucial for reducing execution time. Employing shared non-maximally entangled (NME) states between distributed devices reduces this overhead for single wire cuts, approaching ideal teleportation with maximally entangled states. Extending this approach to jointly cutting multiple wires using NME states remained unexplored. This study addresses this gap by investigating the use of NME states for joint wire cuts, aiming to reduce the sampling overhead further. The three main contributions include (i) determining the minimal sampling overhead for this scenario, (ii) analyzing the overhead when using composite NME states constructed from smaller NME states, and (iii) introducing a wire cutting technique that achieves the optimal sampling overhead with pure NME states, advancing toward wire cutting with arbitrary NME states.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 5","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202400555","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Front Cover: Enhanced Quantum Entanglement Detection of General Two Qubits Systems Based on Modified CNN-BiLSTM Model (Adv. Quantum Technol. 1/2025)","authors":"Qian Sun,&nbsp;Zhichuan Liao,&nbsp;Nan Jiang","doi":"10.1002/qute.202570001","DOIUrl":"https://doi.org/10.1002/qute.202570001","url":null,"abstract":"<p>As a fusion improvement algorithm for convolution neural networks and recurrent neural networks, CNN-BiLSTM demonstrates its powerful fitting ability and generalization ability for complex data. In article number 2400373, Nan Jiang and co-workers combine this algorithm with quantum entanglement classification problems, achieving perfect performance for nearly all 2-qubits quantum systems.\u0000\u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202570001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143114332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Issue Information (Adv. Quantum Technol. 1/2025)","authors":"","doi":"10.1002/qute.202570002","DOIUrl":"https://doi.org/10.1002/qute.202570002","url":null,"abstract":"","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 1","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202570002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143114144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantum Ghost Imaging by Sparse Spatial Mode Reconstruction","authors":"Fazilah Nothlawala,&nbsp;Chané Moodley,&nbsp;Neelan Gounden,&nbsp;Isaac Nape,&nbsp;Andrew Forbes","doi":"10.1002/qute.202400577","DOIUrl":"https://doi.org/10.1002/qute.202400577","url":null,"abstract":"<p>In a conventional quantum imaging experiment, the image of the object is retrieved directly with single photon camera technology, or computationally with a single-pixel detector and pixelated projective masks. In all these approaches, the resolution of the image is dictated by the pixel resolution of the detection devices. In this paper, the traditional spatial basis of pixels is replaced with spatial modes, exploiting their unique features to enhance image fidelity and resolution and improve reconstruction accuracy through modal sparsity. This approach can be used even when the modes are not orthogonal, demonstrating the principle with highly efficient phase-only approximations to the modal basis. By numerical simulation and experimental analysis, the advantages of this approach are illustrated, which include faster convergence to the object, with higher signals and fidelity, which are demonstrated with an order of magnitude less masks than conventional approaches for the same fidelity in outcome. Unlike the basis of pixels, the resolution of the image is not dictated by the resolution of the detectors, opening a path to high-resolution quantum imaging of complex objects.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 5","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202400577","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proposal for a Bose–Einstein Condensate Based Test of Born's Rule Using Light–Pulse Atom Interferometry","authors":"Simon Kanthak,&nbsp;Julia Pahl,&nbsp;Daniel Reiche,&nbsp;Markus Krutzik","doi":"10.1002/qute.202400436","DOIUrl":"https://doi.org/10.1002/qute.202400436","url":null,"abstract":"<p>Light-pulse atom interferometry with ultra-cold quantum gases is proposed and numerically benchmarked as a platform to test the modulo-square hypothesis of Born's rule. The interferometric protocol is based on a combination of double Bragg and single Raman diffraction to induce multipath interference in Bose–Einstein condensates (BECs) and block selected interferometer paths, respectively. In contrast to previous tests employing macroscopic material slits and blocking masks, optical diffraction lattices provide a high degree of control and avoid possible systematic errors like geometrical inaccuracies from manufacturing processes. In addition, sub-recoil expansion rates of delta-kick collimated BECs allow to prepare, distinguish and selectively address the external momentum states of the atoms. This further displays in close-to-unity diffraction fidelities favorable for both high-contrast interferometry and high extinction of the blocking masks. In return, non-linear phase shifts caused by repulsive atom-atom interactions need to be taken into account, which we fully reflect in our numerical simulations of the multipath interferometer. Assuming that the modulo-square rule holds, the impact of experimental uncertainties is examined in accordance with conventional BEC interferometer to provide an upper bound of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>5.7</mn>\u0000 <mo>×</mo>\u0000 <msup>\u0000 <mn>10</mn>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>3</mn>\u0000 </mrow>\u0000 </msup>\u0000 <mspace></mspace>\u0000 <mfenced>\u0000 <mn>1.8</mn>\u0000 <mo>×</mo>\u0000 <msup>\u0000 <mn>10</mn>\u0000 <mrow>\u0000 <mo>−</mo>\u0000 <mn>3</mn>\u0000 </mrow>\u0000 </msup>\u0000 </mfenced>\u0000 </mrow>\u0000 <annotation>$5.7times 10^{-3} left(1.8times 10^{-3}right)$</annotation>\u0000 </semantics></math> on the statistical deviation of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>100</mn>\u0000 <mspace></mspace>\u0000 <mfenced>\u0000 <mn>1000</mn>\u0000 </mfenced>\u0000 </mrow>\u0000 <annotation>$100 left(1000right)$</annotation>\u0000 </semantics></math> iterations for a hypothetical third-order interference term.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 6","pages":""},"PeriodicalIF":4.4,"publicationDate":"2025-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202400436","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144273309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect and Compensation of Polarization-Dependent Loss in Free-Space Reference Frame Independent Quantum Key Distribution","authors":"Kyongchun Lim,&nbsp;Byung-Seok Choi,&nbsp;Ju Hee Baek,&nbsp;Minchul Kim,&nbsp;Joong-Seon Choe,&nbsp;Kap-Joong Kim,&nbsp;Dong Churl Kim,&nbsp;Junsang Oh,&nbsp;Chun Ju Youn","doi":"10.1002/qute.202400492","DOIUrl":"https://doi.org/10.1002/qute.202400492","url":null,"abstract":"<p>Polarization-dependent loss (PDL) poses a critical challenge in implementing free-space quantum key distribution (QKD) systems. This study investigated the theoretical and experimental impact of PDL on polarization-encoded qubits and experimentally demonstrated a method to mitigate these effects. The proposed compensation method could effectively restore the integrity of polarization states, enhancing the robustness and security of QKD systems. Specifically, a secret key rate of 94.01% could be recovered with 5 dB PDL. This study contributes to advancing scalable and secure quantum communication technologies by addressing the critical issue of PDL in QKD systems.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 3","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/qute.202400492","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143622360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Remote Implementation of Particular Subsets of Operations in two Degrees of Freedom","authors":"Meiyu Wang,&nbsp;Jiashuai Cao,&nbsp;Bing Di","doi":"10.1002/qute.202400583","DOIUrl":"https://doi.org/10.1002/qute.202400583","url":null,"abstract":"<p>Hyperentanglement of photon systems is a fascinating resource in long-distance quantum information processing and communication for its improvement to the channel capacity. Remote implementation of quantum operation (RIO) using a hyperentangled state has attracted much attention for its critical role in many quantum applications. In this study, a protocol for the remote implementation of particular subsets of operations exploiting a pair of photons hyperentangled in their polarization and time-bin degrees of freedom (DOFs) is presented. The core of this scheme is to construct polarization and time-bin parity-check quantum nondemolition detectors (QNDs), which mainly rely on the effective cross-Kerr nonlinear interaction and X homodyne measurements. The efficiency of the scheme is calculated in terms of bits of transmission and consumption. Compared with the RIO using the polarization-spatial-mode hyperentangled state, the present scheme saves resources since there is no requirement for two paths for each photon. Further, given some applicable experimental parameters, the fidelity due to the effect of decoherence in the circuits is analyzed, and the result demonstrates a high fidelity in the presence of photon dissipation. Since the time-bin DOF is more robust over a channel, especially from space to earth, this RIO protocol presents a promising approach for building a global quantum-communication network.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 6","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144273220","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":"Efficient Satellite QKD Strategy Using High-Brightness Entangled Photon-Pair Source with Fixed-Intensity","authors":"Jin-Woo Kim,&nbsp;Suseong Lim,&nbsp;Heonoh Kim,&nbsp;June-Koo Kevin Rhee","doi":"10.1002/qute.202400489","DOIUrl":"https://doi.org/10.1002/qute.202400489","url":null,"abstract":"<p>A high-brightness entangled photon-pair (HBEPP) source is essential for long-reach entanglement-based quantum key distribution (QKD) such as in a satellite QKD system. An ultrabright source is a good candidate to overcome significant losses and to increase the sifted key rate, but the performance is critically limited due to the multi-photon effect that raises the error rate of the system. To accurately estimate system performance, this study first investigates an analytical model for calculating the measurement probabilities of HBEPP distribution through an asymmetric loss channel. Based on this model, this study proposes the use of a fixed-intensity HBEPP source for satellite QKD systems, assuming a polarization-independent channel and threshold detectors for measurement. This study confirms that fixing the mean photon number at <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mover>\u0000 <mi>μ</mi>\u0000 <mo>¯</mo>\u0000 </mover>\u0000 <mo>=</mo>\u0000 <mn>0.1</mn>\u0000 </mrow>\u0000 <annotation>$bar{mu }=0.1$</annotation>\u0000 </semantics></math> achieves a performance of <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <mn>99.7</mn>\u0000 <mo>%</mo>\u0000 </mrow>\u0000 <annotation>$99.7%$</annotation>\u0000 </semantics></math> compared to the ideal one-way communication entanglement-based satellite QKD protocol, which is effectively optimizing the HBEPP source brightness in accordance with system losses.</p>","PeriodicalId":72073,"journal":{"name":"Advanced quantum technologies","volume":"8 6","pages":""},"PeriodicalIF":4.4,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144273142","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}