{"title":"QSSS-LTE: quantum secret sharing scheme over lattice-based threshold encryption","authors":"Xiuli Song, Tianai Xu, Yousheng Zhou and Tao Wu","doi":"10.1088/2058-9565/adff2f","DOIUrl":"https://doi.org/10.1088/2058-9565/adff2f","url":null,"abstract":"This paper proposed a quantum secret sharing scheme over lattice-based threshold encryption: it integrates resplittable threshold public key encryption (RTPKE) and utilizes a lattice-based private key share transmission mechanism to enhance the security of the share distribution process. By leveraging the dynamic key management features of RTPKE, the scheme can flexibly adjust key distribution as required when participants change. During the quantum secret reconstruction process, the decoy particles do not need to be detected by eavesdroppers when transmitted between participants. Instead, this task is performed by a semi-trusted third party (TP), reducing resource consumption and communication overhead. The decoy particles are not chosen from a fixed quantum bases but are instead in completely random quantum bases, making it impossible for an eavesdropper to obtain the correct result through conventional measurements. The probability of the eavesdropper escaping detection after measuring any decoy particle is nearly zero. After each participant performs a unitary operation, they randomly shuffle the sequence of decoy and information particles. When the particles are transmitted back to the TP, the TP uses the sequence information recorded by the participants to restore the original order and extract the information particles, effectively defending against forgery-replay attacks and potential threats from dishonest participants.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"31 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145008960","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}
Isabell Jauch, Artur Skljarow, Thomas Strohm, Florian Dolde, Tino Fuchs and Fedor Jelezko
{"title":"Enhancing the Ramsey contrast of an NV-ensemble in diamond using quantum optimal control","authors":"Isabell Jauch, Artur Skljarow, Thomas Strohm, Florian Dolde, Tino Fuchs and Fedor Jelezko","doi":"10.1088/2058-9565/adffb2","DOIUrl":"https://doi.org/10.1088/2058-9565/adffb2","url":null,"abstract":"Negatively charged nitrogen-vacancy (NV) centers in diamonds are commonly used in quantum magnetometry. However, the potential of this approach is often limited by the inhomogeneity of the driving field. In this study, we explore the potential of closed-loop quantum optimal control to improve DC Ramsey magnetometry with NV-ensembles suffering from inhomogeneous microwave (MW) fields and MW power limitations. We demonstrate an improvement of the optically detected Ramsey contrast up to a factor of 3.13. This enables noticeable power savings for miniaturized devices without loss in magnetometry performance. Additionally, we show a recovery of 86.3% of the Ramsey contrast in presence of a five times less homogeneous MW field compared to the homogeneous field of a MW Helmholtz coil pair.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"28 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144995556","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}
Poetri Sonya Tarabunga, Martina Frau, Tobias Haug, Emanuele Tirrito and Lorenzo Piroli
{"title":"A nonstabilizerness monotone from stabilizerness asymmetry","authors":"Poetri Sonya Tarabunga, Martina Frau, Tobias Haug, Emanuele Tirrito and Lorenzo Piroli","doi":"10.1088/2058-9565/adfd0d","DOIUrl":"https://doi.org/10.1088/2058-9565/adfd0d","url":null,"abstract":"We introduce a nonstabilizerness monotone which we name basis-minimized stabilizerness asymmetry (BMSA). It is based on the notion of G-asymmetry, a measure of how much a certain state deviates from being symmetric with respect to a symmetry group G. For pure states, we show that the BMSA is a strong monotone for magic-state resource theory, while it can be extended to mixed states via the convex roof construction. We discuss its relation with other magic monotones, first showing that the BMSA coincides with the recently introduced basis-minimized measurement entropy, thereby establishing the strong monotonicity of the latter. Next, we provide inequalities between the BMSA and other nonstabilizerness measures such as the robustness of magic, stabilizer extent, stabilizer rank, stabilizer fidelity and stabilizer Rényi entropy. We also prove that the stabilizer fidelity, stabilizer Rényi entropy and BMSA with index have the same asymptotic scaling with qubit number. Finally, we present numerical methods to compute the BMSA, highlighting its advantages and drawbacks compared to other nonstabilizerness measures in the context of pure many-body quantum states. We also discuss the importance of additivity and strong monotonicity for measures of nonstabilizerness in many-body physics, motivating the search for additional computable nonstabilizerness monotones.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"35 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144924090","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":"Quantum ergodicity and scrambling in quantum annealers","authors":"Manuel H Muñoz-Arias and Pablo M Poggi","doi":"10.1088/2058-9565/adfc08","DOIUrl":"https://doi.org/10.1088/2058-9565/adfc08","url":null,"abstract":"Quantum annealers play a major role in the ongoing development of quantum information processing and in the advent of quantum technologies. Their functioning is underpinned by the many-body adiabatic evolution connecting the ground state of a simple system to that of an interacting classical Hamiltonian which encodes the solution to an optimization problem. Here we explore more general properties of the dynamics of quantum annealers, going beyond the low-energy regime. We show that the unitary evolution operator describing the complete dynamics is typically highly quantum chaotic. As a result, the annealing dynamics naturally leads to volume-law entangled random-like states when the initial configuration is rotated away from the low-energy subspace. Furthermore, we observe that the Heisenberg dynamics of a quantum annealer leads to extensive operator spreading, a hallmark of quantum information scrambling. In contrast, we find that when the annealing schedule is returned to the initial configuration (i.e. via a cyclic ramp), a subtle interplay between chaos and adiabaticity emerges, and the dynamics shows strong deviations from full ergodicity.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"8 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144924089","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":"Variational quantum algorithm for constrained topology optimization","authors":"Jungin E Kim and Yan Wang","doi":"10.1088/2058-9565/adfc92","DOIUrl":"https://doi.org/10.1088/2058-9565/adfc92","url":null,"abstract":"One of the challenging scientific computing problems is topology optimization (TO), where the two tasks of searching through the combinatorially complex configurations and solving the constraints of partial differential equations need to be done simultaneously. In this paper, a novel variational quantum algorithm for constrained TO is proposed, which allows for the single-loop parallel search for the optimal configuration that also satisfies the physical constraints. The optimal configurations and the solutions to physical constraints are encoded with two separate quantum registers. A constraint encoding scheme is also proposed to incorporate volume and connectivity constraints in optimization. The gate complexity of the proposed quantum algorithm is analyzed. The algorithm is demonstrated with compliance minimization problems including truss structures and Messerschmitt–Bölkow–Blohm beams.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"29 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144915809","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}
Adithya Sireesh, Abdulla Alhajri, M S Kim and Tobias Haug
{"title":"Disentangling quantum autoencoder","authors":"Adithya Sireesh, Abdulla Alhajri, M S Kim and Tobias Haug","doi":"10.1088/2058-9565/adfc07","DOIUrl":"https://doi.org/10.1088/2058-9565/adfc07","url":null,"abstract":"Entangled quantum states are highly sensitive to noise, which makes it difficult to transfer them over noisy quantum channels or to store them in quantum memory. Here, we propose the disentangling quantum autoencoder (DQAE) to encode entangled states into single-qubit product states. The DQAE provides an exponential improvement in the number of copies needed to transport entangled states across qubit-loss or leakage channels compared to unencoded states. The DQAE can be trained in an unsupervised manner from entangled quantum data. For general states, we train via variational quantum algorithms based on gradient descent with purity-based cost functions, while stabilizer states can be trained via a Metropolis algorithm. For particular classes of states, the number of training data needed to generalize is surprisingly low: for stabilizer states, DQAE generalizes by learning from a number of training data that scales linearly with the number of qubits, while only 1 training sample is sufficient for states evolved with the transverse-field Ising Hamiltonian. Our work provides practical applications for enhancing near-term quantum computers.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"32 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144905993","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}
Diego H Useche, Sergio Quiroga-Sandoval, Sebastian L Molina, Vladimir Vargas-Calderón, Juan E Ardila-García and Fabio A González
{"title":"Quantum generative classification with mixed states","authors":"Diego H Useche, Sergio Quiroga-Sandoval, Sebastian L Molina, Vladimir Vargas-Calderón, Juan E Ardila-García and Fabio A González","doi":"10.1088/2058-9565/adf350","DOIUrl":"https://doi.org/10.1088/2058-9565/adf350","url":null,"abstract":"Classification can be performed using either a discriminative or a generative learning approach. Discriminative learning consists of constructing the conditional probability of the outputs given the inputs, while generative learning consists of constructing the joint probability density of the inputs and outputs. Although most classical and quantum methods are discriminative, there are some advantages of the generative learning approach. For instance, it can be applied to unsupervised learning, statistical inference, uncertainty estimation, and synthetic data generation. In this article, we present a quantum generative multiclass classification strategy, called quantum generative classification (QGC). This model uses a variational quantum algorithm to estimate the joint probability density function of features and labels of a data set by means of a mixed quantum state. We also introduce a quantum map called quantum-enhanced Fourier features, which leverages quantum superposition to prepare high-dimensional data samples in quantum hardware using a small number of qubits. We show that the QGC algorithm can be viewed as a Gaussian mixture that reproduces a kernel Hilbert space of the training data. In addition, we developed a hybrid quantum–classical neural network that shows that it is possible to perform generative classification on high-dimensional data sets. The method was tested on various low- and high-dimensional data sets including the 10-class MNIST and Fashion-MNIST data sets, illustrating that the generative classification strategy is competitive against other previous quantum models.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"56 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144905992","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}
Linda Sansoni, Eleonora Stefanutti and Andrea Chiuri
{"title":"An experimental investigation of quantum frequency correlations resilience against white and colored noise","authors":"Linda Sansoni, Eleonora Stefanutti and Andrea Chiuri","doi":"10.1088/2058-9565/adf7d0","DOIUrl":"https://doi.org/10.1088/2058-9565/adf7d0","url":null,"abstract":"Quantum technologies based on photons rely on correlated pairs generated through nonlinear optics. Hence, understanding the impact of disturbances is of paramount importance for the development of this innovative field. Here we focus on the quantum spectroscopy as one of the most promising quantum technique showing a realistic perspective for a future employment. In this field, the most interesting disturbance is represented by the frequency noise. We present an experiment aimed at testing and characterizing the resilience against different levels of white and colored noise and we include simulations to generalize our findings. With this work we demonstrate that the spectroscopical properties of both the target and the noise, as well as the strength of the quantum correlations, play a crucial role and could have e huge impact on the performances, especially in terms of achievable spectral resolution. Remarkably, the presence of a specific region where the technology is always robust against any kind of noise represents an advantage allowing to deal with optimal measurements and fully exploit the capabilities of this technology.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"14 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144898143","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":"Complexity of Gaussian quantum optics with a limited number of non-linearities","authors":"Michael G Jabbour and Leonardo Novo","doi":"10.1088/2058-9565/adf6d4","DOIUrl":"https://doi.org/10.1088/2058-9565/adf6d4","url":null,"abstract":"It is well known in quantum optics that any process involving the preparation of a multimode Gaussian state, followed by a Gaussian operation and Gaussian measurements, can be efficiently simulated by classical computers. Here, we provide evidence that computing transition amplitudes of Gaussian processes with a single-layer of non-linearities is hard for classical computers. To this end, we show how an efficient algorithm to solve this problem could be used to efficiently approximate outcome probabilities of a Gaussian boson sampling experiment. We also extend this complexity result to the problem of computing transition probabilities of Gaussian processes with two layers of non-linearities, by developing a Hadamard test for continuous-variable systems that may be of independent interest. Given recent experimental developments in the implementation of photon-photon interactions, our results may inspire new schemes showing quantum computational advantage or algorithmic applications of non-linear quantum optical systems realizable in the near-term.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"10 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144898142","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}
Jingyan Feng, Mohan Zhang, Matteo Fadel and Tim Byrnes
{"title":"Quantum teleportation of cat states with binary-outcome measurements","authors":"Jingyan Feng, Mohan Zhang, Matteo Fadel and Tim Byrnes","doi":"10.1088/2058-9565/adf572","DOIUrl":"https://doi.org/10.1088/2058-9565/adf572","url":null,"abstract":"We propose a teleportation protocol involving beam splitting operations and binary-outcome measurements, such as parity measurements. These operations have a straightforward implementation using the dispersive regime of the Jaynes–Cummings Hamiltonian, making our protocol suitable for a broad class of platforms, including trapped ions, circuit quantum electrodynamics and acoustodynamics systems. In these platforms homodyne measurements of the bosonic modes are less natural than dispersive measurements, making standard continuous variable teleportation unsuitable. In our protocol, Alice is in possession of two bosonic modes and Bob a single mode. An entangled mode pair between Alice and Bob is created by performing a beam splitter operation on a cat state. An unknown qubit state encoded by cat states is then teleported from Alice to Bob after a beamsplitting operation, measurement sequence, and a conditional correction. In the case of multiple measurements, near-perfect fidelity can be obtained. We discuss the optimal parameters in order to maximize the fidelity under a variety of scenarios.","PeriodicalId":20821,"journal":{"name":"Quantum Science and Technology","volume":"190 1","pages":""},"PeriodicalIF":6.7,"publicationDate":"2025-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144898141","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}