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Dong Xie

Publications and source records attributed to Dong Xie.

At least 37 records · Page 2Linked to original sources
arXiv2025

Intelligent Soft Matter: Towards Embodied Intelligence

Intelligent soft matter stands at the intersection of materials science, physics, and cognitive science, promising to change how we design and interact with materials. This transformative field seeks to create materials that possess life-like capabilities, such as perception, learning, memory, and adaptive behavior. Unlike traditional materials, which typically perform static or predefined functions, intelligent soft matter dynamically interacts with its environment. It integrates multiple sensory inputs, retains experiences, and makes decisions to optimize its responses. Inspired by biological systems, these materials intend to leverage the inherent properties of soft matter: flexibility, self-evolving, and responsiveness to perform functions that mimic cognitive processes. By synthesizing current research trends and projecting their evolution, we present a forward-looking perspective on how intelligent soft matter could be constructed, with the aim of inspiring innovations in fields such as biomedical devices, adaptive robotics, and beyond. We highlight new pathways for integrating design of sensing, memory and action with internal low-power operations and discuss challenges for practical implementation of materials with "intelligent behavior". These approaches outline a path towards to more robust, versatile and scalable materials that can potentially act, compute, and "think" by their inherent intrinsic material behaviour beyond traditional smart technologies relying on external control.

cond-mat.soft↗
arXiv2025

Gravimetry enhanced by nonreciprocal optomechanical coupling

We explore how to measure the gravitational acceleration by using a dissipative optomechanical cavity. What is quite different from the conventional measurement methods is that we have constructed a nonreciprocal optomechanical coupling. We demonstrate that nonreciprocal coupling has a much greater advantage than reciprocal coupling. When the coherent optomechanical coupling is relatively weak and the driving intensity of single photon is strong, nonreciprocal coupling can improve the measurement precision by a factor of two. When the driving strength of single photon tends to infinity, reciprocal coupling fails to obtain any information about the gravitational acceleration, while nonreciprocal coupling still does. Using a two-photon driving, the measurement uncertainty of the gravitational acceleration will tend to zero as the intensity of two-photon driving approaches the critical point. The critical value of the two-photon driving intensity required for nonreciprocal coupling is finite, but the critical value of the two-photon driving intensity required for reciprocal coupling is infinite. The combination of the amplification of mechanical parameters and the extra force can not improve the measurement precision, but it can enhance the susceptibility. Furthermore, when the single-photon driving field is relatively weak, we analytically calculate the quantum Fisher information. The results show that, under most experimental parameters, nonreciprocal coupling still performs better than reciprocal coupling.

quant-ph↗
arXiv2025

Security Analysis of Thumbnail-Preserving Image Encryption and a New Framework

As a primary encryption primitive balancing the privacy and searchability of cloud storage images, thumbnail preserving encryption (TPE) enables users to quickly identify the privacy personal image on the cloud and request this image from the owner through a secure channel. In this paper, we have found that two different plaintext images may produce the same thumbnail. It results in the failure of search strategy because the collision of thumbnail occurs. To address this serious security issues, we conduct an in-depth analysis on the collision probabilities of thumbnails, and then propose a new TPE framework, called multi-factor thumbnail preserving encryption (MFTPE). It starts from the collision probability of two blocks, extend to the probabilities of two images and ultimately to N images. Then, we in detail describe three specific MFTPE constructions preserving different combinations of factors, i.e., the sum and the geometric mean, the sum and the range, and the sum and the weighted mean. The theoretical and experimental results demonstrate that the proposed MFTPE reduces the probability of thumbnails, exhibits strong robustness, and also effectively resists face detection and noise attacks.

cs.CR↗
arXiv2024

Dispersive Qubit Readout of Temperature

Squeezed light can exponentially increase the signal-to-noise ratio (SNR) of dispersive qubit readout, especially using a combination of injected external squeezing (IES) and intracavity squeezing (ICS). We further investigate whether IES and ICS can also exponentially improve the measurement precision of temperature. In the case of fully thermalized qubits isolated from thermal bath, the measurement precision of temperature can be improved exponentially when the temperature or measurement time or the input photon number approaches 0. In general, thermal fluctuations prevent the action of squeezed light. When multiple qubits maintain interacting with the thermal bath, the Heisenberg scaling can be achieved if the loss rate of the cavity is large and the coupling between the qubit and the optical cavity is weak enough. In the meantime, IES can also further promote the improvement of the measurement precision of the temperature exponentially.

quant-ph↗
arXiv2024

Nonreciprocal Quantum Sensing

Nonreciprocity can not only generate quantum resources, but also shield noise and reverse interference from driving signals. We investigate the advantages of nonreciprocal coupling in sensing a driving signal. In general, we find that the nonreciprocal coupling performs better than the corresponding reciprocal coupling. And we show that homodyne measurement is the optimal measurement. A single non-reciprocal coupling can increase measurement precision up to 2 times. Using $N$ non-reciprocal couplings in parallel, the measurement precision can be improved by $N^2$ times compared with the corresponding reciprocal coupling. In a non-zero temperature dissipative environment, we demonstrate that the nonreciprocal quantum sensing has better robustness to thermal noise than the reciprocal quantum sensing.

quant-ph↗
arXiv2024

On the minimal number of closed geodesics on positively curved Finsler spheres

In this paper, we proved that for every Finsler metric on $S^n$ $(n\ge 4)$ with reversibility $λ$ and flag curvature $K$ satisfying $(\frac{2n-3}{n-1})^2 (\fracλ{λ+1})^2<K\le 1$ and $ λ<\frac{n-1}{n-2} $, there exist at least $n$ prime closed geodesics on $(S^n,F)$, which solved a conjecture of Katok and Anosov for such positivley curved spheres when $n$ is even. Furthermore, if the number of closed geodesics on such positively curved Finsler $S^n$ is finite, then there exist at least $2\left[\frac{n}{2}\right]-1$ non-hyperbolic closed geodesics.

math.DG↗
arXiv2024

Quantum metrology in a driven-dissipation down-conversion system beyond the parametric approximation

We investigate quantum metrology in a degenerate down-conversion system composed of a pump mode and two degenerate signal modes. In the conventional parametric approximation, the pump mode is assumed to be constant, not a quantum operator. We obtain the measurement precision of the coupling strength between the pump mode and two degenerate signal modes beyond the parametric approximation. Without a dissipation, the super-Heisenberg limit can be obtained when the initial state is the direct product of classical state and quantum state. This does not require the use of entanglement resources which are not easy to prepare. When the pump mode suffers from a single-photon dissipation, the measurement uncertainty of the coupling strength is close to 0 as the coupling strength approaches 0 with a coherent driving. The direct photon detection is proved to be the optimal measurement. This result has not been changed when the signal modes suffer from the two-photon dissipation. When the signal modes also suffer from the single-mode dissipation, the information of the coupling strength can still be obtained in the steady state. In addition, the measurement uncertainty of the coupling strength can also be close to 0 and become independent of noise temperature as the critical point between the normal and superradiance phase approaches. Finally, we show that a driven-dissipation down-conversion system can be used as a precise quantum sensor to measure the driving strength.

quant-ph↗
arXiv2023

Thermometry with a Dissipative Heavy Impurity

Improving the measurement precision of low temperature is significant in fundamental science and advanced quantum technology application. However, the measurement precision of temperature $T$ usually diverges as $T$ tends to 0. Here, by utilizing a heavy impurity to measure the temperature of a Bose gas, we obtain the Landau bound to precision $δ^2 T\propto T^2$ to avoid the divergence. Moreover, when the initial momentum of the heavy impurity is fixed and non-zero, the measurement precision can be $δ^2 T\propto T^3$ to break the Landau bound. We derive the momentum distribution of the heavy impurity at any moment and obtain the optimal measurement precision of the temperature by calculating the Fisher information. As a result, we find that enhancing the expectation value of the initial momentum can help to improve the measurement precision. In addition, the momentum measurement is the optimal measurement of the temperature in the case of that the initial momentum is fixed and not equal to 0. The kinetic energy measurement is the optimal measurement in the case of that the expectation value of the initial momentum is 0. Finally, we obtain that the temperatures of two Bose gases can be measured simultaneously. The simultaneous measurement precision is proportional to $T^2$ when two temperatures are close to $T$.

quant-ph↗
arXiv2023

An Effective Two-stage Training Paradigm Detector for Small Dataset

Learning from the limited amount of labeled data to the pre-train model has always been viewed as a challenging task. In this report, an effective and robust solution, the two-stage training paradigm YOLOv8 detector (TP-YOLOv8), is designed for the object detection track in VIPriors Challenge 2023. First, the backbone of YOLOv8 is pre-trained as the encoder using the masked image modeling technique. Then the detector is fine-tuned with elaborate augmentations. During the test stage, test-time augmentation (TTA) is used to enhance each model, and weighted box fusion (WBF) is implemented to further boost the performance. With the well-designed structure, our approach has achieved 30.4% average precision from 0.50 to 0.95 on the DelftBikes test set, ranking 4th on the leaderboard.

cs.CV↗
arXiv2023

The Effect of Ionic Spin on Multiferroic of Orthorhombic Perovskite

To investigate the influence of ion spin on the coupling between ferromagnetism and ferroelectricity in type II multiferroic perovskite, we prepared the multiferroic perovskite Er0.9La0.1Cr0.8Fe0.2O3 (ELCFO) using the sol-gel method, and explored the macroscopic magnetic properties of ELCFO through Mössbauer spectrum and magnetic testing. The thermal magnetic curve was analyzed to examine the state and change of each ionic spin in the ELCFO system at different temperature ranges, and the role of ionic spin in the coupling between ferromagnetism and ferroelectricity was investigated. This study provides a theoretical basis for further research on multiferroic perovskites and has practical implications.

cond-mat.mtrl-sci↗
arXiv2023

Quantum estimation of tripartite coupling in Spin-Magnon-Mechanical Hybrid Systems

Tripartite interactions play a fundamental role in the quantum information processing and quantum technology. However, it is generally difficult to realize strong tripartite coupling. We investigate the estimation of a tripartite coupling strength in a hybrid setup composed of a single nitrogen-vacancy (NV) center and a micromagnet. A time-independent parametric drive can be utilized to increase the estimation precision of the tripartite coupling strength. By calculating the quantum Fisher information (QFI), we can obtain the optimal estimation precision by measuring the eigenstate of the tripartite system. At the critical position, the QFI is divergent due to that the preparation time of the eigenstate is divergent. When the system is subjected to a dissipation, the QFI near the critical point of the driven-dissipation phase transition is analytically obtained. The direct intensity measurement is the optimal measurement near the dissipation phase transition point. In addition, we quantify the robustness of an imperfect measurement operator by the measurement noise susceptibility based on the error propagation formula. We find that the direct intensity measurement is enough robust against small measurement disturbance from a coherent drive. But it can be disturbed by the nonlinear anti-harmonic measurement noise, especially near the critical point.

quant-ph↗
arXiv2023

Exceptional point in self-consistent Markovian master equations

Exceptional point (EP) denotes the non-Hermitian degeneracy, in which both eigenvalues and eigenstates become identical. By the conventional local Markovian master equation, EP can be constructed by parity-time (PT) or anti-PT symmetry in a system composed of coupled subsystems. However, the coupling between two systems makes the conventional local Markovian master equation become inconsistent. By using the self-consistent Markovian master equation, we show that there is no EP in the system composed of two bosonic subsystems. We further prove that the conventional local master equation can be valid only when the coupling strength is much smaller than the difference in resonance frequency between the two subsystems, rather than the resonance frequencies. In a system composed of three bosonic subsystems, EP can be obtained by adiabatically eliminating one of the three subsystems.

quant-ph↗
arXiv2023

Multiplicity of closed geodesics on bumpy Finsler manifolds with elliptic closed geodesics

Let $M$ be a compact simply connected manifold satisfying $H^*(M;\mathbf{Q})\cong T_{d,n+1}(x)$ for integers $d\ge 2$ and $n\ge 1$. If all prime closed geodesics on $(M,F)$ with an irreversible bumpy Finsler metric $F$ are elliptic, either there exist exactly $\frac{dn(n+1)}{2}$ (when $d\ge 2$ is even) or $(d+1)$ (when $d\ge 3$ is odd) distinct closed geodesics, or there exist infinitely many distinct closed geodesics.

math.SG↗
arXiv2022

Zeroth-Order Stochastic Coordinate Methods for Decentralized Non-convex Optimization

In this letter, we first propose a \underline{Z}eroth-\underline{O}rder c\underline{O}ordinate \underline{M}ethod~(ZOOM) to solve the stochastic optimization problem over a decentralized network with only zeroth-order~(ZO) oracle feedback available. Moreover, we equip a simple mechanism "powerball" to ZOOM and propose ZOOM-PB to accelerate the convergence of ZOOM. Compared with the existing methods, we verify the proposed algorithms through two benchmark examples in the literature, namely the black-box binary classification and the generating adversarial examples from black-box DNNs in order to compare with the existing state-of-the-art centralized and distributed ZO algorithms. The numerical results demonstrate a faster convergence rate of the proposed algorithms.

math.OC↗
arXiv2022

Multiplicity and stability of closed geodesics on positively curved Finsler $4$-spheres

In this paper, we prove that for every Finsler $4$-dimensional sphere $(S^4,F)$ with reversibility $λ$ and flag curvature $K$ satisfying $\frac{25}{9}\left(\fracλ{1+λ}\right)^2<K\le 1$ with $λ<\frac{3}{2}$, either there exist at least four prime closed geodesics, or there exist exactly three prime non-hyperbolic closed geodesics and at least two of them are irrationally elliptic.

math.DG↗
arXiv2022

Quantum metrology with quantum Wheatstone bridge composed of Bose systems

The quantum version of a special classical Wheatstone bridge built with a boundary-driven spin system has recently been proposed. We propose a quantum Wheatstone bridge consisting of Bose systems, which can simulate the general classical Wheatstone bridge. Unknown coupling can be obtained when the quantum Wheatstone bridge is balanced, which can be determined simply by the homodyne detection. When the expectation value of the homodyne detection is 0, the quantum Wheatstone bridge is unbalanced. Regulate a known coupling strength to make the expectation value of the homodyne detection be proportional to the square root of the initial number of bosons, which means that the quantum Wheatstone bridge is balanced. By calculating the quantum Fisher information, we show that the measurement precision is optimal when the quantum Wheatstone bridge is balanced. And the homodyne detection is close to the optimal measurement in the case of low-temperature baths.

quant-ph↗
arXiv2022

Optimal temperature estimation in polariton Bose-Einstein Condensate

Improving the measurement precision of temperature is very important and challenging, especially in the low temperature range. Based on the existence of invariant subspaces during the polariton thermalization, we propose a new way to enhance the measurement precision of the low temperature and obtain Landau bound to avoid that the measurement uncertainty of the temperature diverges as the temperature approaches zero. The measurement precision of the low temperature increases significantly with the number of polariton states. In order to resist the dissipation, the incoherent pumping is necessary for obtaining the information of the temperature encoded in the steady state. It should be noted that too strong incoherent pumping is wasteful due to that the quantum Fisher information of the temperature becomes less and less dependent on the total number of the polaritons.

cond-mat.quant-gas↗