arXiv subjects

Tingyu Zhang

Publications and source records attributed to Tingyu Zhang.

17 recordsLinked to original sources

arXiv2026

Nonequilibrium Andreev transport at the QGP-2SC interface

We discuss a nonequilibrium Andreev reflection at an interface between quark-gluon plasma (QGP) and two-flavor color superconducting (2SC) quark matter. Based on the Schwinger-Keldysh framework and a relativistic tunneling model, we evaluate the momentum-resolved tunneling current generated by a chemical-potential bias between the QGP and 2SC phases. We find that the Andreev reflection appears as at the fourth order of the tunneling strength, in which an incident quark in QGP is converted into a reflected hole, while a Cooper pair is injected into the 2SC condensate. We show that the Andreev reflection is enhanced when the bias becomes comparable to the gap and is suppressed in the supergap region, which is similar to that in superconducting materials. The present formulation provides a field-theoretical pathway to strongly-correlated transport across dense-matter interfaces relevant to nonequilibrium dynamics in compact stars.

nucl-th↗

arXiv2026

Noise spectroscopy of two-body loss as a probe of dynamical bulk viscosity in ultracold atomic gases

We show that the correlated noise of the two-body loss current provides access to the dynamical bulk viscosity in weakly dissipative quantum gases. Starting from the Lindblad equation for weak inelastic losses, we derive the loss-current operator. After subtracting the leading Poissonian shot-noise background, the remaining noise power spectrum of two-body loss current is found proportional to the equilibrium correlation function of the contact operator. Combining this result with the exact relation between contact correlations and bulk viscosity, we demonstrate the correspondence between the measurable loss-current noise and the bulk-viscosity. Our result identifies the higher-order fluctuation of two-body loss as a probe of dynamical bulk viscosity, whose measurement has remained elusive in experiments.

cond-mat.quant-gas↗

arXiv2026

Josephson effects in an interaction-asymmetric junction across the BCS-BEC crossover

We theoretically study the Josephson effect in ultracold Fermi gases, where the two sides of the Josephson junction are independently tuned to different regions of the Bardeen-Cooper-Schrieffer (BCS)-Bose-Einstein condensation (BEC) crossover. Using the nonequilibrium Green's function approach combined with the tunnel Hamiltonian formalism and a mean-field approach, we evaluate the DC and AC Josephson currents throughout the entire crossover region. We calculate the DC Josephson current as a function of interaction strength by tuning both sides of the junction synchronously from the BCS to the BEC regimes, and give the asymptotic expression of the current in the deep BCS and BEC limits. We also study the AC Josephson junction through the interaction-asymmetric junction by fixing the interaction in one reservoir and tuning that of the other one. A peak of the tunneling current is found when one side is fixed in the BCS limit and the other side is tuned into the BEC regime, which corresponds to the interaction-biased Riedel peak. Our results indicate the competition between contributions of increasing pair spectral weight and decreasing chemical potential to Josephson tunneling throughout the BCS-BEC crossover, and demonstrate the realization of the Riedel peak in strong-coupling quantum gases.

cond-mat.quant-gas↗

arXiv2026

Understanding User Requirements for Creating Sensor-Powered Smart Car Cabins Through Retrofitting

In this paper, we explore a novel approach that leverages retrofitting to create sensor-powered smart car cabins. We propose that retrofitting offers a promising way to complement and extend the capabilities of built-in smart cabin sensors provided by car manufacturers. To understand how retrofitting solutions should be designed, we conducted a two-phase study. First, through semi-structured interviews with 18 participants, we examined challenges with built-in smart cabin sensors and identified opportunities where retrofitting could address these limitations. Second, through probe-based participatory design sessions with 15 participants, we identified user requirements and expectations for effective retrofit solutions. Based on our findings, we present a set of design recommendations to guide the future development of retrofit methods for smart car cabins.

cs.HC↗

arXiv2025

Hybrid Combinatorial Multi-armed Bandits with Probabilistically Triggered Arms

The problem of combinatorial multi-armed bandits with probabilistically triggered arms (CMAB-T) has been extensively studied. Prior work primarily focuses on either the online setting where an agent learns about the unknown environment through iterative interactions, or the offline setting where a policy is learned solely from logged data. However, each of these paradigms has inherent limitations: online algorithms suffer from high interaction costs and slow adaptation, while offline methods are constrained by dataset quality and lack of exploration capabilities. To address these complementary weaknesses, we propose hybrid CMAB-T, a new framework that integrates offline data with online interaction in a principled manner. Our proposed hybrid CUCB algorithm leverages offline data to guide exploration and accelerate convergence, while strategically incorporating online interactions to mitigate the insufficient coverage or distributional bias of the offline dataset. We provide theoretical guarantees on the algorithm's regret, demonstrating that hybrid CUCB significantly outperforms purely online approaches when high-quality offline data is available, and effectively corrects the bias inherent in offline-only methods when the data is limited or misaligned. Empirical results further demonstrate the consistent advantage of our algorithm.

cs.LG↗

arXiv2025

Schwinger-Keldysh approach to tunneling transport at a hadron-quark interface

We theoretically discuss quantum tunneling transport and frictions at a hadron-quark matter interface based on the Schwinger-Keldysh approach combined with the tunneling Hamiltonian, which has been developed in the context of condensed matter physics. In the inner core of massive neutron stars, it is expected that cold quark matter appears at sufficiently high densities and hence exhibits color superconductivity, surrounded by nucleon superfluids at lower densities. The perturbative expressions of the tunneling current and the friction at the interface are obtained in terms of the non-equilibrium Green's functions. We demonstrate the DC Josephson current that occurs at the hadron-quark superfluid interface in the present scheme. Our framework can be applied to various conflagrations involving the interfaces relevant to astrophysical phenomena.

nucl-th↗

arXiv2025

Pharmacokinetic characteristics of Jinhong tablets in normal, chronic superficial gastritis and intestinal microbial disorder rats

Jinhong tablet (JHT), a traditional Chinese medicine made from four herbs, effectively treats chronic superficial gastritis (CSG) by soothing the liver, relieving depression, regulating qi, and promoting blood circulation. However, its pharmacokinetics are underexplored. This study investigates JHT's pharmacokinetics in normal rats and its differences in normal, CSG, and intestinal microbial disorder rats. A quantitative method for seven active ingredients in rat plasma was established using UPLC-TQ-MS/MS. After administering various JHT doses, plasma concentrations were measured to assess pharmacokinetics in normal rats. The pharmacokinetics of four main ingredients were compared in normal, CSG, and fecal microbiota transplantation (FMT) rats. Intestinal microbial changes were evaluated by high-throughput sequencing. Spearman correlation analysis linked ingredient exposure to gut microbiota disturbances. The method showed good linearity, precision, accuracy, extraction recovery, and stability. In normal rats, all seven ingredients were rapidly absorbed. Tetrahydropalmatine, corydaline, costunolide, and rhamnosylvitexin had good exposure, while dehydrocorydaline, allocryptopine, and palmatine hydrochloride had low exposure. Tetrahydropalmatine, corydaline, and costunolide followed linear pharmacokinetics (AUC0-t, Cmax) at doses of 0.7-5.6 g/kg, while rhamnosylvitexin and dehydrocorydaline showed linearity at 0.7-2.8 g/kg. In CSG and FMT rats, pharmacokinetic differences were observed. CSG enhanced costunolide exposure and Cmax, and increased rhamnosylvitexin exposure. FMT raised corydaline exposure and rhamnosylvitexin Cmax, linked to 20 bacterial genera.

q-bio.QM↗

arXiv2025

Integrating network pharmacology, metabolomics, and gut microbiota analysis to explore the effects of Jinhong tablets on chronic superficial gastritis

Chronic superficial gastritis (CSG) severely affects quality of life and can progress to worse gastric pathologies. Traditional Chinese Medicine (TCM) effectively treats CSG, as exemplified by Jinhong Tablets (JHT) with known anti-inflammatory properties, though their mechanism remains unclear. This study integrated network pharmacology, untargeted metabolomics, and gut microbiota analyses to investigate how JHT alleviates CSG. A rat CSG model was established and evaluated via H&E staining. We identified JHT's target profiles and constructed a multi-layer biomolecular network. Differential metabolites in plasma were determined by untargeted metabolomics, and gut microbiota diversity/composition in fecal and cecal samples was assessed via 16S rRNA sequencing. JHT markedly reduced gastric inflammation. Network pharmacology highlighted metabolic pathways, particularly lipid and nitric oxide metabolism, as essential to JHT's therapeutic effect. Metabolomics identified key differential metabolites including betaine (enhancing gut microbiota), phospholipids, and citrulline (indicating severity of CSG). Pathway enrichment supported the gut microbiota's involvement. Further microbiota analysis showed that JHT increased betaine abundance, improved short-chain fatty acid production, and elevated Faecalibaculum and Bifidobacterium, thereby alleviating gastric inflammation. In conclusion, JHT alleviates CSG via diverse metabolic processes, especially lipid and energy metabolism, and influences metabolites like betaine alongside gut microbes such as Faecalibaculum and Bifidobacterium. These findings underscore JHT's therapeutic potential and deepen our understanding of TCM's role in CSG management.

q-bio.MN↗

arXiv2024

Supersymmetry-like tunneling current noise as a probe of Goldstino excitation in a Bose-Fermi mixture

The Goldstino, which is a fermionic Nambu-Goldstone mode, has been predicted in a Bose-Fermi mixture when the supersymmetry is broken. To detect this excitation mode, we theoretically investigate the shot noise of the supersymmetry-like tunneling current in a weakly interacting ultracold Bose-Fermi mixture. The Fano factor, which is defined by the noise-to-current ratio, reflect the elementary carriers of the tunneling process. The change of the Fano factor microscopically as the density changes evinces a crossover from the quasiparticle transport to multiparticle (Goldstino) transport. The tunneling channel can also be changed by tuning the potential barrier.

cond-mat.quant-gas↗

arXiv2024

Probing Goldstino excitation through the tunneling transport in a Bose-Fermi mixture with explicitly broken supersymmetry

We theoretically investigate the tunneling transport in a repulsively interacting ultracold Bose-Fermi mixture. A two-terminal model is applied to such a mixture and the supersymmetric-like tunneling current through the junction can be induced by the bias of fermion chemical potential between two reservoirs. The Goldstino, which is the Nambu-Goldstone fermionic mode associated with the spontaneous sypersymmetry breaking and appears as a gapped mode in the presence of the explicit supersymmetry breaking in existing Bose-Fermi mixtures, is found to contribute to the tunneling transport as a supercharge exchanging process. Our study provides a potential way to detect the Goldstino transport in cold atom experiments.

cond-mat.quant-gas↗

arXiv2024

Magnonic spin current shot noise in an itinerant Fermi gas

Spin transport phenomena at strongly-correlated interfaces play central roles in fundamental physics as well as spintronic applications. To anatomize spin-transport carriers, we propose the detection of the spin current noise in interacting itinerant fermions. The Fano factor given by the ratio between the spin current and its noise reflects elementary carriers of spin transport at the interface of spin-polarized Fermi gases realized in ultracold atoms. The change of the Fano factor microscopically evinces a crossover from the quasiparticle transport to magnon transport in itinerant fermionic systems.

cond-mat.quant-gas↗

arXiv2023

MToP: A MATLAB Benchmarking Platform for Evolutionary Multitasking

Evolutionary multitasking (EMT) has emerged as a popular topic of evolutionary computation over the past decade. It aims to concurrently address multiple optimization tasks within limited computing resources, leveraging inter-task knowledge transfer techniques. Despite the abundance of multitask evolutionary algorithms (MTEAs) proposed for multitask optimization (MTO), there remains a need for a comprehensive software platform to help researchers evaluate MTEA performance on benchmark MTO problems as well as explore real-world applications. To bridge this gap, we introduce the first open-source benchmarking platform, named MToP, for EMT. MToP incorporates over 50 MTEAs, more than 200 MTO problem cases with real-world applications, and over 20 performance metrics. Based on these, we provide benchmarking recommendations tailored for different MTO scenarios. Moreover, to facilitate comparative analyses between MTEAs and traditional evolutionary algorithms, we adapted over 50 popular single-task evolutionary algorithms to address MTO problems. Notably, we release extensive pre-run experimental data on benchmark suites to enhance reproducibility and reduce computational overhead for researchers. MToP features a user-friendly graphical interface, facilitating results analysis, data export, and schematic visualization. More importantly, MToP is designed with extensibility in mind, allowing users to develop new algorithms and tackle emerging problem domains. The source code of MToP is available at: https://github.com/intLyc/MTO-Platform

cs.NE↗

arXiv2023

Spin transport between polarized Fermi gases near the ferromagnetic phase transition

We theoretically study the spin current between two polarized Fermi gases with repulsive interactions near the itinerant ferromagnetic phase transition. We consider a two-terminal model where the left reservoir is fixed to be fully polarized while the polarization of the right reservoir is tuned through a fictitious magnetic field defined by the chemical-potential difference between different atomic hyperfine states. We calculate the spectra of the spin-flip susceptibility function, which displays a magnon dispersion emerging from the Stoner continuum at low momentum in the ferromagnetic phase. Based on the spin-flip susceptibility and using Keldysh Green's function formalism, we investigate the spin current induced by quasiparticle and spin-flip tunneling processes, respectively, and show their dependence on the polarization bias between two reservoirs. The one-body (quasiparticle) tunneling demonstrates a linear dependence with respect to the polarization bias. In contrast, the spin-flip process manifests a predominantly cubic dependence on the bias. While indicating an enhanced magnon tunneling in the strong-coupling regime, our results also demonstrate a characteristic behavior around the critical repulsive strength for ferromagnetic phase transition at low temperatures.

cond-mat.quant-gas↗

arXiv2023

Network pharmacology on the mechanism of Yi Qi Tong Qiao Pill inhibiting allergic rhinitis

Objective: The purpose of this study is to reveal the mechanism of action of Yi Qi Tong Qiao Pill (YQTQP) in the treatment of allergic rhinitis (AR), as well as establish a paradigm for the researches on traditional Chinese medicine (TCM) from systematic perspective. Methods: Based on the data collected from TCM-related and disease-related databases, target profiles of compounds in YQTQP were calculated through network-based algorithms and holistic targets of TQTQP was constructed. Network target analysis was performed to explore the potential mechanisms of YQTQP in the treatment of AR and the mechanisms were classified into different modules according to their biological functions. Besides, animal and clinical experiments were conducted to validate our findings inferred from Network target analysis. Results: Network target analysis showed that YQTQP targeted 12 main pathways or biological processes related to AR, represented by those related to IL-4, IFN-γ, TNF-α and IL-13. These results could be classified into 3 biological modules, including regulation of immune and inflammation, epithelial barrier disorder and cell adhesion. Finally, a series of experiments composed of animal and clinical experiments, proved our findings and confirmed that YQTQP could improve related symptoms of AR, like permeability of nasal mucosa epithelium. Conclusion: A combination of Network target analysis and the experimental validation indicated that YQTQP was effective in the treatment of AR and might provide a new insight on revealing the mechanism of TCM against diseases.

q-bio.QM↗

arXiv2023

Dominant Andreev Reflection through Nonlinear Radio-Frequency Transport

We theoretically propose the laser-induced Andreev reflection between two-component Fermi superfluid and normal states via spatially-uniform Rabi couplings. By analyzing the tunneling current between the superfluid and normal states up to the fourth order in the Rabi couplings, we find that the Andreev current exhibits unconventional non-Ohmic transport at zero temperature. Remarkably, the Andreev current gives the only contribution in the synthetic junction system at zero detunings regardless of the ratio of the chemical potential bias to the superfluid gap, which is in sharp contrast to that in the conventional superconductor-normal metal junction. Our result may also pave a way for understanding the black hole information paradox through the Andreev reflection as a quantum-information mirror.

cond-mat.quant-gas↗

arXiv2022

Random β-transformation on fat Sierpinski gasket

We consider the iterated function system (IFS) $$f_{\vec{q}}(\vec{z})=\frac{\vec{z}+\vec{q}}β,\vec{q}\in\{(0,0),(1,0),(0,1)\}.$$ As is well known, for $β= 2$ the attractor, $S_β$, is a fractal called the Sierpiński gasket(or sieve) and for $β>2$ it is also a fractal. Our goal is to study greedy, lazy and random $β$-transformations on the attractor for this IFS with $1<β<2$. For $1<β\leq 3/2$, $S_β$ is a triangle and it is shown that the greedy transformation $T_β$ and the lazy transformation $L_β$ are isomorphic and they both admit an absolutely continuous invariant measure. We show that all $β$-expansions of a point $\vec{z}$ in $S_β$ can be generated by a random map $K_β$ defined on $\{0,1\}^\mathbb{N}\times\{0,1,2\}^\mathbb{N}\times S_β$ and $K_β$ has a unique invariant measure of maximal entropy when $1<β\leqβ_*$, where $β_*\approx 1.4656$ is the root of $x^3-x^2-1=0$. We also show existence of a $K_β$-invariant probability measure, absolutely continuous with respect to $m_1\otimes m_2 \otimes λ_2$, where $m_1, m_2$ are product measures on $\{0,1\}^\mathbb{N},\{0,1,2\}^\mathbb{N}$, respectively, and $λ_2$ is the normalized Lebesgue measure on $S_β$. For $3/2<β\leq β^*$, where $β^*\approx 1.5437$ is the root of $x^3-2x^2+2x=2$, there are radial holes in $S_β$. In this case, $K_β$ is defined on $\{0,1\}^\mathbb{N}\times S_β$. We also show that it has a unique invariant measure of maximal entropy.

math.DS↗

arXiv2019

Visibility of Cartesian products of Cantor sets

Let $K_λ$ be the attractor of the following IFS \begin{equation*} \{f_1(x)=λx, f_2(x)=λx+1-λ\}, \;\;0<λ<1/2. \end{equation*} Given $α\geq 0$, we say the line $y=αx$ is visible through $K_λ\times K_λ$ if $$ \{(x, αx): x\in \mathbb R\setminus \{0\}\}\cap ((K_λ\times K_λ))=\emptyset. $$ Let $V=\left \{α\geq 0: y=αx \mbox{ is visible through } K_λ\times K_λ \right \}$. In this paper, we give a completed description of $V$, e.g., its Hausdoff dimension and its topological property. Moreover, we also discuss another type of visible problem which is related to the slicing problem.

math.DS↗