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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., Comment: 13 pages, 7 figures

Evolutionary multitasking (EMT) has emerged as a popular topic of evolutionary computation over the past years. 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 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 optimization platform, named MTO-Platform (MToP), for EMT. MToP incorporates over 40 MTEAs, more than 150 MTO problem cases with real-world applications, and over 10 performance metrics. Moreover, to facilitate comparative analyses between MTEAs and traditional evolutionary algorithms, we adapted over 40 popular single-task evolutionary algorithms to address MTO problems. MToP boasts a user-friendly graphical interface, facilitating results analysis, data export, and schematics 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.

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., Comment: 6 pages, 4 figures

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., Comment: 9 pages, 6 figures

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-{\gamma}, TNF-{\alpha} 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., Comment: 25 pages, 6 figures

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., Comment: 7 pages, 5 figures

We consider the iterated function system (IFS) $$f_{\vec{q}}(\vec{z})=\frac{\vec{z}+\vec{q}}{\beta},\vec{q}\in\{(0,0),(1,0),(0,1)\}.$$ As is well known, for $\beta = 2$ the attractor, $S_\beta$, is a fractal called the Sierpi\'nski gasket(or sieve) and for $\beta>2$ it is also a fractal. Our goal is to study greedy, lazy and random $\beta$-transformations on the attractor for this IFS with $1<\beta<2$. For $1<\beta\leq 3/2$, $S_\beta$ is a triangle and it is shown that the greedy transformation $T_\beta$ and the lazy transformation $L_\beta$ are isomorphic and they both admit an absolutely continuous invariant measure. We show that all $\beta$-expansions of a point $\vec{z}$ in $S_\beta$ can be generated by a random map $K_\beta$ defined on $\{0,1\}^\mathbb{N}\times\{0,1,2\}^\mathbb{N}\times S_\beta$ and $K_\beta$ has a unique invariant measure of maximal entropy when $1<\beta\leq\beta_*$, where $\beta_*\approx 1.4656$ is the root of $x^3-x^2-1=0$. We also show existence of a $K_\beta$-invariant probability measure, absolutely continuous with respect to $m_1\otimes m_2 \otimes \lambda_2$, where $m_1, m_2$ are product measures on $\{0,1\}^\mathbb{N},\{0,1,2\}^\mathbb{N}$, respectively, and $\lambda_2$ is the normalized Lebesgue measure on $S_\beta$. For $3/2<\beta\leq \beta^*$, where $\beta^*\approx 1.5437$ is the root of $x^3-2x^2+2x=2$, there are radial holes in $S_\beta$. In this case, $K_\beta$ is defined on $\{0,1\}^\mathbb{N}\times S_\beta$. We also show that it has a unique invariant measure of maximal entropy.

Let $K_{\lambda}$ be the attractor of the following IFS \begin{equation*} \{f_1(x)=\lambda x, f_2(x)=\lambda x+1-\lambda\}, \;\;0<\lambda<1/2. \end{equation*} Given $\alpha \geq 0$, we say the line $y=\alpha x$ is visible through $K_{\lambda}\times K_{\lambda}$ if $$ \{(x, \alpha x): x\in \mathbb R\setminus \{0\}\}\cap ((K_{\lambda}\times K_{\lambda}))=\emptyset. $$ Let $V=\left \{\alpha \geq 0: y=\alpha x \mbox{ is visible through } K_{\lambda}\times K_{\lambda} \right \}$. 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., Comment: 13 pages