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1.
Opt Express ; 32(1): 722-741, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38175094

RESUMO

We propose a mechanism to simultaneously enhance quantum cooling and entanglement via coupling an auxiliary microwave cavity to a magnomechanical cavity. The auxiliary cavity acts as a dissipative cold reservoir that can efficiently cool multiple localized modes in the primary system via beam-splitter interactions, which enables us to obtain strong quantum cooling and entanglement. We analyze the stability of the system and determine the optimal parameter regime for cooling and entanglement under the auxiliary-microwave-cavity-assisted (AMCA) scheme. The maximum cooling enhancement rate of the magnon mode can reach 98.53%, which clearly reveals that the magnomechanical cooling is significantly improved in the presence of the AMCA. More importantly, the dual-mode entanglement of the system can also be significantly enhanced by AMCA in the full parameter region, where the initial magnon-phonon entanglement can be maximally enhanced by a factor of about 11. Another important result of the AMCA is that it also increases the robustness of the entanglement against temperature. Our approach provides a promising platform for the experimental realization of entanglement and quantum information processing based on cavity magnomechanics.

2.
Opt Express ; 32(4): 6658-6671, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439364

RESUMO

By effectively controlling the dipole-dipole interaction, we investigate the characteristics of the ground state of bright solitons in a spin-orbit coupled dipolar Bose-Einstein condensate. The dipolar atoms are trapped within a double-lattice which consists of a linear and a nonlinear lattice. We derive the motion equations of the different spin components, taking the controlling mechanisms of the dipole-dipole interaction into account. An analytical expression of dipole-dipole interaction is derived. By adjusting the dipole polarization angle, the dipole interaction can be adjusted from attraction to repulsion. On this basis, we study the generation and manipulation of the bright solitons using both the analytical variational method and numerical imaginary time evolution. The stability of the bright solitons is also analyzed and we map out the stability phase diagram. By adjusting the long-range dipole-dipole interaction, one can achieve manipulation of bright solitons in all aspects, including the existence, width, nodes, and stability. Considering the complexity of our system, our results will have enormous potential applications in quantum simulation of complex systems.

3.
Phys Rev Lett ; 132(12): 126201, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38579216

RESUMO

The competition between on-site electronic correlation and local crystal field stands out as a captivating topic in research. However, its physical ramifications often get overshadowed by influences of strong periodic potential and orbital hybridization. The present study reveals this competition may become more pronounced or even dominant in two-dimensional systems, driven by the combined effects of dimensional confinement and orbital anisotropy. This leads to electronic orbital reconstruction in certain perovskite superlattices or thin films. To explore the emerging physics, we investigate the interfacial orbital disorder-order transition with an effective Hamiltonian and how to modulate this transition through strains.

4.
Opt Express ; 31(4): 6566-6576, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36823909

RESUMO

In this work, we investigated the effect of 2 MeV proton irradiation on the performance of InAs/GaSb type-II superlattice long-wave infrared detectors by combining ground-based irradiation experiments with Stopping and Range of Ions in Matter (SRIM) computer simulations. We found that irradiation with 2 MeV protons significantly increases the dark current density of the detector by more than two orders of magnitude. At the same time, the quantum efficiency decreases by an order of magnitude. Moreover, proton irradiation degrades the device's performance by raising bulk and surface leakage currents. As the mesa size of the device increases, the proportion of surface leakage current in the total dark current drops. When the mesa size is smaller, the detector irradiation damage is greater. In addition, simulations indicate that the amount of damage produced by 2 MeV proton irradiation rises as irradiation fluences increase. The trends of the irradiation damage produced by the SRIM simulation results and the photocurrent measurements after proton irradiation are consistent, whereas the dark current measurements are identical only at small fluences.

5.
Opt Express ; 31(7): 11116-11131, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37155754

RESUMO

We propose a physical scheme to study the formation of optical soliton molecules (SMs), consisting of two solitons bound together with a π-phase difference, and the scattering of SMs by a localized parity-time (P T)-symmetric potential. In order to stabilize SMs, we apply an additional space-dependent magnetic field to introduce a harmonic trapping potential for the two solitons and balance the repulse interaction induced by the π-phase difference between them. On the other hand, a localized complex optical potential obeying P T symmetry can be created through an incoherent pumping and spatial modulation of the control laser field. We investigate the scattering of optical SMs by the localized P T-symmetric potential, which exhibits evident asymmetric behavior and can be actively controlled by changing the incident velocity of SMs. Moreover, the P T symmetry of the localized potential, together with the interaction between two solitons of the SM, can also have a significant effect on the SM scattering behavior. The results presented here may be useful for understanding the unique properties of SMs and have potential applications in optical information processing and transmission.

6.
Opt Express ; 29(22): 35022-35037, 2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34808947

RESUMO

When the input colors of the left and right eyes are different from one another, binocular rivalry may occur. According to Hering theory, opponent colors would have the most significant tendency for rivalry. However, binocular color fusion still occurs under the condition that each eye's opponent chromatic responses do not exceed a specific chromatic fusion limit (CFL). This paper detects the binocular chromatic fusion limit for opposite colors within a conventional 3D display color gamut. We conducted a psychophysical experiment to quantitatively measure the binocular chromatic fusion limit on four opposite color directions in the CIELAB color space. Due to color inconsistency between eyes may affect the binocular color fusion, the experiment was divided into two sessions by swapping stimulation colors of left and right eyes. There were 5 subjects and they each experienced 320 trials. By analyzing the results, we used ellipses to quantify the chromatic fusion limits for opposing colors. The average semi-major axis of the ellipses is 27.55 Δ E a b∗, and the average semi-minor axis is 16.98 Δ E a b∗. We observed that the chromatic fusion limit varies with the opposite color direction: the CFL on RedBlue-GreenYellow direction is greater than that on Red-Green direction, the latter being greater than that on Yellow-Blue direction and the CFL on RedYellow-GreenBlue direction is smallest. Furthermore, we suggested that the chromatic fusion limit is independent of the distribution of cells, and there is no significant change in the fusion ellipse boundaries after swapping left and right eye colors.


Assuntos
Percepção de Cores/fisiologia , Visão Binocular/fisiologia , Adulto , Desenho de Equipamento , Humanos , Imageamento Tridimensional , Psicofísica , Disparidade Visual/fisiologia , Visão Ocular/fisiologia , Córtex Visual/fisiologia , Adulto Jovem
7.
Nonlinear Dyn ; 106(2): 1187-1195, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33867677

RESUMO

The extensive proliferation of recent coronavirus (COVID-19), all over the world, is the outcome of social interactions through massive transportation, gatherings and population growth. To disrupt the widespread of COVID-19, a mechanism for social distancing is indispensable. Also, to predict the effectiveness and quantity of social distancing for a particular social network, with a certain contagion, a generalized model is needed. In this manuscript, we propose a social distancing mediated generalized model to predict the pandemic spread of COVID-19. By considering growth rate as a temporal harmonic function damped with social distancing in generalized Richard model and by using the data of confirmed COVID-19 cases in China, USA and India, we find that, with time, the cumulative spread grows more rapidly due to weak social distancing as compared to the stronger social distancing, where it is explicitly decreasing. Furthermore, we predict the possible outcomes with various social distancing scenarios by considering highest growth rate as an initial state, and illustrate that the increase in social distancing tremendously decreases growth rate, even it tends to reach zero in lockdown regimes. Our findings not only provide epidemic growth scenarios as a function of social distancing but also provide a modified growth model to predict controlled information flow in any network.

8.
Phys Rev Lett ; 125(5): 050402, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32794842

RESUMO

We demonstrate the existence of finite-component multicriticality in a qubit-boson model where biased qubits collectively coupled to a single-mode bosonic field. The interplay between biases and boson-qubit coupling produces a rich phase diagram which shows multiple superradiant phases and phase boundaries of different orders. In particular, multiple phases become indistinguishable in appropriate bias configurations, which is the signature of multicriticality. A series of universality classes characterizing these multicritical points are identified. Moreover, we present a trapped-ion realization with the potential to explore multicritical phenomena experimentally using a small number of ions. The results open a novel way to probe multicritical universality classes in experiments.

9.
Phys Rev Lett ; 121(22): 220403, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30547620

RESUMO

We investigate the universal dissipationless dynamics of Gaussian continuous-variable systems in the presence of a band-gapped bosonic environment. Our results show that environmental band gaps can induce localized modes, which give rise to the dissipationless dynamics where the system behaves as free oscillators instead of experiencing a full decay in the long-time limit. We present a complete characterization of localized modes and show the existence of the critical system-environment coupling. Beyond the critical values, localized modes can be produced, and the system dynamics become dissipationless. This novel dynamics can be utilized to overcome the environmental noises and protect the quantum resources in the continuous-variable quantum information.

10.
Phys Rev E ; 109(5-1): 054132, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38907473

RESUMO

One of the main challenges in developing high-performance quantum batteries is the self-discharging process, where energy is dissipated from a quantum battery into the environment. In this work, we investigate the influence of non-Markovian noises on the performance of a quantum battery. Our results demonstrate that adding auxiliary qubits to a quantum battery system can effectively suppress the self-discharging process, leading to an improvement in both the steady-state energy and extractable work. We reveal that the physical mechanism inhibiting the self-discharging process is the formation of system-environment bound states, rather than an increase in non-Markovianity. Our results could be of both theoretical and experimental interest in exploring the ability of quantum batteries to maintain long stored energy in the environment.

11.
World J Gastroenterol ; 30(7): 728-741, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515944

RESUMO

BACKGROUND: Liver injury is common in severe acute pancreatitis (SAP). Excessive autophagy often leads to an imbalance of homeostasis in hepatocytes, which induces lipid peroxidation and mitochondrial iron deposition and ultimately leads to ferroptosis. Our previous study found that milk fat globule epidermal growth factor 8 (MFG-E8) alleviates acinar cell damage during SAP via binding to αvß3/5 integrins. MFG-E8 also seems to mitigate pancreatic fibrosis via inhibiting chaperone-mediated autophagy. AIM: To speculate whether MFG-E8 could also alleviate SAP induced liver injury by restoring the abnormal autophagy flux. METHODS: SAP was induced in mice by 2 hly intraperitoneal injections of 4.0 g/kg L-arginine or 7 hly injections of 50 µg/kg cerulein plus lipopolysaccharide. mfge8-knockout mice were used to study the effect of MFG-E8 deficiency on SAP-induced liver injury. Cilengitide, a specific αvß3/5 integrin inhibitor, was used to investigate the possible mechanism of MFG-E8. RESULTS: The results showed that MFG-E8 deficiency aggravated SAP-induced liver injury in mice, enhanced autophagy flux in hepatocyte, and worsened the degree of ferroptosis. Exogenous MFG-E8 reduced SAP-induced liver injury in a dose-dependent manner. Mechanistically, MFG-E8 mitigated excessive autophagy and inhibited ferroptosis in liver cells. Cilengitide abolished MFG-E8's beneficial effects in SAP-induced liver injury. CONCLUSION: MFG-E8 acts as an endogenous protective mediator in SAP-induced liver injury. MFG-E8 alleviates the excessive autophagy and inhibits ferroptosis in hepatocytes by binding to integrin αVß3/5.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Ferroptose , Glicolipídeos , Glicoproteínas , Gotículas Lipídicas , Pancreatite , Camundongos , Animais , Fator VIII , Pancreatite/induzido quimicamente , Pancreatite/complicações , Doença Aguda , Hepatócitos/metabolismo , Autofagia , Família de Proteínas EGF , Proteínas do Leite/metabolismo , Proteínas do Leite/farmacologia
12.
Eur J Pharmacol ; 969: 176462, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38431242

RESUMO

Pancreatic cancer is an extremely malignant tumor, and only a few clinical treatment options exist. MFG-E8 and kindlin-2 all play an important role in cancer progression. However, the specific mechanism occurring between MFG-E8, kindlin-2 and the migration and invasion of pancreatic cancer cells remains unelucidated. To unravel the specific mechanism, this study assessed the potential association between MFG-E8 and kindlin-2 as well as the involvement of MFG-E8 in pancreatic cancer using two pancreatic cancer cell lines (MiaPaCa-2 and PANC-1). Pancreatic cancer cells were treated with 0, 250, and 500 ng/ml MFG-E8, and the effects of MFG-E8 on the migration, invasion, and anoikis of pancreatic cancer cells were observed. To investigate the role of kindlin-2 in pancreatic cancer, kindlin-2-shRNAi was transfected to knock down its expression level in the two pancreatic cancer cell lines. Furthermore, cilengitide, a receptor blocker of MFG-E8, was used to explore the relationship between MFG-E8, kindlin-2, and pancreatic cancer progression. Our findings demonstrated that MFG-E8 promotes the migration and invasion of pancreatic cancer cells and induces cell anoikis resistance in a dose-dependent manner, which was effectively counteracted by cilengitide, a receptor blocker. Additionally, the knockdown of kindlin-2 expression nullified the effect of MFG-E8 on the migration and invasion of pancreatic cancer cells. Consequently, this study provides insights into the specific mechanism underlying the interplay between MFG-E8 and kindlin-2 in the progression of pancreatic cancer cells.


Assuntos
Anoikis , Neoplasias Pancreáticas , Humanos , Linhagem Celular , Pâncreas , Neoplasias Pancreáticas/genética , Transição Epitelial-Mesenquimal
13.
Cell Death Discov ; 10(1): 156, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538578

RESUMO

Acute pancreatitis (AP) continues to pose a major challenge as targeted therapeutic interventions are absent. Mitochondrial dysfunction and inflammasome-dependent pyroptosis are involved in the pathogenic mechanisms of AP. CIRP is a stress-response protein and a damage-associated molecular pattern (DAMP) molecule. In our previous studies, we discovered that excessive CIRP can directly damage pancreatic acinar cells. Nonetheless, the precise involvement of CIRP in AP is still unexplored. The primary aim of this study was to examine the potential involvement of CIRP in the development of pyroptosis and mitochondrial dysfunction in AP. To study this, an L-arginine-induced AP mouse model was used. Our results showed that Caspase-1-mediated pyroptosis and mitochondria-derived reactive oxygen species (ROS) were crucial factors in the occurrence of tissue damage and inflammation in AP. A substantial increase in the CIRP serum levels was observed in AP mice. Blocking CIRP by either CIRP gene knockout or systemic administration of C23, a competing inhibitor of CIRP, reduced ROS accumulation and pyroptosis in AP mice. These effects were associated with attenuated pancreatic injury and inflammation. In addition, CIRP-triggered mitochondrial dysfunction, autophagy impairment, and pyroptosis in pancreatic acinar cells were prevented by TAK242, an inhibitor of CIRP receptor TLR4. In conclusion, CIRP can induce mitochondrial dysfunction and pyroptosis in pancreatic acinar cells, and blocking CIRP may be a valuable approach to treating patients with AP.

14.
Phys Rev Lett ; 110(9): 090402, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23496692

RESUMO

We study an optical cavity coupled to a lattice of Rydberg atoms, which can be represented by a generalized Dicke model. We show that the competition between the atom-atom interaction and atom-light coupling induces a rich phase diagram. A novel superradiant solid (SRS) phase is found, where both the superradiance and crystalline orders coexist. Different from the normal second order superradiance transition, here both the solid-1/2 and SRS to SR phase transitions are first order. These results are confirmed by large scale quantum Monte Carlo simulations.

15.
Sci Rep ; 13(1): 21085, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38030714

RESUMO

Recently, a possible room-temperature superconductor known as LK-99 (Pb10-xCux(PO4)6O (0.9 < x < 1.1)) has sparked a wave of research. However, many experimental works have proven that it is a semiconductor. At the same time, many theoretical works have reached the conclusion that it is a flat band metal. The inconsistency between theoretical and experimental works may be caused by neglecting the spin-orbit coupling effect in calculations. We performed calculations of electronic structure of Pb9Cu(PO4)6O with spin-orbit coupling, and the results show that it's indeed a semiconductor, not a metal. In the ferromagnetic state it is an indirect-bandgap semiconductor with a bandgap of 292 meV. While in the antiferromagnetic-A state, it is a direct-bandgap semiconductor with a bandgap of 300 meV. Our work provides a possible explanation for the contradictions of previous experiments and theories, and provides some theoretical basis for the potential application of Pb9Cu(PO4)6O as a semiconductor.

16.
Nanomaterials (Basel) ; 13(24)2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38133038

RESUMO

Anisotropic plasmonic metasurfaces have attracted broad research interest since they possess novel optical properties superior to natural materials and their tremendous design flexibility. However, the realization of multi-wavelength selective plasmonic metasurfaces that have emerged as promising candidates to uncover multichannel optical devices remains a challenge associated with weak modulation depths and narrow operation bandwidth. Herein, we propose and numerically demonstrate near-infrared multi-wavelength selective passive plasmonic switching (PPS) that encompasses high ON/OFF ratios and strong modulation depths via multiple Fano resonances (FRs) in anisotropic plasmonic metasurfaces. Specifically, the double FRs can be fulfilled and dedicated to establishing tailorable near-infrared dual-wavelength PPS. The multiple FRs mediated by in-plane mirror asymmetries cause the emergence of triple-wavelength PPS, whereas the multiple FRs governed by in-plane rotational asymmetries avail the implementation of the quasi-bound states in the continuum-endowed multi-wavelength PPS with the ability to unfold a tunable broad bandwidth. In addition, the strong polarization effects with in-plane anisotropic properties further validate the existence of the polarization-resolved multi-wavelength PPS. Our results provide an alternative approach to foster the achievement of multifunctional meta-devices in optical communication and information processing.

17.
Science ; 380(6652): 1367-1372, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37384701

RESUMO

Rydberg excitons, the solid-state counterparts of Rydberg atoms, have sparked considerable interest with regard to the harnessing of their quantum application potentials, but realizing their spatial confinement and manipulation poses a major challenge. Lately, the rise of two-dimensional moiré superlattices with highly tunable periodic potentials provides a possible pathway. Here, we experimentally demonstrate this capability through the spectroscopic evidence of Rydberg moiré excitons (XRM), which are moiré-trapped Rydberg excitons in monolayer semiconductor tungsten diselenide adjacent to twisted bilayer graphene. In the strong coupling regime, the XRM manifest as multiple energy splittings, pronounced red shift, and narrowed linewidth in the reflectance spectra, highlighting their charge-transfer character wherein electron-hole separation is enforced by strongly asymmetric interlayer Coulomb interactions. Our findings establish the excitonic Rydberg states as candidates for exploitation in quantum technologies.

18.
Cell Biosci ; 13(1): 64, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36964632

RESUMO

BACKGROUND: Endoplasmic reticulum (ER) stress plays an important role in the occurrence and development of various liver diseases. However, there are no effective prevention and treatment strategies. We aimed to determine the role of heat shock factor 2 binding protein (HSF2BP) in ER stress. METHODS: HSF2BP expression in mice and cultured hepatocytes was measured during ER stress induced by tunicamycin, and its importance in ER stress was evaluated in hepatocyte-specific HSF2BP transgenic (TG) and knockout (KO) mice. The effects and mechanisms of HSF2BP on ER stress were further probed in hepatic ischemia-reperfusion (I/R) injury. RESULTS: HSF2BP expression was significantly upregulated during tunicamycin-induced ER stress in mice and cultured hepatocytes. Liver injury and ER stress were reduced in HSF2BP overexpressing mice after treating with tunicamycin, but were aggravated in HSF2BP knockout mice compared to the controls. In hepatic I/R injury, HSF2BP expression was significantly upregulated, and HSF2BP overexpressing mice had reduced liver injury and inflammation. These improvements were associated with ER stress inhibition. However, these results were reversed in hepatocyte-specific HSF2BP knockout mice. HSF2BP overexpression increased cytoplasmic CDC73 levels and inhibited the JNK signaling pathway. CDC73 knockdown using siRNA eliminated the protection exerted by HSF2BP overexpression in hypoxia/reoxygenation (H/R)-induced ER stress in hepatocytes. CONCLUSION: HSF2BP is a previously uncharacterized regulatory factor in ER stress-likely acts by regulating CDC73 subcellular localization. The feasibility of HSF2BP-targeted treatment in ER stress-related liver disease deserves future research.

19.
iScience ; 26(7): 107043, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37360693

RESUMO

Severe acute pancreatitis (AP) is associated with a high mortality rate. Cold-inducible RNA binding protein (CIRP) can be released from cells in inflammatory conditions and extracellular CIRP acts as a damage-associated molecular pattern. This study aims to explore the role of CIRP in the pathogenesis of AP and evaluate the therapeutic potential of targeting extracellular CIRP with X-aptamers. Our results showed that serum CIRP concentrations were significantly increased in AP mice. Recombinant CIRP triggered mitochondrial injury and ER stress in pancreatic acinar cells. CIRP-/- mice suffered less severe pancreatic injury and inflammatory responses. Using a bead-based X-aptamer library, we identified an X-aptamer that specifically binds to CIRP (XA-CIRP). Structurally, XA-CIRP blocked the interaction between CIRP and TLR4. Functionally, it reduced CIRP-induced pancreatic acinar cell injury in vitro and L-arginine-induced pancreatic injury and inflammation in vivo. Thus, targeting extracellular CIRP with X-aptamers may be a promising strategy to treat AP.

20.
Adv Mater ; 35(32): e2301339, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37308132

RESUMO

Heat current in ferromagnets can generate a transverse electric voltage perpendicular to magnetization, known as anomalous Nernst effect (ANE). ANE originates intrinsically from the combination of large Berry curvature and density of states near the Fermi energy. It shows technical advantages over the conventional longitudinal Seebeck effect in converting waste heat to electricity due to its unique transverse geometry. However, materials showing giant ANE remain to be explored. Herein,  a large ANE thermopower of Syx ≈ 2 µV K-1 at room temperature in ferromagnetic Fe3 Pt epitaxial films is reported, which also show a giant transverse thermoelectric conductivity of αyx ≈ 4 A K-1  m-1 and a remarkable coercive field of 1300 Oe. The theoretical analysis reveals that the strong spin-orbit interaction in addition to the hybridization between Pt 5d and Fe 3d electrons leads to a series of distinct energy gaps and large Berry curvature in the Brillouin zone, which is the key for the large ANE. These results highlight the important roles of both Berry curvature and spin-orbit coupling in achieving large ANE at zero magnetic field, providing pathways to explore materials with giant transverse thermoelectric effect without an external magnetic field.

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