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1.
Science ; 384(6695): 579-584, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38696580

ABSTRACT

Fractional quantum Hall (FQH) states are known for their robust topological order and possess properties that are appealing for applications in fault-tolerant quantum computing. An engineered quantum platform would provide opportunities to operate FQH states without an external magnetic field and enhance local and coherent manipulation of these exotic states. We demonstrate a lattice version of photon FQH states using a programmable on-chip platform based on photon blockade and engineering gauge fields on a two-dimensional circuit quantum electrodynamics system. We observe the effective photon Lorentz force and butterfly spectrum in the artificial gauge field, a prerequisite for FQH states. After adiabatic assembly of Laughlin FQH wave function of 1/2 filling factor from localized photons, we observe strong density correlation and chiral topological flow among the FQH photons. We then verify the unique features of FQH states in response to external fields, including the incompressibility of generating quasiparticles and the smoking-gun signature of fractional quantum Hall conductivity. Our work illustrates a route to the creation and manipulation of novel strongly correlated topological quantum matter composed of photons and opens up possibilities for fault-tolerant quantum information devices.

2.
Langmuir ; 40(9): 4852-4859, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38382061

ABSTRACT

Transition metal oxides with the merits of high theoretical capacities, natural abundance, low cost, and environmental benignity have been regarded as a promising anodic material for lithium ion batteries (LIBs). However, the severe volume expansion upon cycling and poor conductivity limit their cycling stability and rate capability. To address this issue, NiO embedded and N-doped porous carbon nanorods (NiO@NCNR) and nanotubes (NiO@NCNT) are synthesized by the metal-catalyzed graphitization and nitridization of monocrystalline Ni(II)-triazole coordinated framework and Ni(II)/melamine mixture, respectively, and the following oxidation in air. When applied as an anodic material for LIBs, the NiO@NCNR and NiO@NCNT hybrids exhibit a decent capacity of 895/832 mA h g-1 at 100 mA g-1, high rate capability of 484/467 mA h g-1 at 5.0 A g-1, and good long-term cycling stability of 663/634 mA h g-1 at 600th cycle at 1 A g-1, which are much better than those of NiO@carbon black (CB) control sample (701, 214, and 223 mA h g-1). The remarkable electrochemical properties benefit from the advanced nanoarchitecture of NiO@NCNR and NiO@NCNT, which offers a length-controlled one-dimensional porous carbon nanoarchitecture for effective e-/Li+ transport, affords a flexible carbon skeleton for spatial confinement, and forms abundant nanocavities for stress buffering and structure reinforcement during discharge/charging processes. The rational structural design and synthesis may pave a way for exploring advanced metal oxide based anodic materials for next-generation LIBs.

3.
Chem Commun (Camb) ; 59(85): 12771-12774, 2023 Oct 24.
Article in English | MEDLINE | ID: mdl-37814843

ABSTRACT

Nitrogen-doped carbon nanoribbons and nanotubes decorated with Co3O4 nanoparticles were prepared by a metal-catalyzed graphitization-nitridization and oxidization process, using triazole and melamine as a solid nitrogen/carbon co-source, and assessed as anodes of lithium ion batteries (LIBs). These composite anodes display perfect electrochemical performance, indicating their potential for application in LIBs.

4.
Sci Bull (Beijing) ; 68(15): 1625-1631, 2023 Aug 15.
Article in English | MEDLINE | ID: mdl-37453825

ABSTRACT

Complex quantum electronic circuits can be used to design noise-protected qubits, but their complexity may exceed the capabilities of classical simulation. In such cases, quantum computers are necessary for efficient simulation. In this work, we demonstrate the use of variational quantum computing on a transmon-based quantum processor to simulate a superconducting quantum electronic circuit and design a new type of qubit called "Plasmonium", which operates in the plasmon-transition regime. The fabricated Plasmonium qubits show a high two-qubit gate fidelity of 99.58(3)%, as well as a smaller physical size and larger anharmonicity compared to transmon qubits. These properties make Plasmonium a promising candidate for scaling up multi-qubit devices. Our results demonstrate the potential of using quantum computers to aid in the design of advanced quantum processors.

5.
Phys Chem Chem Phys ; 24(44): 27114-27120, 2022 Nov 18.
Article in English | MEDLINE | ID: mdl-36342075

ABSTRACT

Fe-based oxides are considered as promising anode materials for lithium-ion batteries (LIBs) due to their high theoretical capacities, low cost, natural abundance and environmental friendliness. However, their severe volume expansion upon cycling and poor conductivity limit their cycling stability and rate capability. To address this issue, a hybrid of Fe2O3 nanoparticles encapsulated at the endpoints of nitrogen-doped CNTs (Fe2O3@NCNTs) is designed and prepared using a metal-catalyzed graphitization-nitridization driven tip-growth process and subsequent oxidation in air. When evaluated as an anode material for LIBs, this Fe2O3@NCNT hybrid exhibits a high capacity of 1145 mA h g-1 at 100 mA g-1, excellent rate capability of 907 mA h g-1 at 5.0 A g-1 and remarkable cycling stability of 856 mA h g-1 after 800 cycles at 1 A g-1, which are much superior to those of the Fe2O3/carbon black (CB) control material. The outstanding electrochemical performance benefits from the unique nanoarchitecture of Fe2O3@NCNTs, which provides a porous conductive matrix for effective electron-ion transport, and provides space confining carbon nanocaps as well as stress buffer nanocavities for robust structural stability during the lithiation/delithiation process. The results may pave the way for the rational structural design of high-performance metal oxide-based anode materials for next-generation LIBs.

6.
Phys Rev Lett ; 128(25): 250401, 2022 Jun 24.
Article in English | MEDLINE | ID: mdl-35802432

ABSTRACT

First proposed by Mayers and Yao, self-testing provides a certification method to infer the underlying physics of quantum experiments in a black-box scenario. Numerous demonstrations have been reported to self-test various types of entangled states. However, all the multiparticle self-testing experiments reported so far suffer from both detection and locality loopholes. Here, we report the first experimental realization of multiparticle entanglement self-testing closing the locality loophole in a photonic system, and the detection loophole in a superconducting system, respectively. We certify three-party and four-party GHZ states with at least 0.84(1) and 0.86(3) fidelities in a device-independent way. These results can be viewed as a meaningful advance in multiparticle loophole-free self-testing, and also significant progress on the foundations of quantum entanglement certification.

7.
Phys Rev Lett ; 128(4): 040403, 2022 Jan 28.
Article in English | MEDLINE | ID: mdl-35148136

ABSTRACT

Standard quantum theory was formulated with complex-valued Schrödinger equations, wave functions, operators, and Hilbert spaces. Previous work attempted to simulate quantum systems using only real numbers by exploiting an enlarged Hilbert space. A fundamental question arises: are the complex numbers really necessary in the standard formalism of quantum theory? To answer this question, a quantum game has been developed to distinguish standard quantum theory from its real-number analog, by revealing a contradiction between a high-fidelity multiqubit quantum experiment and players using only real-number quantum theory. Here, using superconducting qubits, we faithfully realize the quantum game based on deterministic entanglement swapping with a state-of-the-art fidelity of 0.952. Our experimental results violate the real-number bound of 7.66 by 43 standard deviations. Our results disprove the real-number formulation and establish the indispensable role of complex numbers in the standard quantum theory.

8.
Behav Brain Res ; 347: 436-445, 2018 07 16.
Article in English | MEDLINE | ID: mdl-29580890

ABSTRACT

Increased proinflammatory cytokines, such as interleukin (IL)-1ß, may play an important role in the etiology of depression because they cause the hypothalamic-pituitary-adrenal axis to release glucocorticoids (GC) and induce dysfunction of serotonin and norepinephrine neurotransmission. Sustained increase in GC may activate microglia to induce neuroinflammation, and suppress astrocytes to produce neurotrophins, which lead to neuronal apoptosis. Here, we tested the hypothesis that glucocorticoid receptor (GR) antagonist mifepristone (RU486) may attenuate IL-1ß-induced depression-like behavior by regulating the neuroinflammation and neurotrophin functions of microglia and astrocytes. Rats received intracerebroventricular injections of IL-1ß (10 ng) and/or subcutaneous injections of RU486 for 14 days. Then animal depression-like behaviors, serum corticosterone concentration, the levels of pro-inflammatory cytokines (TNF-α, IL-6), mRNA and protein expressions of CD11b, GFAP and neurotrophins (pro-BDNF, BDNF, GDNF and their receptors TrkB, p75, GFRα-1 and GFRα-2) in the amygdala were studied. Compared to controls, significantly decreased rearing score and increased defecation in the open field test, decreases in ratio of open/closed time in the elevated plus maze and in sucrose preference, while increased level of corticosterone in the serum were found in the rats administrated with IL-1ß. IL-1ß administration also reduced the expressions of GFAP, BDNF, GDNF and its receptor GFR-α1, but increased the expressions of CD11b, pro-BDNF, p75 and pro-inflammatory cytokines (TNF-α, IL-6) concentrations. RU486 treatment markedly attenuated these changes induced by IL-1ß, except for the expressions of GFR-α1. In conclusion, RU486 may improve depression-like changes by suppressing microglia and inflammation and promoting astrocytes to restore neurotrophin function.


Subject(s)
Antidepressive Agents/pharmacology , Depressive Disorder/drug therapy , Depressive Disorder/immunology , Interleukin-1beta/metabolism , Mifepristone/pharmacology , Amygdala/drug effects , Amygdala/metabolism , Anhedonia/drug effects , Anhedonia/physiology , Animals , Corticosterone/blood , Disease Models, Animal , Hormone Antagonists/pharmacology , Interleukin-1beta/administration & dosage , Male , Motor Activity/drug effects , Motor Activity/physiology , Nerve Growth Factors/metabolism , RNA, Messenger/metabolism , Rats, Sprague-Dawley , Receptors, Glucocorticoid/antagonists & inhibitors , Receptors, Glucocorticoid/metabolism , Recombinant Proteins/administration & dosage
9.
Zhongguo Zhong Yao Za Zhi ; 33(9): 1060-3, 2008 May.
Article in Chinese | MEDLINE | ID: mdl-18652358

ABSTRACT

OBJECTIVE: To study the mechanisms of the anti-myocardial ischemia of total flavones of Hippophae rhamnoides (TFH) at the level of proteome. METHOD: Surface enhanced laser desorption/ionization (SELDI) mass spectrometry with protein chip IMAC3, SAX2 and NP20 was performed to compare the differentially expressed protein in myocardial ischemia in the TFH-treated groups with the 0.9% sodium chloride groups. Protein chips were examined in PBS II - C protein chip reader (ciphergen ciosystem inc) and the protein profiling was analyzed by Proteinchip Software 3. 0. 2. RESULT: The revealed six peaks had significant difference between the TFH-treated groups and the control groups, one of which were up-regulated in the TFH-treated groups, and the other were down-regulated. And in these six distinct proteins, there were four proteins on the IMAC3 chips and one protein on the SAX2 chips. CONCLUSION: The TFH could prevent the myocardium from ischemia via regulating expression of different proteins.


Subject(s)
Drugs, Chinese Herbal/pharmacology , Flavones/pharmacology , Heart/drug effects , Hippophae/chemistry , Proteomics/methods , Animals , Female , Flavones/chemistry , Male , Myocardial Ischemia/prevention & control , Random Allocation , Rats , Rats, Wistar , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
10.
Faraday Discuss ; 132: 269-80; discussion 309-19, 2006.
Article in English | MEDLINE | ID: mdl-16833122

ABSTRACT

Surface Enhanced Raman Scattering (SERS) gives rise to analytical applications with much promise. In our approach three steps are necessary. We require a SERS platform of high enhancement. This has been achieved using the special technique of Island Lithography, combined with Ag deposition by galvanic exchange, yielding an enhancement factor of 10(8). Probe oligonucleotide molecules are attached to a specific area on the platform, at the optimized surface concentration, using thiolated single stranded (ss) DNA molecules. The optimum surface concentration has been determined and interpreted in the light of the polyelectrolyte behaviour of ssDNA. Finally the change in SERS produced by hybridisation of the probe molecules to a target DNA molecule is measured. Highly discernible changes have been obtained. No change in probe signal is seen when presented with one base mismatched target. From this work it is concluded that the prospects for label-free DNA detection in high-density arrays is now close to achievement.


Subject(s)
Oligonucleotide Array Sequence Analysis/methods , Spectrum Analysis, Raman/methods , Adsorption , Nucleic Acid Hybridization , Surface Properties
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