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Y. F. Li

Publications and source records attributed to Y. F. Li.

At least 19 recordsLinked to original sources

Amplification of Weak Forces via Parametric Interactions and Non-Markovian Effects in Cavity Optomechanics

Weak force amplification describes the process of amplifying a faint low-frequency signal by means of an additional high-frequency modulation, which plays a vital role in quantum sensing and high-precision measurement. However, the potential enhancement of weak-force amplification in non-Markovian environments has received little attention. In this paper, we firstly study the amplification of weak forces within cavity-optomechanical systems incorporating a degenerate optical parametric amplifier (DOPA) under the Markovian assumption. The results show that the weak force can be effectively amplified by using two high-frequency signals via vibrational resonance through adjusting the strength and phase of the DOPA with different pumping frequencies. Moreover, we extend the study of the amplification of the weak force to the non-Markovian environment which consists of a collection of infinite oscillators. We illustrate that the amplification exhibits a conversion from the non-Markovian regime to Markovian regime by controlling environmental spectral width. This conversion leads to enhancements of amplification, which originates from the excitation backflow obtained through the interaction between the cavity and non-Markovian environment. By controlling DOPA to amplify weak forces, the study achieves amplification in the non-Markovian regime, offering new directions for quantum optics research.

physics.optics

Inverse design of exceptional points in a single-resonance two-port network

Exceptional points (EPs) in non-Hermitian photonic systems enable unconventional control of wave amplitude and phase. However, identifying the EPs in a multidimensional parameter space of a system can be nontrivial and, in some cases, even infeasible. Here we propose an inverse-design method to efficiently locate the scattering EPs for a two-port resonant system supporting a single mode. The proposed method provides a direct way for tuning of geometric parameters to realize scattering EPs, as confirmed by both full-wave simulation and equivalent circuit model. In principle, our method is compatible with multi-mode system and applicable to a broad class of resonant systems.

physics.optics

Switchable coherent state stored quantum batteries with large ergotropies

Quantum battery (QB) is a conceptually new energy storage and conversion device, which consists usually of a quantum charger and an energy store (called usually as the QB for simplicity). The demonstrated advantage of QB, over its classical counterpart, is that its charging efficiency can be significantly enhanced by using quantum entanglement resources. In this letter, we investigate alternatively how to realize the switchable charging and the lossless power detection of the charged QB. With the proposed QB configuration we show that, by adjusting the eigenfrequency of the qubit-based charger, the cavity-based QB can be switched on between the charging and power-off states and its stored energy can be non-destructively monitored by probing the transmitted spectrum of the external electromagnetic waves scattered by the qubit-based charger. As the qubit-based charger has never been excited, the proposed cavity-based QB could directly store the coherent state energy (rather than the single-photon one) and thus possess significantly large ergotropy. The physical realization of the proposed switchable QB configuration is demonstrated specifically with the experimental circuit quantum electrodynamical devices.

quant-ph

Comprehensive Measurement of the Reactor Antineutrino Spectrum and Flux at Daya Bay

This Letter reports the precise measurement of reactor antineutrino spectrum and flux based on the full data set of 4.7 million inverse-beta-decay (IBD) candidates collected at Daya Bay near detectors. Expressed in terms of the IBD yield per fission, the antineutrino spectra from all reactor fissile isotopes and the specific $\mathrm{^{235}U}$ and $\mathrm{^{239}Pu}$ isotopes are measured with 1.3$\%$, 3$\%$ and 8$\%$ uncertainties respectively near the 3 MeV spectrum peak in reconstructed energy, reaching the best precision in the world. The total antineutrino flux and isotopic $\mathrm{^{235}U}$ and $\mathrm{^{239}Pu}$ fluxes are precisely measured to be $5.84\pm0.07$, $6.16\pm0.12$ and $4.16\pm0.21$ in units of $10^{-43} \mathrm{cm^2/fission}$. These measurements are compared with the Huber-Mueller (HM) model, the reevaluated conversion model based on the Kurchatov Institute (KI) measurement and the latest Summation Model (SM2023). The Daya Bay flux shows good consistency with KI and SM2023 models, but disagrees with HM model. The Daya Bay spectrum, however, disagrees with all model predictions.

nucl-ex

Dressed bound states and non-Markovian dynamics with a whispering-gallery-mode microcavity coupled to a two-level atom and a semi-infinite photonic waveguide

We investigate the dressed bound states (DBS) in an open cavity with a whispering-gallery-mode microring coupled to a two-level atom and a waveguide with a mirror at the right end. We demonstrate that the non-Hermiticity of an open cavity facilitates the formation of the DBS, which consists of the vacancy-like DBS and Friedrich-Wintgen DBS. By deriving analytical conditions for these DBS, we show that when a two-level atom couples to the standing-wave mode that corresponds to a node of the photonic wave function the vacancy-like DBS occur, which are characterized by null spectral density at cavity resonance. Conversely, Friedrich-Wintgen DBS can be realized by continuously adjusting system parameters and indicated by the disappearance of the Rabi peak in the emission spectrum, which is a distinctive feature in the strong-coupling regime. Moreover, we extend our analysis to the non-Markovian regime and find that our results are consistent with those obtained under the Markovian approximation in the wideband limit. In the non-Markovian regime, we analyze DBS for both zero and non-zero accumulated phase factors. For zero accumulated phase factors, the non-Markovian regime exhibits higher peak values and longer relaxation times for vacancy-like DBS compared to the Markovian regime, where the Friedrich-Wintgen DBS are absent in the non-Markovian case. Finally, we establish the correspondence between the energy spectrum and bound state conditions for non-zero accumulated phase factors and analyze the influence of various parameters on non-Markovian bound states. Our work exhibits bound state manipulations through non-Markovian open quantum system, which holds great potential for building high-performance quantum devices for applications such as sensing, photon storage, and nonclassical light generation.

physics.optics

Quantum detection of millimeter wave electric fields with driving surface-state electrons

We introduce a spin-based receiver to sensitively detect the electric fields of millimeter (mm) waves by using quantum interferometric approach. The proposed quantum sensor consists of many surface-state electrons trapped individually on liquid helium by an electrode-network at the bottom of the liquid helium film. A dc-current in this chip is biased to generate a strong spin-orbit coupling of each of the trapped electrons. The mm wave signals are conducted to non-dissipatedly drive the orbital motions of the trapped electrons and result in the Stark shifts of the spin-orbit dressed states of the electrons. As a consequence, the electric fields of the conducted mm waves could be detected sensitively by using the Hahn echo interferometry with the long-lived spin states of the electrons trapped on liquid helium.

quant-ph

White Paper on Light Sterile Neutrino Searches and Related Phenomenology

This white paper provides a comprehensive review of our present understanding of experimental neutrino anomalies that remain unresolved, charting the progress achieved over the last decade at the experimental and phenomenological level, and sets the stage for future programmatic prospects in addressing those anomalies. It is purposed to serve as a guiding and motivational "encyclopedic" reference, with emphasis on needs and options for future exploration that may lead to the ultimate resolution of the anomalies. We see the main experimental, analysis, and theory-driven thrusts that will be essential to achieving this goal being: 1) Cover all anomaly sectors -- given the unresolved nature of all four canonical anomalies, it is imperative to support all pillars of a diverse experimental portfolio, source, reactor, decay-at-rest, decay-in-flight, and other methods/sources, to provide complementary probes of and increased precision for new physics explanations; 2) Pursue diverse signatures -- it is imperative that experiments make design and analysis choices that maximize sensitivity to as broad an array of these potential new physics signatures as possible; 3) Deepen theoretical engagement -- priority in the theory community should be placed on development of standard and beyond standard models relevant to all four short-baseline anomalies and the development of tools for efficient tests of these models with existing and future experimental datasets; 4) Openly share data -- Fluid communication between the experimental and theory communities will be required, which implies that both experimental data releases and theoretical calculations should be publicly available; and 5) Apply robust analysis techniques -- Appropriate statistical treatment is crucial to assess the compatibility of data sets within the context of any given model.

hep-ex

Measurement of Electron Antineutrino Oscillation Amplitude and Frequency via Neutron Capture on Hydrogen at Daya Bay

This Letter reports the first measurement of the oscillation amplitude and frequency of reactor antineutrinos at Daya Bay via neutron capture on hydrogen using 1958 days of data. With over 3.6 million signal candidates, an optimized candidate selection, improved treatment of backgrounds and efficiencies, refined energy calibration, and an energy response model for the capture-on-hydrogen sensitive region, the relative $\overlineν_{e}$ rates and energy spectra variation among the near and far detectors gives $\mathrm{sin}^22θ_{13} = 0.0759_{-0.0049}^{+0.0050}$ and $Δm^2_{32} = (2.72^{+0.14}_{-0.15})\times10^{-3}$ eV$^2$ assuming the normal neutrino mass ordering, and $Δm^2_{32} = (-2.83^{+0.15}_{-0.14})\times10^{-3}$ eV$^2$ for the inverted neutrino mass ordering. This estimate of $\sin^2 2θ_{13}$ is consistent with and essentially independent from the one obtained using the capture-on-gadolinium sample at Daya Bay. The combination of these two results yields $\mathrm{sin}^22θ_{13}= 0.0833\pm0.0022$, which represents an 8% relative improvement in precision regarding the Daya Bay full 3158-day capture-on-gadolinium result.

hep-ex

Search for a sub-eV sterile neutrino using Daya Bay's full dataset

This Letter presents results of a search for the mixing of a sub-eV sterile neutrino with three active neutrinos based on the full data sample of the Daya Bay Reactor Neutrino Experiment, collected during 3158 days of detector operation, which contains $5.55 \times 10^{6}$ reactor \anue candidates identified as inverse beta-decay interactions followed by neutron-capture on gadolinium. The analysis benefits from a doubling of the statistics of our previous result and from improvements of several important systematic uncertainties. No significant oscillation due to mixing of a sub-eV sterile neutrino with active neutrinos was found. Exclusion limits are set by both Feldman-Cousins and CLs methods. Light sterile neutrino mixing with $\sin^2 2θ_{14} \gtrsim 0.01$ can be excluded at 95\% confidence level in the region of $0.01$ eV$^2 \lesssim |Δm^{2}_{41}| \lesssim 0.1 $ eV$^2$. This result represents the world-leading constraints in the region of $2 \times 10^{-4}$ eV$^2 \lesssim |Δm^{2}_{41}| \lesssim 0.2 $ eV$^2$.

hep-ex

Neutron radius determination of 133Cs and its impact on the interpretation of CEvNS-CsI measurement

Proton-$^{133}$Cs elastic scattering at low momentum transfer is performed using an in-ring reaction technique at the Cooler Storage Ring at the Heavy Ion Research Facility in Lanzhou. Recoil protons from the elastic collisions between the internal H$_2$-gas target and the circulating $^{133}$Cs ions at 199.4 MeV/u are detected by a silicon-strip detector. The matter radius of $^{133}$Cs is deduced by describing the measured differential cross sections using the Glauber model. Employing the adopted proton distribution radius, a point-neutron radius of 4.86(21) fm for $^{133}$Cs is obtained. With the newly determined neutron radius, the weak mixing angle sin$^2 θ_W$ is independently extracted to be 0.227(28) by fitting the coherent elastic neutrino-nucleus scattering data. Our work limits the sin$^2 θ_W$ value in a range smaller than the ones proposed by the previous independent approaches, and would play an important role in searching new physics via the high precision CE$ν$NS-CsI cross section data in the near future.

nucl-ex

Charged-current non-standard neutrino interactions at Daya Bay

The full data set of the Daya Bay reactor neutrino experiment is used to probe the effect of the charged current non-standard interactions (CC-NSI) on neutrino oscillation experiments. Two different approaches are applied and constraints on the corresponding CC-NSI parameters are obtained with the neutrino flux taken from the Huber-Mueller model with a $5\%$ uncertainty. For the quantum mechanics-based approach (QM-NSI), the constraints on the CC-NSI parameters $ε_{eα}$ and $ε_{eα}^{s}$ are extracted with and without the assumption that the effects of the new physics are the same in the production and detection processes, respectively. The approach based on the weak effective field theory (WEFT-NSI) deals with four types of CC-NSI represented by the parameters $[\varepsilon_{X}]_{eα}$. For both approaches, the results for the CC-NSI parameters are shown for cases with various fixed values of the CC-NSI and the Dirac CP-violating phases, and when they are allowed to vary freely. We find that constraints on the QM-NSI parameters $ε_{eα}$ and $ε_{eα}^{s}$ from the Daya Bay experiment alone can reach the order $\mathcal{O}(0.01)$ for the former and $\mathcal{O}(0.1)$ for the latter, while for WEFT-NSI parameters $[\varepsilon_{X}]_{eα}$, we obtain $\mathcal{O}(0.1)$ for both cases.

hep-ph

First measurement of the yield of $^8$He isotopes produced in liquid scintillator by cosmic-ray muons at Daya Bay

Daya Bay presents the first measurement of cosmogenic $^8$He isotope production in liquid scintillator, using an innovative method for identifying cascade decays of $^8$He and its child isotope, $^8$Li. We also measure the production yield of $^9$Li isotopes using well-established methodology. The results, in units of 10$^{-8}μ^{-1}$g$^{-1}$cm$^{2}$, are 0.307$\pm$0.042, 0.341$\pm$0.040, and 0.546$\pm$0.076 for $^8$He, and 6.73$\pm$0.73, 6.75$\pm$0.70, and 13.74$\pm$0.82 for $^9$Li at average muon energies of 63.9~GeV, 64.7~GeV, and 143.0~GeV, respectively. The measured production rate of $^8$He isotopes is more than an order of magnitude lower than any other measurement of cosmogenic isotope production. It replaces the results of previous attempts to determine the ratio of $^8$He to $^9$Li production that yielded a wide range of limits from 0 to 30\%. The results provide future liquid-scintillator-based experiments with improved ability to predict cosmogenic backgrounds.

nucl-ex

Impact of the Dresden-II and COHERENT neutrino scattering data on neutrino electromagnetic properties and electroweak physics

Coherent elastic neutrino-nucleus scattering (CE$ν$NS) represents a powerful tool to investigate key electroweak physics parameters and neutrino properties since its first observation in 2017 by the COHERENT experiment exploiting the spallation neutron source at Oak Ridge National Laboratory. In light of the recent detection of such a process with antineutrinos produced by the Dresden-II reactor scattering off a germanium detector, we revisit the limits so far set on the neutrino magnetic moments, charge radii and millicharges as well as on the weak mixing angle. In order to do so, we also include the contribution of elastic neutrino-electron scattering, whose effect becomes non negligible in some beyond the Standard Model theories. By using different hypotheses for the germanium quenching factor and the reactor antineutrino flux, we provide a measurement of the weak mixing angle at the low-energy scale of the Dresden-II reactor experiment and, thanks to a combined analysis with the latest cesium iodide and argon data set released by the COHERENT Collaboration, we deliver updated limits for the neutrino electromagnetic properties. Interestingly, we are able to set a new best upper limit on the electron neutrino charge radius and significantly improve the other CE$ν$NS-related limits on the neutrino electric charge and magnetic moment.

hep-ph

Inspection of the detection cross section dependence of the Gallium Anomaly

We discuss in detail the dependence of the Gallium Anomaly on the detection cross section. We provide updated values of the size of the Gallium Anomaly and find that its significance is larger than about $5σ$ for all the detection cross section models. We discuss the dependence of the Gallium Anomaly on the assumed value of the half life of ${}^{71}\text{Ge}$, which determines the cross sections of the transitions from the ground state of ${}^{71}\text{Ga}$ to the ground state of ${}^{71}\text{Ge}$. We show that a value of the ${}^{71}\text{Ge}$ half life which is larger than the standard one can reduce or even solve the Gallium Anomaly. Considering the short-baseline neutrino oscillation interpretation of the Gallium Anomaly, we show that a value of the ${}^{71}\text{Ge}$ half life which is larger than the standard one can reduce the tension with the results of other experiments. Since the standard value of the ${}^{71}\text{Ge}$ half life was measured in 1985, we advocate the importance of new measurements with modern technique and apparatus for a better assessment of the Gallium Anomaly.

hep-ph

Precision measurement of reactor antineutrino oscillation at kilometer-scale baselines by Daya Bay

We present a new determination of the smallest neutrino mixing angle $θ_{13}$ and the mass-squared difference $Δ{\rm m}^{2}_{32}$ using a final sample of $5.55 \times 10^{6}$ inverse beta-decay (IBD) candidates with the final-state neutron captured on gadolinium. This sample was selected from the complete data set obtained by the Daya Bay reactor neutrino experiment in 3158 days of operation. Compared to the previous Daya Bay results, selection of IBD candidates has been optimized, energy calibration refined, and treatment of backgrounds further improved. The resulting oscillation parameters are ${\rm sin}^{2}2θ_{13} = 0.0851 \pm 0.0024$, $Δ{\rm m}^{2}_{32} = (2.466 \pm 0.060) \times 10^{-3}{\rm eV}^{2}$ for the normal mass ordering or $Δ{\rm m}^{2}_{32} = -(2.571 \pm 0.060) \times 10^{-3} {\rm eV}^{2}$ for the inverted mass ordering.

hep-ex

Gallium Anomaly: Critical View from the Global Picture of $ν_{e}$ and $\barν_{e}$ Disappearance

The significance of the Gallium Anomaly, from the BEST, GALLEX, and SAGE radioactive source experiments, is quantified using different theoretical calculations of the neutrino detection cross section, and its explanation due to neutrino oscillations is compared with the bounds from the analyses of reactor rate and spectral ratio data, $β$-decay data, and solar neutrino data. In the 3+1 active-sterile neutrino mixing scheme, the Gallium Anomaly is in strong tension with the individual and combined bounds of these data sets. In the combined scenario with all available data, the parameter goodness of fit is below 0.042%, corresponding to a severe tension of 4-5$σ$, or stronger. Therefore, we conclude that one should pursue other possible solutions beyond short-baseline oscillations for the Gallium Anomaly. We also present a new global fit of $ν_e$ and $\barν_e$ disappearance data, showing that there is a 2.6-3.3$σ$ preference in favor of short-baseline oscillations, which is driven by an updated analysis of reactor spectral ratio data.

hep-ph

First measurement of high-energy reactor antineutrinos at Daya Bay

This Letter reports the first measurement of high-energy reactor antineutrinos at Daya Bay, with nearly 9000 inverse beta decay candidates in the prompt energy region of 8-12~MeV observed over 1958 days of data collection. A multivariate analysis is used to separate 2500 signal events from background statistically. The hypothesis of no reactor antineutrinos with neutrino energy above 10~MeV is rejected with a significance of 6.2 standard deviations. A 29\% antineutrino flux deficit in the prompt energy region of 8-11~MeV is observed compared to a recent model prediction. We provide the unfolded antineutrino spectrum above 7 MeV as a data-based reference for other experiments. This result provides the first direct observation of the production of antineutrinos from several high-$Q_β$ isotopes in commercial reactors.

hep-ex

Probing light mediators and $(g-2)_μ$ through detection of coherent elastic neutrino nucleus scattering at COHERENT

We present the constraints on the parameters of several light boson mediator models obtained from the analysis of the current data of the COHERENT CE$ν$NS experiment. We consider a variety of vector boson mediator models: the so-called universal, the $B-L$ and other anomaly-free $U(1)'$ gauge models with direct couplings of the new vector boson with neutrinos and quarks, and the anomaly-free $L_e-L_μ$, $L_e-L_τ$, and $L_μ-L_τ$ gauge models where the coupling of the new vector boson with the quarks is generated by kinetic mixing with the photon at the one-loop level. We consider also a model with a new light scalar boson mediator that is assumed, for simplicity, to have universal coupling with quarks and leptons. Since the COHERENT CE$ν$NS data are well-fitted with the cross section predicted by the Standard Model, the analysis of the data yields constraints for the mass and coupling of the new boson mediator that depend on the charges of quarks and neutrinos in each model under consideration. We compare these constraints with the limits obtained in other experiments and with the values that can explain the muon $g-2$ anomaly in the models where the muon couples to the new boson mediator.

hep-ph