arXiv subjects

Yiqiu Ma

Publications and source records attributed to Yiqiu Ma.

At least 37 records · Page 2Linked to original sources

arXiv2023

A construction method of the quasi-monolithic compact interferometer based on UV-adhesives bonding

Quasi-monolithic interferometers play a crucial role in high-precision measurement experiments, including gravitational wave detection, inertial sensing, vibrometry, and seismology. Achieving high stability and accuracy in such interferometers requires a method for bonding optical components to a baseplate. While optical contact bonding and silicate bonding are common methods, UV adhesives offer advantages such as controlled curing and low geometrical requirements for optical components and baseplates. This paper presents a detailed construction method for a quasi-monolithic compact interferometer based on UV-adhesive bonding. We built two types of interferometers using this method: a $100\,{\rm mm} \times 100\,{\rm mm}\times 20\,{\rm mm}$ Mach-Zender homodyne interferometer with unequal arm lengths of about $100\,{\rm mm}$ for laser frequency noise monitoring, and a heterodyne interferometer as a displacement sensing head sizing $20\,{\rm mm} \times 30\,{\rm mm}\times 20\,{\rm mm}$. Our Mach-Zender interferometer achieved a phase noise level of $2\,μ{\rm rad}\sqrt{\rm Hz}$ at $1\,{\rm Hz}$ and a equivalent laser frequency noise monitoring sensitivity of about $1\,{\rm kHz}/\sqrt{\rm Hz}$ at $1\,{\rm Hz}$. The compact heterodyne interferometer sensing head showed a sensitivity level of $1\,{\rm pm}/\sqrt{\rm Hz}$ in translation and $0.2\,{\rm nrad}/\sqrt{\rm Hz}$ in two tilts above $0.4\,{\rm Hz}$. Our tests demonstrate that quasi-monolithic compact interferometers based on UV-adhesive bonding can achieve high sensitivity levels at the pico-meter and nano-radian scales.

physics.ins-det↗

arXiv2023

On the noise effect of test mass surface roughness in spaceborne gravitational wave detectors

Spaceborne gravitational wave detection mission has a demanding requirement for the precision of displacement sensing, which is conducted by the interaction between the laser field and test mass. However, due to the roughness of the reflecting surface of the test mass, the displacement measurement along the sensitive axis suffers a coupling error caused by the residue motion of other degrees of freedom. In this article, we model the coupling of the test mass residue random motion to the displacement sensing along the sensitive axis and derived an analytical formula of the required precision of the surface error for the spaceborne gravitational wave detectors. Our result shows that this coupling error will not contaminate the picometer displacement sensing for the test masses in the LISA pathfinder.

physics.ins-det↗

arXiv2023

Accretion-modified stellar-mass black hole distribution and milli-Hz gravitational wave backgrounds from galaxy centre

Gas accretion of embedded stellar-mass black holes\,(sBHs) or stars in the accretion disk of active galactic nuclei\,(AGNs) will modify the mass distribution of these sBHs and stars, which will also affect the migration of the sBHs/stars. With the introduction of the mass accretion effect, we simulate the evolution of the sBH/star distribution function in a consistent way by extending the Fokker-Planck equation of sBH/star distributions to the mass-varying scenario, and explore the mass distribution of sBHs in the nuclear region of the galaxy centre. We find that the sBHs can grow up to several tens solar mass and form heavier sBH binaries, which will be helpful for us to understand the black-hole mass distribution as observed by the current and future ground-based gravitational wave detectors\,(e.g., LIGO/VIRGO, ET and Cosmic Explorer). We further estimate the event rate of extreme mass-ratio inspirals\,(EMRI) for sBH surrounding the massive black hole and calculate the stochastic gravitational wave\,(GW) background of the EMRIs. We find that the background can be detected in future space-borne GW detectors after considering the sBHs embedded in the AGN disk, while the mass accretion has a slight effect on the GW background.

astro-ph.HE↗

arXiv2022

Probing phase transition in neutron stars via the crust-core interfacial mode

Gravitational waves emitted from the binary neutron star (BNS) systems can carry information about the dense matter phase in these compact stars. The crust-core interfacial mode is an oscillation mode in a neutron star and it depends mostly on the equation of the state of the matter in the crust-core transition region. This mode can be resonantly excited by the tidal field of an inspiraling-in BNS system, thereby affecting the emitted gravitational waves, and hence could be used to probe the equation of state in the crust-core transition region. In this work, we investigate in detail how the first-order phase transition inside the neutron star affects the properties of the crust-core interfacial mode, using a Newtonian fluid perturbation theory on a general relativistic background solution of the stellar structure. Two possible types of phase transitions are considered: (1) the phase transitions happen in the fluid core but near the crust-core interface, which results in density discontinuities; and (2) the strong interaction phase transitions in the dense core (as in the conventional hybrid star case). These phase transitions' impacts on interfacial mode properties are discussed. In particular, the former phase transition has a minor effect on the M-R relation and the adiabatic tidal deformability, but can significantly affect the interfacial mode frequency and thereby could be probed using gravitational waves. For the BNS systems, we discuss the possible observational signatures of these phase transitions in the gravitational waveforms and their detectability. Our work enriches the exploration of the physical properties of the crust-core interfacial mode and provides a promising method for probing the phase transition using the seismology of a compact star.

astro-ph.HE↗

arXiv2022

Quantum scrambling in a toy model of photodetectors

Quantum measurement is a process that involves the interaction between a quantum system and a macroscopic measurement apparatus containing many degrees of freedom. The photodetector is such an apparatus with many electrons interacting with the incoming quantum photon. Therefore the incoming photon will spread and get scrambled in the photodetector, that is, the operator of the initial incoming local photons will grow and becomes highly non-local through the interaction process. Investigating this scrambling process in detail is useful for understanding the interaction between the quantum system and the measurement apparatus. In this paper, we study the quantum scrambling process in an effective toy model of photodetectors in three different physical scenarios, by numerically simulating the evolution of the out-of-time correlators (OTOC). In particular, the integrability of the effective model is explored through level spacing statistics, and the effect of the spatially/temporarily distributed disorders on the system evolution is carefully investigated using the OTOC. Looking into these detailed dynamical processes paves the way to the quantum simulation and manipulation of photondetector, which would provide insights into understanding the wave-function collapse processes.

quant-ph↗

arXiv2022

Semi-classical gravity phenomenology under the causal-conditional quantum measurement prescription

The semi-classical gravity sourced by the quantum expectation value of the matter's energy-momentum tensor will change the evolution of the quantum state of matter. This effect can be described by the Schroedinger-Newton (SN) equation, where the semi-classical gravity contributes a gravitational potential term depending on the matter quantum state. This state-dependent potential introduces the complexity of the quantum state evolution and measurement in SN theory, which is different for different quantum measurement prescriptions. Previous theoretical investigations on the SN-theory phenomenology in the optomechanical experimental platform were carried out under the so-called post/pre-selection prescription. This work will focus on the phenomenology of SN theory under the causal-conditional prescription, which fits the standard intuition on the continuous quantum measurement process. Under the causal-conditional prescription, the quantum state of the test mass mirrors is conditionally and continuously prepared by the projection of the outgoing light field in the optomechanical system. Therefore a gravitational potential depends on the quantum trajectory is created and further affects the system evolution. In this work, we will systematically study various experimentally measurable signatures of SN theory under the causal-conditional prescription in an optomechanical system, for both the self-gravity and the mutual gravity scenarios. Comparisons between the SN phenomenology under three different prescriptions will also be carefully made. Moreover, we find that quantum measurement can induce a classical correlation between two different optical fields via classical gravity, which is difficult to be distinguished from the quantum correlation of light fields mediated by quantum gravity.

quant-ph↗

arXiv2022

Boosting the sensitivity of high frequency gravitational wave detectors by PT-symmetry

The kilo-Hertz gravitational waves radiated by the neutron star merger remnants carry rich information about the physics of high-density nuclear matter states, and many important astrophysical phenomena such as gamma-ray bursts and black hole formation. Current laser interferometer gravitational wave detectors, such as LIGO, VIRGO, and KAGRA have limited signal response at the kilo-Hertz band, thereby unable to capture these important physical phenomena. This work proposes an alternative protocol for boosting the sensitivity of the gravitational wave detectors at high frequency by implementing an optomechanical quantum amplifier. With the auxiliary quantum amplifier, this design has the feature of Parity-Time (PT) symmetry so that the detection band will be significantly broadened within the kilo-Hertz range. In this work, we carefully analyze the quantum-noise-limited sensitivity and the dynamical stability of this design. Based on our protocol, our result shows that the quantum-noise-limited sensitivity will be improved by one order of magnitude around 3kHz, which indicates the potential of our design for a future search of neutron star merger signals.

gr-qc↗

arXiv2022

Scalable Simulation of Quantum Measurement Process with Quantum Computers

Recent development in quantum information sciences and technologies, especially building programmable quantum computers, provide us new opportunities to study fundamental aspects of quantum mechanics. We propose qubit models to emulate the quantum measurement process, in which the quantum information of a qubit is mapped to a collection of qubits acting as the measurement device. One model is motivated by single-photon detection and the other by spin measurement. Both models are scalable to generate Schrödinger cat-like state, and their corresponding quantum circuits are shown explicitly. Large-scale simulations could be realized in near-term quantum computers, while classical computers cannot perform the same task efficiently. Due to the scalability of the models, such simulations can help explore the quantum-to-classical boundary, if exists, in the quantum measurement problem. Besides, our protocol to generate cat states may have important applications in quantum computing and metrology.

quant-ph↗

arXiv2022

A model for the possible connection between tidal disruption event and quasi-periodic eruption in GSN 069

Quasi-periodic eruptions (QPEs) are found in the center of five galaxies, where a tidal disruption event (TDE)-like event is also reported in GSN 069 that happened a couple of years before the QPEs. We explain the connection of these phenomena based on a model of a highly eccentric white-dwarf (WD)-$10^{4-6}M_{\odot}$ massive black hole (MBH) binary formed by the Hill mechanism. In this system, the tidal induced internal oscillation of WD can heat the WD envelope thereby induces the tidal nova and inflates the WD envelope, which can be captured by the MBH and form a TDE. The tidal stripping of the surviving WD in the eccentric orbit can produce the QPEs. We also apply this model to the other four QPE sources. Based on the estimated fallback rate, we find that the remaining time after the QPE-observed time for these QPEs is only around 1-2 years based on our simple model estimation, and then the WD will be fully disrupted. We also show that the accretion rate can be much higher than Eddington accretion rate in final stage of these QPE sources. The peak frequency of spectral energy distribution of disk stays in soft X-ray band ($\sim 0.1-1$ keV), which is consistent with observational results.

astro-ph.HE↗

arXiv2022

Prospects and Strategies for Detecting Nonlinear Gravitational Wave Burst with Memory from Potential Merger Event SDSSJ1430$+$2303 by Pulsar Timing Arrays

The recently observed chirping signature in the light curves of Seyfert 1 galaxy SDSSJ1430$+$2303 could be explained by a late-inspiralling supermassive binary black hole (SMBBH) system in the galactic center, which will merge in the near future (or could have merged already). For the merging SMBBH scenario, SDSSJ1430$+$2303 can be a source of nonlinear gravitational wave (GW) burst with memory (BWM), which may provide a promising target for future pulsar timing array (PTA) observations. In this work, we investigate the prospects for detecting the BWM signal from SDSSJ1430$+$2303 by the International PTA (IPTA) and FAST-PTA in the next $5$ years. We firstly propose strategies on searching for this target signal, including the selection of millisecond pulsars (MSPs) and the distribution of observation time. Then we simulate PTA observations based on the proposed strategies and obtain the probability density functions of the network signal-to-noise ratio and parameter-estimation errors of the BWM signal, considering the uncertainties of parameters of the SMBBH and both white and red noises of the selected MSPs. Our result shows that although IPTA can marginally detect the BWM in $5$ years, FAST-PTA can detect it with significantly higher confidence. Moreover, the archived IPTA data is important in estimating the merger time of the SMBBH, when combined with the FAST-PTA data. This work can serve as a guidance for future PTA observations and multi-messenger studies on SDSSJ1430$+$2303 and similar systems.

astro-ph.HE↗

arXiv2022

Axion Haloscope Array With $\mathcal{PT}$ Symmetry

We generalize the recently proposed $\mathcal{P T}$-symmetric axion haloscope to a larger array with more $\mathcal{P T}$-symmetric structures. By broadening the response bandwidth of the signal without increasing the readout noise, the optimized scan rate of the axion haloscope is significantly enhanced, as well as is the signal power. Furthermore, we show that the robustness of the detector towards the variations of the array coupling is the strongest when a binary tree structure is introduced which contains a largely enhanced $\mathcal{P T}$ symmetry. The multiple allowed probing sensors can further increase the scan rate by a factor of the sensors' number due to the correlation of the signals. This type of array can strongly boost the search for an axion compared to single-mode resonant detection. The enhancement to the scan rate becomes the most manifest when applied to the proposed detection using a superconducting radio-frequency cavity with an ac magnetic field where most of the parameter space of the QCD axion above kHz can be probed.

hep-ph↗

arXiv2021

A Hybrid Rydberg Quantum Gate for Quantum Network

The high fidelity storage, distribution and processing of quantum information prefers qubits with different physical properties. Thus, hybrid quantum gates interfacing different types of qubits are essential for the realization of complex quantum network structures. A Rydberg-atom based physical quantum CZ gate is proposed to hybridly process the polarisation-encoded single-photon optical qubit and the "Schroedinger cat" microwave qubit. The degradation of the fidelity under the influence of various noise channels, such as microwave cavity loss, sponetanous emission of atom states, and non-adiabaticity effect, etc, has been analyised through detailed theoretical analysis by deriving input-output relation of qubit fields. The feasibility and the challenges of the protocol within current technology are also discussed by analysing the possible experimental parameter settings.

quant-ph↗

arXiv2021

Enhancing interferometer sensitivity without sacrificing bandwidth and stability: beyond single-mode and resolved-sideband approximation

Quantum noise limits the sensitivity of precision measurement devices, such as laser interferometer gravitational-wave observatories and axion detectors. In the shot-noise-limited regime, these resonant detectors are subject to a trade-off between the peak sensitivity and bandwidth. One approach to circumvent this limitation in gravitational-wave detectors is to embed an anomalous-dispersion optomechanical filter to broaden the bandwidth. The original filter cavity design, however, makes the entire system unstable. Recently, we proposed the coherent feedback between the arm cavity and the optomechanical filter to eliminate the instability via PT-symmetry. The original analysis based upon the Hamiltonian formalism adopted the single-mode and resolved-sideband approximations. In this paper, we go beyond these approximations and consider realistic parameters. We show that the main conclusion concerning stability remains intact, with both Nyquist analysis and a detailed time-domain simulation.

quant-ph↗

arXiv2020

Broadband sensitivity improvement via coherent quantum feedback with PT symmetry

A conventional resonant detector is often subject to a trade-off between bandwidth and peak sensitivity that can be traced back to quantum Cramer-Rao Bound. Anomalous dispersion has been shown to improve it by signal amplification and is thus more robust against decoherence, while it leads to instabilities. We propose a stable quantum amplifier applicable to linear systems operating at the fundamental detection limits, enabled by two-mode non-degenerate parametric amplification. At threshold, one mode of the amplifier forms a PT-symmetric system of original detector mode. Sensitivity improvements are shown for laser-interferometric gravitational-wave detectors and microwave cavity axion detectors.

quant-ph↗

arXiv2020

Gravitational wave detectors with broadband high frequency sensitivity

The binary neutron star coalescence GW170817 was observed by gravitational wave detectors during the inspiral phase but sensitivity in the 1-5 kHz band was insufficient to observe the expected nuclear matter signature of the merger itself, and the process of black hole formation. This provides strong motivation for improving 1--5 kHz sensitivity which is currently limited by photon shot noise. Resonant enhancement by signal recycling normally improves the signal to noise ratio at the expense of bandwidth. The concept of optomechanical white light signal recycling (WLSR) has been proposed, but all schemes to date have been reliant on the development of suitable ultra-low mechanical loss components. Here for the first time we show demonstrated optomechanical resonator structures that meet the loss requirements for a WLSR interferometer with strain sensitivity below 10$^{-24}$ Hz$^{-1/2}$ at a few kHz. Experimental data for two resonators are combined with analytic models of 4km interferometers similar to LIGO, to demonstrate sensitivity enhancement across a much broader band of neutron star coalescence frequencies than dual-recycled Fabry-Perot Michelson detectors of the same length. One candidate resonator is a silicon nitride membrane acoustically isolated from the environment by a phononic crystal. The other is a single-crystal quartz lens that supports bulk acoustic longitudinal waves. Optical power requirements could prefer the membrane resonator, although the bulk acoustic wave resonator gives somewhat better thermal noise performance. Both could be implemented as add-on components to existing detectors.

physics.optics↗

arXiv2019

Application of optomechanical frequency conversion on gravitational wave detection

Optomechanical interaction can be a platform for converting quantum optical sates at different frequencies. In this work, we propose to combine the idea of optomechanical frequency conversion and the dual-use of laser interferometer, for the purpose of improving the broadband sensitivity of laser interferometer gravitational wave detectors by filtering the light field. We found that compare to the previous schemes of implementing the optomechanical devices in gravitational wave detectors, this frequency converter scheme will have less stringent requirement on the thermal noise dilution.

quant-ph↗

arXiv2019

Linear quantum measurement theory of matter-wave interferometry

The theory of linear quantum measurement has been developed for analysing the sensitivities of experimental devices that measure extremely weak signals, such as gravitational waves. It has successfully contributed to the theoretical understanding of laser interferometer gravitational-wave detectors (used by LIGO, VIRGO and KaGRA) and helped many important experimental upgrades. In this work, we establish a linear quantum measurement theory for another kind of measurement device--- matter wave interferometers, which has been widely discussed as an important platform for many high-precision experiments. This theory allows us to account for both atom and light fluctuations, and leads to a detailed analysis of back-action in matter-wave interferometry (action of light back onto the atoms) and its effect on dynamics and measurement noise. From this analysis, we obtain a Standard Quantum Limit (SQL) for matter-wave interferometry. A comparison between the LIGO detector and matter wave interferometer is also given from the perspective of quantum measurement.

quant-ph↗

arXiv2019

Broadband Quantum Noise Reduction in Future Long Baseline Gravitational-wave Detectors via EPR Entanglement

Broadband quantum noise reduction can be achieved in gravitational wave detectors by injecting frequency dependent squeezed light into the the dark port of the interferometer. This frequency dependent squeezing can be generated by combining squeezed light with external filter cavities. However, in future long baseline interferometers (LBIs), the filter cavity required to achieve the broadband squeezing has a low bandwidth -- necessitating a very long cavity to mitigate the issue from optical loss. It has been shown recently that by taking advantage of Einstein-Podolsky-Rosen (EPR) entanglement in the squeezed light source, the interferometer can simultaneously act as a detector and a filter cavity. This is an attractive broadband squeezing scheme for LBIs because the length requirement for the filter cavity is naturally satisfied by the length of the interferometer arms. In this paper we present a systematic way of finding the working points for this broadband squeezing scheme in LBIs. We also show that in LBIs, the EPR scheme achieves nearly perfect ellipse rotation as compared to 4km interferometers which have appreciable error around the intermediate frequency. Finally, we show that an approximation for the opto-mechanical coupling constant in the 4km case can break down for longer baselines. These results are applicable to future detectors such as the 10km Einstein Telescope and the 40km Cosmic Explorer.

quant-ph↗