Weak Measurements Research Articles

Validity and Reliability Evidence and Norms for the Spanish Version of the Sexual Inhibition/Sexual Excitation Scales-Short Form.

The Sexual Inhibition/Sexual Excitation Scales-Short Form (SIS/SES-SF) is a brief instrument for assessing the propensity for sexual excitement and inhibition in men and women. The aim of the present study was to provide evidence for the validity and reliability of the Spanish version of the SIS/SES-SF scores by examining invariance, reliability (information function and internal consistency), the relationship between the scores and sexual functioning, and presenting its standard scores. A total of 2,223 Spanish heterosexuals (43.41% men and 56.59% women) aged 18 to 83 years (M = 39.94, SD = 11.95), distributed across age groups (18-34, 35-49, ≥ 50 years old) participated. The three-factor structure of the Spanish version of SIS/SES-SF showed weak measurement invariance by sex and strict measurement invariance by age. The scores explained the dimensions of sexual functioning, especially sexual arousal and erection/lubrication. In addition, men and women without difficulties in sexual functioning demonstrated more propensity for sexual excitation and less sexual inhibition. The standard scores are presented by sex and age group. The study provides evidence of the validity and reliability of the SIS/SES-SF measures, confirming its usefulness for assessing propensity to sexual excitation and inhibition.

Parameter estimation from quantum-jump data using neural networks

We present an inference method utilizing artificial neural networks for parameter estimation of a quantum probe monitored through a single continuous measurement. Unlike existing approaches focusing on the diffusive signals generated by continuous weak measurements, our method harnesses quantum correlations in discrete photon-counting data characterized by quantum jumps. We benchmark the precision of this method against Bayesian inference, which is optimal in the sense of information retrieval. By using numerical experiments on a two-level quantum system, we demonstrate that our approach can achieve a similar optimal performance as Bayesian inference, while drastically reducing computational costs. Additionally, the method exhibits robustness against the presence of imperfections in both measurement and training data. This approach offers a promising and computationally efficient tool for quantum parameter estimation with photon-counting data, relevant for applications such as quantum sensing or quantum imaging, as well as robust calibration tasks in laboratory-based settings.

Mid-infrared single-photon upconversion spectroscopy enabled by nonlocal wavelength-to-time mapping.

Ultrasensitive spectroscopy is an essential component in mid-infrared (MIR) technology. However, the drawbacks of MIR detectors pose challenges to robust MIR spectroscopy at the single-photon level. We propose an MIR single-photon frequency upconversion spectroscopy nonlocally mapping the MIR information to the time domain. Broadband MIR photons from spontaneous parametric downconversion are frequency-upconverted to the near-infrared band with quantum correlation preservation. Via the group delay of fiber, the MIR spectral information within a 1.18-micrometer bandwidth of 2.76 to 3.94 micrometers is then successfully projected to arrival times of correlated photon pairs. Under the conditions of 6.4 × 106 photons per second illumination, the transmission spectra of polymers with single-photon sensitivity are demonstrated using single-pixel detectors. The developed approach circumvents scanning and frequency selection instability, which stands out for its inherent compatibility for evolving environments and scalability for various wavelengths. Because of its high sensitivity and robustness, characterization of biochemical samples and weak measurement of quantum systems are possible to foresee.

Enhancing hierarchical remote preparation of an arbitrary n-qudit equatorial state by weak measurement and measurement reversal

Based on the demand for safer and more efficient quantum network communication, we propose two deterministic protocols to achieve the remote preparation of an arbitrary n-qudit equatorial states among multiple agents by selecting appropriate entanglement resources. The level of the agents varies depending on their authorities to restore the secret state. The superior agent requires the cooperation of the residual superior agents and any one of the subordinate agents, while the subordinate agent needs the help of all the other agents. To be emphasized, the recovery operations are deduced by general formulas that distinctly elucidate their relevance with the measurement outcomes. Additionally, we discuss the impact of amplitude damping noise and utilize weak measurement and measurement reversal to suppress noise.

Tunable quantized spin Hall effect of light in graphene

The spin Hall effect of light is an appealing toolset for metrology that holds incredible potential for precision measurements due to its high sensitivity to the refractive index and nanostructure physical parameters. Here, we theoretically examine the quantized spin Hall effect of light on the surface of a monolayer graphene–substrate system subjected to an external perpendicular magnetic field. We discuss the impact of Landau levels induced by the external magnetic field B and the photon energy on magneto-optical conductivities and Fresnel reflection coefficients. We find that the spin-dependent splittings in graphene exhibit quantized characteristics due to the Landau levels quantization of the magneto-optical conductivities and Fresnel’s reflection coefficients near the Brewster angle. Moreover, the spin-dependent shifts are quantized and show oscillatory behavior with changes in the magnetic field and the photon energy. Our results manifest that the quantized photonic spin-dependent separations are sensitive to variations in the incidence angle, magnetic field, and incident photonic energies. The quantized spin-dependent splitting opens a promising route to find the quantized Hall conductivity and discrete Landau levels in the monolayer graphene by a direct optical weak measurement.

Nonlocal approximation of nonlinear diffusion equations

We show that degenerate nonlinear diffusion equations can be asymptotically obtained as a limit from a class of nonlocal partial differential equations. The nonlocal equations are obtained as gradient flows of interaction-like energies approximating the internal energy. We construct weak solutions as the limit of a (sub)sequence of weak measure solutions by using the Jordan-Kinderlehrer-Otto scheme from the context of 2-Wasserstein gradient flows. Our strategy allows to cover the porous medium equation, for the general slow diffusion case, extending previous results in the literature. As a byproduct of our analysis, we provide a qualitative particle approximation.

Weak coupling strength measurement between two whispering-gallery-mode microresonators near an exceptional point

Sensing is one of the important applications of the whispering-gallery-mode (WGM) microresonator. Here we consider a model consisting of two WGM microresonators and one fiber waveguide. We show that the system can be near an exceptional point when the two tapers in the fiber waveguide are coupled to the two microresonators in a way that can lead to an unidirectional coupling. We propose a method to measure the weak coupling strength between the two microresonators. Compared to the conventional method, our method operates near an exceptional point and has the ability to measure smaller coupling strength.

Photonic spin Hall effect under the action of a full-angle three-dimensional magnetic field in space

In this paper, we have measured the magneto-optical spin Hall effect influenced by an arbitrary oriented magnetic field using CeDyAl thin films on Gd3Ga5O12 (GGG) substrates as reflective materials. Plots of the variation of the magneto-optic spin Hall effect (MOPSHE) with magnetic field strength, the hysteresis line, in three different unit-direction magnetic fields are simulated and experimentally measured. The comparison of the simulation results with the experiments allows the method of weak measurement to determine the MOPSHE under the influence of the magnetic field to be validated. MOPSHE under a three-dimensional magnetic field is measured and the measurement error is within 4 μm.

The history and mass content of cluster galaxies in the EAGLE simulation

We explore the mass content of galaxies residing in galaxy clusters at $z=0$ in the cosmological hydrodynamical simulation. We also explore the galaxies' mass build-up through cosmic time. We used a galaxy catalogue generated with the algorithm, which identifies subhaloes consistently over time by tracking their dynamical evolution throughout the simulation. The satellite subhalo-to-stellar mass relation (SHSMR) is well described by a double power law, becoming increasingly steeper with stellar mass. At stellar masses $9< satellites have 20-25 the subhalo mass of central galaxies at fixed stellar mass. At high stellar masses, $ the satellite SHSMR is consistent with that of centrals. The satellite SHSMR decreases steeply for satellites closer to the cluster centre, even in projection, broadly consistent with recent weak lensing measurements. The scatter in the satellite SHSMR is larger than that of central galaxies at all cluster masses and cluster-centric distances $R<R_ 200m $. The SHSMR scatter decreases with stellar mass by about 12 over an order of magnitude, but this dependence can be explained by the mixing of infall times when binning by stellar mass. By splitting satellites into direct and indirect infallers (those that fell into their current host as a central galaxy or as the satellite of an infalling group, respectively) we clearly show the impact of pre-processing separately on satellite galaxies' dark and stellar mass. There is significant dark matter pre-processing; the most recent infallers into massive clusters ($ had already lost up to 50 of their dark matter by the time of infall, particularly if they fell in indirectly as satellites of another host. On the contrary, on average, satellite galaxies are still gaining stellar mass at the time of infall and they do so for another 2 Gyr afterwards, although we see evidence of a slowing growth for indirect infallers. How much and for how long they continue to gain stellar mass depends primarily on the gas mass fraction available at infall. Overall, pre- and post-processing have similar impacts on the satellite SHSMR. Finally, we provide a simple prescription to infer the mean mass loss experienced by satellites as a function of cluster-centric distance based on a comparison to central galaxies, convenient for observational weak lensing measurements.

Design of weak current measurement system and research on temperature impact

Design of weak current measurement system and research on temperature impact

Multidimensional Spectroscopy of Nuclear Spin Clusters in Diamond.

Optically active spin defects in solids offer promising platforms to investigate nuclear spin clusters with high sensitivity and atomic-site resolution. To leverage near-surface defects for molecular structure analysis in chemical and biological contexts using nuclear magnetic resonance (NMR), further advances in spectroscopic characterization of nuclear environments are essential. Here, we report Fourier spectroscopy techniques to improve localization and mapping of the test bed ^{13}C nuclear spin environment of individual, shallow nitrogen-vacancy centers at room temperature. We use multidimensional spectroscopy, well-known from classical NMR, in combination with weak measurements of single-nuclear-spin precession. We demonstrate two examples of multidimensional NMR: (i)improved nuclear spin localization by separate encoding of the two hyperfine components along spectral dimensions and (ii)spectral editing of nuclear-spin pairs, including measurement of internuclear coupling constants. Our work adds important tools for the spectroscopic analysis of molecular structures by single-spin probes.

Stokes vector characterization by strongly measuring weak values.

We report the implementation of a non-standard procedure to perform Stokes polarimetry, which was recently proposed by considering weak value measurements. Our procedure is not restricted to weak measurements but applies for both weak and strong couplings between the observable being measured; the polarization (spin) vector; and the measuring device, the "pointer." In optics, the polarization-pointer coupling is usually implemented with a birefringent crystal. This applies in the weak coupling regime. We overcame this limitation by using an alternative setup in which one can go from weak to strong couplings by tuning a moveable mirror. We carried out our proof-of-concept experiments with a laser beam, the image of which was recorded and processed on a charge-coupled device. Our results illustrate that some concepts, originally introduced in a quantum context, in fact refer to properties that are common to both quantum and classical phenomena.

Copper ion concentration detection based on quantum weak measurement of circular dichroism

In this paper, a high precision detection method of copper ion (Cu2+) concentration based on weak measurement is proposed. The ternary complex formed by Cu2+ with L-tryptophan and phenanthroline reagents has circular dichroism (CD) signal at 605 nm in visible light. The CD signal can be obtained using the intensity contrast as a pointer in the imaginary weak-value amplification scheme. The measured sensitivity and resolution are 0.3417 mradl/mg and 0.058 mg/l, respectively, which is improved by an order of magnitude compared to the traditional CD measurement method. It is also more accurate and less costly than commonly used Cu2+ detection methods. The Cu2+ concentration detection based on the weak measurement of CD signal detection proposed in this paper not only brings technological breakthroughs in the field of heavy metal ion detection, but also is of great significance in promoting the cross-development of chemistry, biomedicine, and life sciences.

High-precision weak measurement sensing with adaptability in sensitivity

In the field of sensing technology, there is a trade-off between sensitivity and dynamic range. This paper proposes a high-precision weak measurement sensing method with flexible sensitivity adjustment to achieve matching between sensitivity and dynamic range. We demonstrate that precise control over sensitivity can be achieved by adjusting the bandwidth and coupling strength of the probe in frequency domain. In the experiment, the sensitivity ranges from 104 to 105RIU−1, and the precision ranges from 10−7 to 10−8 RIU. Additionally, the decomposition of hydrogen peroxide was precisely measured. Our measurement scheme can facilitate broader application of weak measurement technology in precision sensing.

High-sensitivity determination of ethanol concentration based on weak measurement system with Faraday effect

A high-sensitivity detection method is proposed for ethanol concentration based on weak measurement system with Faraday effect, and the improvement law of the sensitivity is studied. Different from chiral solution determination, the post-selection angle of the system is modified by the Faraday rotation angle of ethanol solution. The amplified photonic spin Hall effect acts as a probe for detecting the ethanol concentration in the system, and the sensitivity of ethanol concentration increases linearly with the increasing magnetic field intensity. Then we use the method to determine the ethanol concentration of commercial liquor, whose determination values are consistent with the label values and Raman spectroscopy results. Compared to other methods such as Raman spectrometry, the method has the advantages of real time, non-invasiveness, low cost and high sensitivity. Finally, the sensitivity of ethanol concentration can be further improved by designing of a suitable BK7-medium structure, and the sensitivity of 9.72 /vol% is achievable for the range 0 vol% ∼100 vol% of ethanol solutions.

Entanglement quantification via weak measurements assisted by deep learning

Entanglement has been recognized as being crucial when implementing various quantum information tasks. Nevertheless, quantifying entanglement for an unknown quantum state requires nonphysical operations or post-processing measurement data. For example, evaluation methods via quantum state tomography require vast amounts of measurement data and likely estimation. Although a direct entanglement determination has been reported for the unknown pure state, it is still tricky for the mixed state. In this work, assisted by weak measurement and deep learning technology, we directly detect the entanglement (namely, the concurrence) of a class of two-photon polarization-entangled mixed states both theoretically and experimentally according to the local photon spatial distributions after weak measurement. In this way, the number of projective bases is much smaller than that required in quantum state tomography.

Super amplification enabled by orbital angular momentum in weak measurement.

Weak measurement, which can amplify a weak signal, has shown great significance in precision measurements. The amplification is usually realized through the weak value and the propagation factor. We show that the orbital angular momentum (OAM) can provide another dimension for amplification that is linearly proportional to the OAM number. We employ OAM to measure the spin Hall effect of light and demonstrate that the OAM-enabled amplification is compatible with the weak value amplification and the propagation amplification. This work is probable to promote the application of OAM in precision measurements.

Weak solution and invariant probability measure for McKean-Vlasov SDEs with integrable drifts

In this paper, by utilizing Wang's Harnack inequality with power and the Banach fixed point theorem, the weak well-posedness for McKean-Vlasov SDEs with integrable drift is investigated. In addition, by Banach's fixed theorem, the existence and uniqueness of invariant probability measure for symmetric McKean-Vlasov SDEs and stochastic Hamiltonian system with integrable drifts are obtained.

Experimental verification of quantum contextuality using a weak measurement in a single trapped ion

Experimental verification of quantum contextuality using a weak measurement in a single trapped ion

Design and evaluation of a calibration system for portable motor vehicle emission particle number detectors

The supervision of the number concentration of particles emitted from motor vehicles is becoming increasingly strict. The regular calibration of portable particle number (PN) detectors is a prerequisite to ensure the effective supervision of PN. At present, the calibration of PN detectors is mostly completed in the laboratory. However, due to the complexity and poor portability of the laboratory calibration system, it is difficult to use this system for the on-site calibration of PN detectors. To this end, a portable motor vehicle emission PN detector calibration system based on the principles of negative pressure siphon atomization, differential electrical mobility classifier, and fA-level weak current measurement was developed, which could quickly and accurately calibrate the PN detector on-site. The system consists of three parts: an atomizer generator, a plate differential mobility analyzer (PDMA), and an aerosol electrometer. The atomizer generator produces NaCl particles with a median particle size of 70 nm and fluctuation of <10%. The particle size classification deviation of the PDMA is <3.7% and the counting error of the aerosol electrometer is <10%. The On-board Emissions Measurement System was calibrated as a PN detector on a self-developed portable calibration system as well as on a laboratory calibration system. The comparison results showed that the measurement results of the portable calibration system were closer to the instrument factory report certificate results, and the maximum error did not exceed 6.72%.