Observation of room-temperature polar skyrmions.

Complex topological configurations are fertile ground for exploring emergent phenomena and exotic phases in condensed-matter physics. For example, the recent discovery of polarization vortices and their associated complex-phase coexistence and response under applied electric fields in superlattices of (PbTiO3)n/(SrTiO3)n suggests the presence of a complex, multi-dimensional system capable of interesting physical responses, such as chirality, negative capacitance and large piezo-electric responses1-3. Here, by varying epitaxial constraints, we discover room-temperature polar-skyrmion bubbles in a lead titanate layer confined by strontium titanate layers, which are imaged by atomic-resolution scanning transmission electron microscopy. Phase-field modelling and second-principles calculations reveal that the polar-skyrmion bubbles have a skyrmion number of +1, and resonant soft-X-ray diffraction experiments show circular dichroism, confirming chirality. Such nanometre-scale polar-skyrmion bubbles are the electric analogues of magnetic skyrmions, and could contribute to the advancement of ferroelectrics towards functionalities incorporating emergent chirality and electrically controllable negative capacitance.

Polarization self-compensation in a laser-driven interferometric fiber optic gyroscope with high long-term stability.

We present a laser-driven interferometric fiber optic gyroscope (IFOG) with polarization self-compensation to achieve high scale-factor stability, sensitivity, and long-term stability. Coherent light with 200kHz linewidth is employed to keep the scale factor stable. The optical scheme ensures polarization reciprocity as well as the optimal working point for good sensitivity. Furthermore, a hybrid machine learning loop (MLL) method, combining the advantages of PID fast response and artificial neural network (ANN) dynamic search, can control a liquid crystal rotator (LCR) to dynamically compensate for slow drift induced by polarization coupling. In open environment, when the sensitivity is 0.005 ∘/h, the bias instability (BI) is significantly optimized from 0.6723°/h at 60s (PID) to 0.3869°/h at 200s (MLL), which is close to the Sagnac interferometric limit (SIL). Such IFOG can meet the real-time and robust requirements for inertial navigation systems in long-term measurement.

Coherent feedback enhanced quantum-dense metrology in a lossy environment.

Quantum dense metrology (QDM) performs high-precision measurements by a two-mode entangled state created by an optical parametric amplifier (PA), where one mode is a meter beam and the other is a reference beam. In practical applications, the photon losses of meter beam are unavoidable, resulting in a degradation of the sensitivity. Here, we employ coherent feedback that feeds the reference beam back into the PA by a beam splitter to enhance the sensitivity in a lossy environment. The results show that the sensitivity is enhanced significantly by adjusting the splitting ratio of the beam splitter. This method may find its potential applications in QDM. Furthermore, such a strategy that two non-commuting observables are simultaneous measurements could provide a new way to individually control the noise-induced random drift in phase or amplitude of the light field, which would be significant for stabilizing the system and long-term precision measurement.

New radiofrequency ablation procedure for selective reduction in complicated monochorionic twin or triplet pregnancy using multistep, incremental expansion technique.

OBJECTIVE: Radiofrequency ablation (RFA) is the preferred approach for selective reduction in complex monochorionic (MC) multiple pregnancies owing to the ease of operation and minimal invasiveness. To optimize the RFA technique and reduce the risk of adverse pregnancy outcome resulting from the heat-sink effect of RFA therapy, we used an innovative RFA method, in which an electrode needle was expanded incrementally and stepwise. This study aimed to assess the efficacy and safety profile of this novel multistep incremental expansion RFA method for selective fetal reduction in MC twin and triplet pregnancies. METHODS: This was a single-center retrospective cohort study of all MC multiple pregnancies undergoing RFA between March 2016 and October 2022 at our center. The multistep RFA technique involved the use of an expandable needle, which was gradually expanded during the RFA procedure until cessation of umbilical cord blood flow was achieved. The needle used for the single-step RFA method was fully extended from the start of treatment. RESULTS: In total, 132 MC multiple pregnancies underwent selective reduction using RFA, including 50 cases undergoing multistep RFA and 82 cases undergoing single-step RFA. The overall survival rates were not significantly different between the multistep and single-step RFA groups (81.1% vs 72.3%; P = 0.234). Similarly, the rates of preterm prelabor rupture of the membranes within 2 weeks after RFA, procedure-related complications, spontaneous preterm delivery and pathological findings on cranial ultrasound, as well as gestational age at delivery and birth weight, did not differ between the two groups. However, there was a trend towards a prolonged procedure-to-delivery interval following multistep RFA compared with single-step RFA (median, 109 vs 99 days; P = 0.377). Moreover, the fetal loss rate within 2 weeks after RFA in the multistep RFA group was significantly lower than that in the single-step RFA group (10.0% vs 24.4%; P = 0.041). The median ablation time was shorter (5.3 vs 7.8 min; P < 0.001) and the median ablation energy was lower (10.2 vs 18.0 kJ; P < 0.001) in multistep compared with single-step RFA. There were no significant differences in neonatal outcomes following multistep vs single-step RFA. CONCLUSIONS: Overall survival rates were similar between the two RFA methods. However, the multistep RFA technique was associated with a lower risk of fetal loss within 2 weeks after RFA. The multistep RFA technique required significantly less ablation energy and a shorter ablation time compared with single-step RFA in selective fetal reduction of MC twin and triplet pregnancies. Additionally, there was a trend towards a prolonged procedure-to-delivery interval with the multistep RFA technique. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

[A successfully treated case of respiratory failure caused by eating Nassariidaes].

Food poisoning caused by Nassariidaes has occurred frequently in coastal areas of China, especially in summer and autumn. Nassariidaes poisoning can be manifested as lip and tongue paralysis, dizziness, headache, nausea and vomiting, arrhythmia and even respiratory failure. We admitted a case of respiratory failure caused by eating Nassariidaes. After timely respiratory support, hemoperfusion and other active treatment, the patient was recovered and was discharged. This paper summarized clinical characteristics and treatment of Nassariidaes poisoning, in order to provide reference for clinical diagnosis and treatment of similar cases.

SERF-like magnetometry in room-temperature environment.

We demonstrate an atomic magnetometry using amplitude-modulated pumping and hyperfine repumping techniques in a paraffin-coated cell. By exploiting the constructive interference between spins polarized by the pump beam and an additional repump beam, we observe a three-fold increase in the amplitude of magnetic resonance, along with a reduction in linewidth by approximately two times. The implementation of the repump beam effectively narrows the linewidth, demonstrating successful suppression of spin-exchange relaxation. This reduction in relaxation rate, combined with the enhanced signal, significantly improves the sensitivity of the magnetometer. Consequently, our technique offers a promising approach for achieving SERF-like magnetometry with sub-fT-level sensitivity in Earth-field range and room-temperature environment.

Protection of Noise Squeezing in a Quantum Interferometer with Optimal Resource Allocation.

Interferometers are crucial for precision measurements, including gravitational waves, laser ranging, radar, and imaging. The phase sensitivity, the core parameter, can be quantum-enhanced to break the standard quantum limit (SQL) using quantum states. However, quantum states are highly fragile and quickly degrade with losses. We design and demonstrate a quantum interferometer utilizing a beam splitter with a variable splitting ratio to protect the quantum resource against environmental impacts. The optimal phase sensitivity can reach the quantum Cramér-Rao bound of the system. This quantum interferometer can greatly reduce the quantum source requirements in quantum measurements. In theory, with a 66.6% loss rate, the sensitivity can break the SQL using only a 6.0 dB squeezed quantum resource with the current interferometer rather than a 24 dB squeezed quantum resource with a conventional squeezing-vacuum-injected Mach-Zehnder interferometer. In experiments, when using a 2.0 dB squeezed vacuum state, the sensitivity enhancement remains at ∼1.6 dB via optimizing the first splitting ratio when the loss rate changes from 0% to 90%, indicating that the quantum resource is excellently protected with the existence of losses in practical applications. This strategy could open a way to retain quantum advantages for quantum information processing and quantum precision measurement in lossy environments.

Interferometry-Integrated Noise-Immune Quantum Memory.

A quantum memory with the performances of low noise, high efficiency, and high bandwidth is of crucial importance for developing practical quantum information technologies. However, the excess noises generated during the highly efficient processing of quantum information inevitably destroy quantum state. Here, we present a quantum memory with built-in excess-noise eraser by integrating a photon-correlated quantum interferometry in quantum memory, where the memory efficiency can be enhanced and the excess noises can be suppressed to the vacuum level via destructive interference. This quantum memory is demonstrated in a rubidium vapor cell with a 10-ns-long photonics signal. We observe ∼80% noise suppression, the write-in efficiency enhancement from 87% to 96.2% without and with interferometry, and the corresponding memory efficiency excluding the noises from 70% to 77%. The fidelity is 93.7% at the single-photon level, significantly exceeding the no-cloning limit. Such interferometry-integrated quantum memory, the first expansion of quantum interference techniques to quantum information processing, simultaneously enables low noise, high bandwidth, high efficiency, and easy operation.

Local negative permittivity and topological phase transition in polar skyrmions.

Topological solitons such as magnetic skyrmions have drawn attention as stable quasi-particle-like objects. The recent discovery of polar vortices and skyrmions in ferroelectric oxide superlattices has opened up new vistas to explore topology, emergent phenomena and approaches for manipulating such features with electric fields. Using macroscopic dielectric measurements, coupled with direct scanning convergent beam electron diffraction imaging on the atomic scale, theoretical phase-field simulations and second-principles calculations, we demonstrate that polar skyrmions in (PbTiO3)n/(SrTiO3)n superlattices are distinguished by a sheath of negative permittivity at the periphery of each skyrmion. This enhances the effective dielectric permittivity compared with the individual SrTiO3 and PbTiO3 layers. Moreover, the response of these topologically protected structures to electric field and temperature shows a reversible phase transition from the skyrmion state to a trivial uniform ferroelectric state, accompanied by large tunability of the dielectric permittivity. Pulsed switching measurements show a time-dependent evolution and recovery of the skyrmion state (and macroscopic dielectric response). The interrelationship between topological and dielectric properties presents an opportunity to simultaneously manipulate both by a single, and easily controlled, stimulus, the applied electric field.

Observation of polar vortices in oxide superlattices.

The complex interplay of spin, charge, orbital and lattice degrees of freedom provides a plethora of exotic phases and physical phenomena. In recent years, complex spin topologies have emerged as a consequence of the electronic band structure and the interplay between spin and spin-orbit coupling in materials. Here we produce complex topologies of electrical polarization--namely, nanometre-scale vortex-antivortex (that is, clockwise-anticlockwise) arrays that are reminiscent of rotational spin topologies--by making use of the competition between charge, orbital and lattice degrees of freedom in superlattices of alternating lead titanate and strontium titanate layers. Atomic-scale mapping of the polar atomic displacements by scanning transmission electron microscopy reveals the presence of long-range ordered vortex-antivortex arrays that exhibit nearly continuous polarization rotation. Phase-field modelling confirms that the vortex array is the low-energy state for a range of superlattice periods. Within this range, the large gradient energy from the vortex structure is counterbalanced by the corresponding large reduction in overall electrostatic energy (which would otherwise arise from polar discontinuities at the lead titanate/strontium titanate interfaces) and the elastic energy associated with epitaxial constraints and domain formation. These observations have implications for the creation of new states of matter (such as dipolar skyrmions, hedgehog states) and associated phenomena in ferroic materials, such as electrically controllable chirality.

Super-sensitive rotation measurement with an orbital angular momentum atom-light hybrid interferometer.

Lights carrying orbital angular momentum (OAM) have potential applications in precise rotation measurement, especially in remote sensing. Interferometers, especially nonlinear quantum interferometers, have also been proven to greatly improve the measurement accuracy in quantum metrology. By combining these two techniques, we theoretically propose a new atom-light hybrid Sagnac interferometer with OAM lights to advance the precision of the rotation measurement. A rotation sensitivity below standard quantum limit is achieved due to the enhancement of the quantum correlation of the interferometer even with 96% photon losses. This makes our protocol robustness to the photon loss. Furthermore, combining the slow light effect brings us at least four orders of magnitude of sensitivity better than the earth rotation rate. This new type interferometer has potential applications in high precision rotation sensing.

Quantum enhanced electro-optic sensor for E-field measurement.

The measurement of intense E-field is a fundamental need in various research areas. An electro-optic (EO) sensor based on common path interferometer (CPI) is widely used due to its better temperature stability and controllability of optical bias. However, the small EO coefficient leads to poor sensitivity. In this paper, a quantum enhanced EO sensor is proposed by replacing the vacuum state in classical one with a squeezed-vacuum state. Theoretical analysis shows that the performance of the quantum enhanced EO sensor, including signal to noise ratio (SNR) and sensitivity, can always beat the classical one due to the noise suppression caused by the squeezed-vacuum state. Experimental results demonstrate that, there is still a 1.12dB quantum enhancement compared with the classical one when the degree of the squeezed-vacuum is 1.60dB. More importantly, except the increase of the EO coefficient or the optical power, the performance of the EO sensor can also be enhanced via quantum light source. Such a quantum enhanced EO sensor could be practically applied for the measurement of intense E-field.

[Determination of the block range of ultrasound-guided lumbar erector spinal plane and its application in lumbar spine surgery].

Objective: To determinate the block range of lumbar erector spinal plane (ESPB), and investigate the efficacy of ESPB in lumbar spine surgery. Methods: Forty patients who underwent posterior lumbar fusion in the Second Affiliated Hospital of Wenzhou Medical University from November 2019 to August 2020 were randomly divided into two groups (with n=20 in each group) using the random number table: the experimental group (group E) and control group (group C). All the patients received ultrasound-guided bilateral ESPB with 20 ml of 0.375% ropivacaine (group E) or equal volume of normal saline (group C) on each side before induction of general anesthesia. The range of weakened temperature sense in each patient was measured at 10 min, 20 min and 30 min after ESPB, respectively. Dosage of analgesic drug, visual analog scale (VAS), and incidence of adverse events were recorded and compared between the two groups. Results: In group E, the dermatomal distribution and area of weakened temperature sense at 10 min, 20 min, 30 min after ESPB were T9-S1 (222±16) cm2, T8-S2 (352±22) cm2, T8-S3 (481±24) cm2, respectively. The intraoperative dosage of remifentanil in group E was (0.76±0.02) mg, which was significantly lower than that of group C (0.97±0.06) mg (P<0.05). Oxycodone consumption in group E at 0-12 h and 12-24 h after surgery was (4.9±0.4) mg and (8.4±1.2) mg, respectively, which were lower than those in group C [(14.5±2.4) mg and (19.3±2.4) mg, respectively] (both P<0.05). The VAS during rest and movement within 24 h after operation in group E were significantly lower than those in group C (both P<0.05). The passive exercise in bed in group E started at (3.3±0.3) h postoperatively, which was earlier than that in group C (4.6±0.3) h (P<0.05). Conclusion: The blocking effects of T12-S1 segment after ultrasound-guided lumbar ESPB is definite, which can effectively decrease the amounts of analgesics during and after the lumbar fusion surgery, reduce postoperative rest and exercise VAS score, and contribute to a rapid recovery of the patients.

[Clinical features and perinatal outcomes of 48 cases of pregnancy complicated with placental cystic lesions].

Objective: To investigate the clinical characteristics and perinatal outcomes of pregnancy with placental cystic lesions. Methods: A retrospective study was carried out on 48 pregnant women diagnosed as pregnancy complicated with placental cystic lesions from January 2000 to January 2020 at the Women's Hospital, Zhejiang University School of Medicine. The clinical features, pathological diagnosis and perinatal outcome were analyzed. Results: The age of 48 cases was (30±5) years, and the diagnostic gestational week of ultrasound was (24±8) weeks. Twenty-five cases in which showed a cystic mass at the fetal surface were diagnosed as placental cyst. The live birth rate was 100% (25/25) and the premature birth rate was 20% (5/25). Twenty-three cases showed "honeycomb like" cystic echo. Cystic lesions of 10 cases were located in the uterine cavity connected with the margin of the normal placenta, and finally diagnosed as hydatidiform mole and coexisting fetus (HMCF). Six cases of HMCF terminated pregnancy, and the live birth rate was 4/10, the premature delivery rate was 2/4. Cystic lesions of 13 cases were located in the placenta substance, and finally diagnosed as 4 cases of placental mesenchymal dysplasia (PMD) and 9 cases of focal chorionic edema; the live birth rate was 6/13 and the premature delivery rate was 4/6. The median hCG was lower in focal chorionic edema group [80 kU/L (60-110 kU/L)] than in the groups of HMCF [240 kU/L (180-430 kU/L)] and PMD [360 kU/L (210-700 kU/L)], and the differences were statistically significant (all P<0.01). Conclusions: For pregnancy complicated with placental cystic lesions, prenatal ultrasound should be performed to evaluate the shape, location and blood flow of the lesions. Maternal serological examination and invasive prenatal diagnosis are helpful for prenatal diagnosis and treatment. Due to the difference of perinatal outcomes, maternal and fetal complications, individualized pregnancy management should be carried out.

[Patterns of recurrence after neoadjuvant chemoradiotherapy compared with surgery alone in esophageal cancer].

Associated with improvement in survival, the neoadjuvant therapy had become the mainstay of therapy for patients with locally advanced esophageal cancer. Despite a significantly better survival, the recurrence risk after neoadjuvant therapy remains considerably high, with recurrence rate of>40%. Thus, it's important to gain a thorough understanding of the recurrence patterns for developing effective tertiary prevention and follow-up strategies. The aim of this review was to compare the patterns of recurrence in patients with esophageal cancer who received preoperative therapy followed by surgery or surgery alone. It is found that the most frequent recurrence pattern was distant metastasis in esophageal cancer regardless receipt of neoadjuvant therapy or not, and the major effect of neoadjuvant therapy appears to be an improvement in local regional disease control without a reduction in systemic. This frustrating fact may explain the poor survival of esophageal cancer patients receiving neoadjuvant therapy.

[Correlation between preoperative inflammatory biomarkers and postoperative pneumonia or long-term prognosis in patients with esophageal cancer after neoadjuvant therapy].

Objective: To examine the correlation between neutrophil-lymphocyte ratio (NLR), lymphocyte-monocyte ratio (LMR) and neutrophil-monocyte ratio (NMR) for postoperative pneumonia or long-term overall survival in patients with esophageal cancer after neoadjuvant therapy. Methods: The clinical data of 137 patients, including 111 males and 26 females, with the age of (M(QR))61(10) years (range: 45 to 75 years), undergoing radical resection of esophageal cancer after neoadjuvant therapy admitted at Department of Thoracic Surgery, West China Hospital from January 2016 to May 2019 were analyzed retrospectively. The blood routine one or two days before surgery and the occurrence of pneumonia after surgery were collected via hospital information system. The absolute count of neutrophils, lymphocytes and monocytes was recorded, to calculate NLR, LMR and NMR. The survival of patients was recorded systematically via follow-up. In the first part, the influencing factors of postoperative inflammation were analyzed, to group the patients into two groups according to the occurrence of postoperative pneumonia. χ2 test, t-test or rank-sum test were conducted for inter-group comparison. In the second part, cutoff values of inflammatory biomarkers were obtained with the receiver operating characteristic (ROC) curve and grouped, with postoperative pneumonia as endpoint criteria. Independent factors correlated with postoperative pneumonia were determined through univariate and multivariate Logistic regression analysis. In the third part, the analysis on prognosis factors was carried on, with the survival as endpoint criteria. Cutoff values of inflammatory biomarkers were obtained with X-Tile software and grouped. The survival analysis was carried on with univariate and multivariate Cox proportional hazards regression model, and the Kaplan-Meier curve was drawn finally. The results of survival analysis were verified by Log-rank test. Results: Median follow-up time was 614 (299) days (range: 382 to 1 612 days). Cutoff values of NLR, LMR, and NMR obtained via the ROC curve were 3.0, 3.9, and 6.2, respectively. According to the multivariate Logistic regression analysis, NLR>3.0 (OR=2.740, 95% CI: 1.221 to 6.152, P=0.015) and LMR>3.9 (OR=0.140, 95% CI: 0.022 to 0.890, P=0.037) were independent prognosis factors for postoperative pneumonia in patients with esophageal cancer after neoadjuvant therapy. Cutoff values of NLR, LMR, and NMR obtained with X-Tile software were 3.3, 4.2, and 7.2, respectively. Through multivariate Cox proportional risk regression analysis, late tumor ypTNM staging (8th AJCC) (HR=2.087, 95% CI:1.079 to 4.038, P=0.029), poor pathologic response (HR=2.251, 95% CI: 1.117 to 4.538, P=0.023), and LMR>4.2 (HR=0.347, 95% CI: 0.127 to 0.946, P=0.039) could be independent prognosis factors for overall survival. Kaplan-Meier survival analysis indicated that the overall survival of patients with LMR ≤4.2 was worse (P=0.002), with the 1-year overall survival rate of 82.9%, and the 1-year overall survival rate of patients with LMR>4.2 was 94.6%. Conclusion: Preoperative LMR ≤3.9 and NLR>3.0 can be considered as independent prognosis factors for postoperative pneumonia, while LMR≤4.2 as one of independent prognosis factors for overall survival.

Supramolecular Solvent Extraction-Gas Chromatography-Tandem Mass Spectrometry for Detection of Benzodiazepines in Urines.

ABSTRACT: Objective To establish a method using supramolecular solvent and gas chromatography-tandem mass spectrometry （GC-MS/MS） to analyze 9 benzodiazepines in urines. Methods Urine samples containing 9 benzodiazepines reference substance were subjected to liquid-liquid extractions with supramolecular solvent, which consisted of tetrahydrofuran and 1-hexanol. The solvent layer was evaporated to dryness by stream of nitrogen. The residue was reconstituted with methanol, and GC-MS/MS analysis was performed on it. The way of data collection was multiple reaction monitoring （MRM） mode; internal standard method was employed for quantification. Results In urine samples, when the range of mass concentration was 1-100 ng/mL for diazepam, midazolam, flunitrazepam and clozapine, 5-100 ng/mL for lorazepam and alprazolam, 2-100 ng/mL for nitrazepam and clonazepam, and 0.2-100 ng/mL for estazolam, respectively, good linearities were obtained, correlation coefficients were 0.999 1-0.999 9, the lower limits of the quantifications ranged from 0.2 to 5 ng/mL, the extraction recovery rates were 81.12%-99.52%. The intra-day precision ［relative standard deviation （RSD）］ and accuracy （bias） were lower than 9.86% and 9.51%, respectively; the inter-day precision （RSD） and accuracy （bias） were lower than 8.74% and 9.98%, respectively. Nine drugs in urine samples showed good stability at ambient temperature and -20 ℃ within 15 days. The mass concentrations of alprazolam in urine samples obtained from 8 volunteers who took alprazolam tablets orally within 8-72 h after ingestions ranged from 6.54 to 88.28 ng/mL. Conclusion The supramolecular solvent extraction GC-MS/MS method for analysis of 9 benzodiazepines in urines provided by this study is simple, fast, accurate and sensitive, which can provide technical support for monitoring of poisoning by benzodiazepines for clinical treatment and judicial identification.

Forensic Application of Next Generation Sequencing Technology in the Typing of Y Chromosome Genetic Markers.

ABSTRACT: The paternal inheritance characteristics of Y chromosome have been widely used in the forensic genetics field to detect the genetic markers in the non-recombining block, and used in the studies such as, genetic relationship identification, mixed stain detection, pedigree screen and ethnicity determination. At present, capillary electrophoresis is still the most common detection technology. The commercial detection kits and data analysis and processing system based on this technology are very mature. However, the disadvantages of traditional detection technology have gradually appeared with the rapid growth of bio-information amount, which promotes the renewal of forensic DNA typing technology. In recent years, next generation sequencing （NGS） technology has developed rapidly. This technology has been applied to various fields including forensic genetics and has provided new techniques for the detection of Y chromosome genetic markers. This article describes the current situation and application prospects of the NGS technology in forensic Y chromosome genetic markers detection in order to provide new ideas for future judicial practice.

Optical creation of a supercrystal with three-dimensional nanoscale periodicity.

Stimulation with ultrafast light pulses can realize and manipulate states of matter with emergent structural, electronic and magnetic phenomena. However, these non-equilibrium phases are often transient and the challenge is to stabilize them as persistent states. Here, we show that atomic-scale PbTiO3/SrTiO3 superlattices, counterpoising strain and polarization states in alternate layers, are converted by sub-picosecond optical pulses to a supercrystal phase. This phase persists indefinitely under ambient conditions, has not been created via equilibrium routes, and can be erased by heating. X-ray scattering and microscopy show this unusual phase consists of a coherent three-dimensional structure with polar, strain and charge-ordering periodicities of up to 30 nm. By adjusting only dielectric properties, the phase-field model describes this emergent phase as a photo-induced charge-stabilized supercrystal formed from a two-phase equilibrium state. Our results demonstrate opportunities for light-activated pathways to thermally inaccessible and emergent metastable states.

Quality estimation of non-demolition measurement with lossy atom-light hybrid interferometers.

The atom-light hybrid interferometer recently attracted much attention in the research of precision metrology for its combination of light and atomic spin wave. With the AC Stark effect and proper design, it can be applied in the scheme of quantum non-demolition (QND) measurement of photon numbers. In this work, we apply the QND criteria to the scheme and theoretically derive its explicit formulas with various losses of the atomic-light hybrid interferometer. With the formulas and actual experiment parameters, we estimate and compare the performance of the vapor-atom-based and cold-atom-based hybrid interferometer in the QND measurement, analyze the influences of different kinds of losses, and provide optimized working parameter ranges of the interferometer.