Kerr nonlinearity assisted magnetically induced transparency in cavity magnon polaritons.

We investigate optical transmission in cavity magnon polaritons and discover a complex multi-window magnetically induced transparency and a bistability with magnetic and optical characteristics. With the regulation of Kerr nonlinear effects and driven fields, a complex multi-window resonant transmission with fast and slow light effects appears, which includes transparency and absorption windows. The magnetically induced transparency and absorption can be explained by the destructive and constructive interference between different excitation pathways. Moreover, we demonstrate the bistability of magnons and photons with a hysteresis loop, where magnetic and optical bistabilities can induce and control each other. Our results pave a new way, to the best of our knowledge, for implementing a room-temperature multiband quantum memory.

Prostatic abscess due to carbapenem-resistant K. pneumonia: A case report.

RATIONALE: Due to the widespread use of broad-spectrum antibiotics, the morbidity of prostate abscesses (PA) has declined dramatically. However, under special circumstances, such as invasive procedures and immunosuppressive conditions, some patients are more likely to develop this disease. Here, we present the case of a 21-year-old man, diagnosed with PA, with a history of chronic steroid use and a long-term indwelling urinary catheter. The pathogen was confirmed as carbapenem-resistant Klebsiella pneumoniae, a rare bacterium. This case indicates that immunodeficiency and invasive catheter use may be risk factors for PA and opportunistic bacterial infections. PATIENT CONCERNS: A 21-year-old young man presented with sudden onset of high fever (39.7°C). The patient had a history of long-term use of steroids and long-term indwelling urinary catheter. Digital rectal examination revealed obvious swelling and tenderness of the prostate. Subsequent pelvic magnetic resonance imaging showed a high signal lesion measuring 2.1 × 2.9 × 2.8 cm with T1 enhancement and T2 enhancement. DIAGNOSES: On the 8th day of hospitalization, the patient underwent a PA drainage procedure and a pus culture was conducted. Subsequent pus and urine cultures showed the presence of Klebsiella pneumoniae, which exhibited resistance to all injectable carbapenems, cephalosporins, aminoglycosides, piperacillin-tazobactam, and quinolone drugs. INTERVENTIONS: On the 8th day of hospitalization, the patient underwent PA drainage surgery under general anesthesia to drain the abscess and relieve obstruction. After the surgery, the patient received a 2-week treatment of doxycycline. OUTCOMES: Finally, the patient was discharged after recovery and did not experience recurrence during the 6-month follow-up period. LESSONS: PA is not commonly found, but some patients are more susceptible to this disease under certain host conditions. Immunodeficiency and invasive catheter use may be risk factors for PA and opportunistic bacterial infections. The use of omadacycline for the treatment of carbapenem-resistant Klebsiella pneumoniae infections appears to be effective.

Nonlinear Landau-Zener-Stückelberg-Majorana tunneling and interferometry of extended Bose-Hubbard flux ladders.

The nonlinear Landau-Zener-Stückelberg-Majorana (LZSM) tunneling dynamics and interferometry of an extended Bose-Hubbard flux ladder are studied. Based on the mean-field theory, the dispersion relation of the system is given, and it is found that loop structures periodically appear in the band structure and the nonlinear LZSM interference occurs naturally without Floquet engineering, which can be effectively modulated by atomic interactions. The nonlinear energy bands and the unique chirality feature of the flux ladder system can be identified through the dynamics of nonlinear Landau-Zener tunneling. Remarkably, the critical position of the noise in the interference pattern can be employed to identify the loop structure in the energy band, establishing an effective link between the nonlinear loop structure and LZSM interferometry. The position, intensity, symmetry, and width of interference patterns strongly depend on the magnetic field, atomic interactions, rung-to-leg coupling ratio, and energy bias, which provides an effective way to measure these parameters using the nonlinear LZSM interferometry. This paper further expands the dynamics of flux ladder systems to complex interaction regions and has potential applications in the precise measurement of related nonlinear systems.

Response to programmed cell death protein 1 antibody in patients with Epstein-Barr virus-associated intrahepatic cholangiocarcinoma.

AIM: Epstein-Barr virus-associated intrahepatic cholangiocarcinoma (EBVaICC) has a distinct genomic profile and increased CD3+ and CD8+ T cells infiltration. However, the efficacy of immunotherapy in EBVaICC remains largely unknown. This study aimed to assess the efficacy of programmed cell death protein 1 (PD-1) antibody therapy in EBVaICC. METHODS: Patients with metastatic biliary tract cancer (BTC) diagnosed at Sun Yat-sen University Cancer Center from January 2016 to December 2021 were identified. In situ hybridisation was performed to detect EBV. Overall survival (OS) and progression-free survival (PFS) were measured. RESULTS: A total of 698 patients with metastatic BTC were identified, of whom 39 (5.6%) had EBVaICC. Among the 136 patients who were not administered PD-1 antibody, the OS was similar between patients with EBVaICC and EBV-negative ICC (median OS 12.5 versus 9.5 months, respectively; P = 0.692). For the 205 patients who were administered PD-1 antibody, patients with EBVaICC had significantly longer OS than patients with EBV-negative ICC (median OS 24.9 versus 11.9 months, respectively; P = 0.004). Seventeen patients with EBVaICC were administered PD-1 antibody. Eight patients (47%) achieved a partial response, and 17 patients achieved disease control. The median PFS was 17.5 months. CONCLUSIONS: This study identified a clinically actionable subset of patients with EBVaICC with a promising response to the PD-1 antibody.

Photonic transistor based on a coupled-cavity system with polaritons.

We investigate the transmission of probe fields in a coupled-cavity system with polaritons and propose a theoretical schema for realizing a polariton-based photonic transistor. When probe light passes through such a hybrid optomechanical device, its resonant point with Stokes or anti-Stokes scattered effects, intensity with amplification or attenuation effects, as well as group velocity with slow or fast light effects can be effectively controlled by another pump light. This controlling depends on the exciton-photon coupling and single-photon coupling. We also discover an asymmetric Fano resonance in transparency windows under the strong exciton-photon coupling, which is different from general symmetric optomechanically induced transparency. Our results open up exciting possibilities for designing photonic transistors, which may be useful for implementing polariton integrated circuits.

Predictive value of prognostic nutritional and systemic immune-inflammation indices for patients with microsatellite instability-high metastatic colorectal cancer receiving immunotherapy.

Background: The prognostic nutritional index (PNI) and systemic immune-inflammation index (SII) are indicators of nutritional immune status. They have been reported associated with clinical outcomes of various solid tumors. However, it is unclear whether they can serve as predictors for patients with microsatellite instability-high (MSI-H) metastatic colorectal cancer (mCRC) receiving immunotherapy. Our objective was to study the prognostic value of PNI and SII in these patients. Methods: Seventy-five MSI-H mCRC patients were enrolled in our study. Logistic regression analysis was used to identify features that influenced immunotherapy response. Survival differences between groups of mCRC patients were compared using the Kaplan-Meier method and log-rank test. The independent risk parameters for progression-free survival (PFS) and overall survival (OS) of patients with MSI-H mCRC were established by Cox proportional risk regression analysis. Results: The optimal SII and PNI cutoff values were 409.6 and 51.35. Higher PNI (p = 0.012) and lower high-density lipoprotein cholesterol (HDLC, p = 0.012) were associated with a better immunotherapy response. SII (p = 0.031), cholesterol (CHO) (p = 0.007) and aspartate aminotransferase (AST) (p = 0.031) were independent prognostic factors correlated with OS. Higher PNI (p = 0.012) and lower AST (p = 0.049) were negative predictors of PFS. In addition, patients suffered from immune-related adverse events (irAEs) had a lower SII level (p = 0.04). Conclusion: Higher AST and SII, and lower PNI predict worse outcomes in MSI-H mCRC patients undergoing immunotherapy. Moreover, patients with lower SII before immunotherapy suffered from irAEs more often.

The Proteome Landscape of Human Placentas for Monochorionic Twins with Selective Intrauterine Growth Restriction.

In perinatal medicine, intrauterine growth restriction (IUGR) is one of the greatest challenges. The etiology of IUGR is multifactorial, but most cases are thought to arise from placental insufficiency. However, identifying the placental cause of IUGR can be difficult due to numerous confounding factors. Selective IUGR (sIUGR) would be a good model to investigate how impaired placentation affects fetal development, as the growth discordance between monochorionic twins cannot be explained by confounding genetic or maternal factors. Herein, we constructed and analyzed the placental proteomic profiles of IUGR twins and normal cotwins. Specifically, we identified a total of 5481 proteins, of which 233 were differentially expressed (57 up-regulated and 176 down-regulated) in IUGR twins. Bioinformatics analysis indicates that these differentially expressed proteins (DEPs) are mainly associated with cardiovascular system development and function, organismal survival, and organismal development. Notably, 34 DEPs are significantly enriched in angiogenesis, and diminished placental angiogenesis in IUGR twins has been further elaborately confirmed. Moreover, we found decreased expression of metadherin (MTDH) in the placentas of IUGR twins and demonstrated that MTDH contributes to placental angiogenesis and fetal growth in vitro. Collectively, our findings reveal the comprehensive proteomic signatures of placentas for sIUGR twins, and the DEPs identified may provide in-depth insights into the pathogenesis of placental dysfunction and subsequent impaired fetal growth.

Stability of trapped Bose-Einstein condensate under a density-dependent gauge field.

We study the ground-state stability of the trapped one-dimensional Bose-Einstein condensate under a density-dependent gauge field by variational and numerical methods. The competition of density-dependent gauge field and mean-field atomic interaction induces the instability of the ground state, which results in irregular dynamics. The threshold of the gauge field for exciting the instability is obtained analytically and confirmed numerically. When the gauge field is less than the threshold, the system is stable, and the gauge field induces chiral dynamics of the wave packet. When the gauge field is greater than the threshold, the system is unstable, and the ground-state wave packet will be deformed and fragmented. Interestingly, we find that as the gauge field approaches the threshold, strong dipolar and breathing dynamics take place, and strong modes mixing occurs, the instability of the system sets in. In addition, we show that the stability of the system can be well controlled by periodical modulation of the trapping potential. We provide theoretical evidence to understand and control the irregular dynamics associated with chiral superfluid induced by density-dependent gauge field.

Construction and comprehensive analysis of a novel prognostic signature associated with pyroptosis molecular subtypes in patients with pancreatic adenocarcinoma.

Background: Treatment of cancer with pyroptosis is an emerging strategy. Molecular subtypes based on pyroptosis-related genes(PRGs) seem to be considered more conducive to individualized therapy. It is meaningful to construct a pyroptosis molecular subtypes-related prognostic signature (PMSRPS) to predict the overall survival (OS) of patients with pancreatic adenocarcinoma(PAAD) and guide treatment. Methods: Based on the transcriptome data of 23 PRGs, consensus clustering was applied to divide the TCGA and GSE102238 combined cohort into three PRGclusters. Prognosis-related differentially expressed genes(DEGs) among PRGclusters were subjected to LASSO Cox regression analysis to determine a PMSRPS. External cohort and in vitro experiments were conducted to verify this PMSRPS. The CIBERSORT algorithm, the ESTIMATE algorithm and the Immunophenoscore (IPS) were used to analyze the infiltrating abundance of immune cells, the tumor microenvironment (TME), and the response to immunotherapy, respectively. Wilcoxon analysis was used to compare tumor mutational burden (TMB) and RNA stemness scores (RNAss) between groups. RT-qPCR and in vitro functional experiments were used for evaluating the expression and function of SFTA2. Results: Based on three PRGclusters, 828 DEGs were obtained and a PMSRPS was subsequently constructed. In internal and external validation, patients in the high-risk group had significantly lower OS than those in the low-risk group and PMSRPS was confirmed to be an independent prognostic risk factor for patients with PAAD with good predictive performance. Immune cell infiltration abundance and TME scores indicate patients in the high-risk group have typical immunosuppressive microenvironment characteristics. Analysis of IPS suggests patients in the high-risk group responded better to novel immune checkpoint inhibitors (ICIs) than PD1/CTLA4. The high-risk group had higher TMB and RNAss. In addition, 10 potential small-molecule compounds were screened out. Finally, we found that the mRNA expression of SFTA2 gene with the highest risk coefficient in PMSRPS was significantly higher in PAAD than in paracancerous tissues, and knockdown of it significantly delayed the progression of PAAD. Conclusions: PMSRPS can well predict the prognosis, TME and immunotherapy response of patients with PAAD, identify potential drugs, and provide treatment guidance based on individual needs.

Construction of cyclopenta[b]dihydronaphthofurans via TsOH-catalyzed consecutive biscyclization of dithioallylic alcohols and 1-styrylnaphthols.

An efficient TsOH-catalyzed consecutive biscyclization cascade reaction of dithioallylic alcohols with 1-styrylnaphthols is demonstrated for the concise construction of pharmaceutically important cyclopenta[b]dihydrobenzofuran scaffolds. This process involved an acid-catalyzed (3+2) cycloaddition followed by an intramolecular nucleophilic addition, providing cyclopenta[b]dihydronaphthofurans bearing a tetra- or fully substituted cyclopentane core in good yields with exclusive diastereoselectivities (>20 : 1 d.r.).

Nonlinear Bloch dynamics and spin-wave generation in a Bose-Hubbard ladder subject to effective magnetic field.

The two-leg magnetic ladder is the simplest and ideal model to reflect the coupling effects of lattice and magnetic field. It is of great significance to study some novel phases, topological characteristics, and chiral characteristics in condensed matter physics. In particular, the left-right leg degree of freedom can be regarded as a pseudospin, and the two-leg magnetic ladder also provides an ideal platform for the study of spin dynamics. Here the ground state, Bloch oscillations (BOs), and spin dynamics of the interacting two-leg magnetic ladder subject to an external linear force are studied by using variational approach and numerical simulation. In the absence of the external linear force, the critical condition of transition between the zero-momentum state and plane-wave state is obtained analytically, and the physical mechanism of the ground-state transition is revealed. When the external linear force presents, the occurrence of BOs excites the spin dynamics, and we reveal the chiral BOs and the accompanied spin dynamics of the system in different ground states. In particular, we further study the influence of periodically modulated linear force on BOs and spin dynamics. The frequencies of the linear force corresponding to the resonances and pseudoresonances are obtained analytically, which result in rich nonlinear dynamics. In resonances, stable and strong BOs (with larger amplitude) are observed. In pseudoresonances, because the pseudoresonance frequencies are related to the initial momentum and phase of the wave packet, a dispersion effect takes place and strong diffusion of wave packet occurs. When the frequency is nonresonant, drift and weak dispersion of wave packet occur simultaneously with the wave-packet oscillation. In all cases, the wave-packet dynamics is accompanied with periodic but anharmonic pseudospin oscillation. The BOs and spin dynamics are effectively controlled by periodically modulating the linear force.

A biodegradable 3D woven magnesium-based scaffold for orthopedic implants.

Porous Magnesium (Mg) is a promising biodegradable scaffold for treating critical-size bone defects, and as an essential element for human metabolism, Mg has shown sufficient biocompatibility. Its elastic moduli and yield strengths are closer to those of cortical bone than common, inert metallic implants, effectively reducing stress concentrations around host tissue as well as stress shielding. More importantly, Mg can degrade and be absorbed in the human body in a safe and controlled manner, thereby reducing the need for second surgeries to remove implants. The development of porous Mg scaffolds via conventional selective laser melting techniques has been limited due to Mg's low boiling point, high vapor pressures, high reactivity, and non-ideal microstructures in additively manufactured parts. Here we present an exciting alternative to conventional additive techniques: 3D weaving with Mg wires that have controlled chemistries and microstructures. The weaving process offers high throughput manufacturing as well as porous architectures that can be optimized for stiffness and porosity with topology optimization. Once woven, we dip-coat the weaves with polylactic acid to enhance their strength and corrosion resistance. Following fabrication, we characterize their mechanical properties, corrosion behavior, and cell compatibilityin vitro, and we use an intramuscular implantation model to evaluate theirin vivocorrosion behavior and tissue response.

Maresin-2 alleviates allergic airway inflammation in mice by inhibiting the activation of NLRP3 inflammasome, Th2 type immune response and oxidative stress.

Asthma is a chronic inflammatory disease of the respiratory system. Maresin-2 (MaR2) is biosynthesized from docosahexaenoic acid (DHA) by macrophages, display strong anti-inflammatory and pro-resolving activity. To investigate the therapeutic effect and mechanism of MaR2 on asthmatic mice induced by ovalbumin (OVA) in conjunction with the adjuvant aluminum hydroxide. Twenty four female BALB/c mice were randomly divided into control, OVA, OVA + MaR2, and OVA + dexamethasone (Dexa) groups. MaR2 or Dexa were given as a treatment for OVA-induced asthma. Serum, bronchoalveolar alveolar lavage fluid (BALF) and lung tissue were collected for further analysis. The Pathological changes of lung tissue, proportion of inflammatory cells in BALF, levels of inflammatory cytokines in BALF or serum, oxidative stress indices, and the protein concentration of ASC, MPO, Ly-6G, ICAM-1, NLRP3 and Caspase-1 in lung tissues were evaluated. Compared with the OVA group, both OVA + MaR2 and OVA + Dexa group had reduced inflammation and mucus secretion in lung tissue, number of inflammatory cells in BALF, levels of related inflammatory cytokines in serum or BALF, and expressions of ASC, MPO, Ly-6G, ICAM-1, NLRP3 and Caspase-1 proteins in lung tissue. In addition, the oxidative stress was alleviated as indicated by decreased MDA, and elevated SOD and GSH. MaR2 has an obvious protective effect on OVA-induced bronchial asthma in mice, in a similar manner as Dexa. The mechanism may be related to the inhibition of the Th2 type immune response, the NLRP3 inflammasome activation and oxidative stress.

Construction of a Novel LncRNA Signature Related to Genomic Instability to Predict the Prognosis and Immune Activity of Patients With Hepatocellular Carcinoma.

Background: Genomic instability (GI) plays a crucial role in the development of various cancers including hepatocellular carcinoma. Hence, it is meaningful for us to use long non-coding RNAs related to genomic instability to construct a prognostic signature for patients with HCC. Methods: Combining the lncRNA expression profiles and somatic mutation profiles in The Cancer Genome Atlas database, we identified GI-related lncRNAs (GILncRNAs) and obtained the prognosis-related GILncRNAs through univariate regression analysis. These lncRNAs obtained risk coefficients through multivariate regression analysis for constructing GI-associated lncRNA signature (GILncSig). ROC curves were used to evaluate signature performance. The International Cancer Genomics Consortium (ICGC) cohort, and in vitro experiments were used for signature external validation. Immunotherapy efficacy, tumor microenvironments, the half-maximal inhibitory concentration (IC50), and immune infiltration were compared between the high- and low-risk groups with TIDE, ESTIMATE, pRRophetic, and ssGSEA program. Results: Five GILncRNAs were used to construct a GILncSig. It was confirmed that the GILncSig has good prognostic evaluation performance for patients with HCC by drawing a time-dependent ROC curve. Patients were divided into high- and low-risk groups according to the GILncSig risk score. The prognosis of the low-risk group was significantly better than that of the high-risk group. Independent prognostic analysis showed that the GILncSig could independently predict the prognosis of patients with HCC. In addition, the GILncSig was correlated with the mutation rate of the HCC genome, indicating that it has the potential to measure the degree of genome instability. In GILncSig, LUCAT1 with the highest risk factor was further validated as a risk factor for HCC in vitro. The ESTIMATE analysis showed a significant difference in stromal scores and ESTIMATE scores between the two groups. Multiple immune checkpoints had higher expression levels in the high-risk group. The ssGSEA results showed higher levels of tumor-antagonizing immune cells in the low-risk group compared with the high-risk group. Finally, the GILncSig score was associated with chemotherapeutic drug sensitivity and immunotherapy efficacy of patients with HCC. Conclusion: Our research indicates that GILncSig can be used for prognostic evaluation of patients with HCC and provide new insights for clinical decision-making and potential therapeutic strategies.

Proteomic analysis reveals the molecular mechanism underlying the cold acclimation and freezing tolerance of wheat (Triticum aestivum L.).

Cold acclimation (CA) is an important evolutionary adaptive mechanism for wheat freezing resistence. To clarify the molecular basis of wheat CA and freezing tolerance, the effects of CA (4 °C) and non-CA (20 °C) treatments and freezing stress (-5 °C) on the proteins in the wheat crown were characterized via an iTRAQ-based proteomic analysis. A total of 669 differentially accumulated proteins (DAPs) were identified after the CA, of which seven were also DAPs in the CA plants exposed to freezing stress. Additionally, the 15 DAPs in the CA group and the 23 DAPs in the non-CA group after the freezing treatment differed substantially. Functional analyses indicated that CA enhanced freezing tolerance by regulating proteins involved in signal transduction, carbohydrate metabolism, stress and defense responses, and phenylpropanoid biosynthesis. An integrated transcriptomic, proteomic, and metabolomic analysis revealed significant changes in various components of the glutathione metabolic pathway. The overexpression and silencing of Wdhn13 in Arabidopsis and wheat resulted in increased tolerance and sensitivity to freezing stress, respectively, suggesting Wdhn13 promotes freezing tolerance. Overall, our study offers insights into the regulatory network underlying the CA and freezing tolerance of wheat, which may be useful for elucidating wheat freezing resistance.

Mechanism of circZNF609 targeting miR-153 to regulate the proliferation and apoptosis of diffuse large B-cell lymphoma / 中华肿瘤杂志

Objective: To investigate the molecular mechanism of circZNF609 targeting miR-153 to regulate the proliferation and apoptosis of diffuse large B-cell lymphoma. Methods: Fifty cases of lymphoma tissue from patients with diffuse large B-cell lymphoma who were diagnosed and treated in the First Affiliated Hospital of Zhengzhou University from July 2018 to December 2019 were collected. Thirty cases of normal lymph node tissues that were confirmed to be reactive hyperplasia by pathological diagnosis during the same period were selected as controls. Real time quantitative polymerase chain reaction (PCR) was used to detect the expression of circZNF609 in diffuse large B-cell lymphoma tissues and control hyperplasia lymph nodes. Diffuse large B-cell lymphoma OCI-LY19 cells were divided into control group (blank control), si-con group (transfected with siRNA control), si-ZNF609 group (transfected with circZNF609 siRNA), and si-ZNF609+ Anti-NC group (co-transfected with circZNF609 siRNA and inhibitor control) and si-ZNF609+ Anti-miR-153 group (co-transfected with circZNF609 siRNA and miR-153 inhibitor). Cell counting kit-8 (CCK-8) was used to detected proliferation, flow cytometry was used to detect cell cycle and apoptosis. Western blot was used to detect the protein expressions of C-caspase-3, cyclin D1, p21. The luciferase reporter system was used to identifie the relationship between circZNF609 and miR-153. Results: The expression level of circZNF609 in diffuse large B-cell lymphoma tissue was (1.44±0.22), higher than (0.37±0.14) in the control tissues (P<0.001). The cell survival rate of the si-ZNF609 group was (51.74±6.39)%, lower than (100.00±10.23)% of the control group and the (99.64±11.67)% of the si-con group (P<0.001). The proportion of cells in the G(0)/G(1) phase was (63.25±4.11)%, higher than (48.62±4.32)% of the control group and (47.12±3.20)% of the si-con group (P<0.001), the apoptosis rate was (13.36±1.42)%, higher than (3.65±0.47)% of the control group and (3.84±0.62)% of the si-con group (P<0.05). The expression levels of C-caspase-3 and p21 protein were (0.85±0.09) and (0.90±0.08), higher than (0.38±0.04) and (0.65±0.07) in the control group and (0.39±0.05) and (0.66±0.05) in the si-con group (P<0.001). The expression level of cyclin D1 protein was (0.40±0.03), lower than (0.52±0.06) of the control group and (0.53±0.04) of the si-con group (all P<0.001). CircZNF609 and miR-153 are mutually targeted. The cell survival rate of the si-ZNF609+ Anti-miR-153 group was (169.92±13.25)%, higher than (100.00±9.68)% of the si-ZNF609+ Anti-NC group (P<0.001), the ratio of cells in G(0)/G(1) phase and apoptosis rate were (52.01±3.62)% and (8.20±0.87)%, respectively, lower than (64.51±5.17)% and (14.03±1.17)% in the si-ZNF609+ Anti-NC group (P<0.001). The protein expression levels of C-caspase-3 and p21 were (0.42±0.06) and (0.52±0.06), lower than (0.80±0.07) and (0.92±0.10) of the si-ZNF609+ Anti-NC group (P<0.001). The protein expression level of cyclin D1 was (0.68±0.07), higher than (0.39±0.04) in the si-ZNF609+ Anti-NC group (P<0.001). Conclusion: Down-regulation of circZNF609 inhibits the proliferation of diffuse large B-cell lymphoma OCI-LY19 cells and induces apoptosis by targeting miR-153.

Solitary matter wave in spin-orbit-coupled Bose-Einstein condensates with helicoidal gauge potential.

We analytically and numerically study the different types of solitary wave in the two-component helicoidal spin-orbit coupled Bose-Einstein condensates (BECs). Adopting the multiscale perturbation method, we derive the analytical bright and dark solitary wave solutions of the system, and the stationary and moving bright (dark) solitary waves are obtained. The effects of spin-orbit coupling, the helicoidal gauge potential, the momentum, the Zeeman splitting, and the atomic interactions on the solitary wave types are discussed, and it is found that the coupling of these physical parameters can manipulate different types of solitary waves in the system. The results indicate that the helicoidal gauge potential breaks the symmetric properties of the energy band of the system and adjusts the energy band structure, thus further effecting the solitary wave properties, i.e., stationary or moving solitary wave, bright, or dark solitary wave. Correspondingly, the analytical predictions for exciting stationary or moving bright (dark) solitary wave in parameter space are obtained. In particular, the helicoidal gauge potential changes the solitary wave types drastically for the weak spin-orbit coupling, i.e., in the absence of the helicoidal gauge potential, only dark (bright) solitary wave solutions exist in the system with repulsive (attractive) atomic interaction; however, in the presence of the helicoidal gauge potential, both dark and bright solitary waves can exist in the system regardless of whether the atomic interaction is repulsive or attractive. In addition, we investigate the stability of solitary waves and obtain the stability regions of different types of solitary waves by applying the linear stability analysis. The dynamic evolution results of the solitary waves by the direct numerical simulation not only validate the linear stability analysis but also confirm the analytical prediction of the solitary waves. Finally, the collision effects between solitary waves are also presented by the numerical simulation. It is shown that the interactions between solitary waves in the system have both elastic and inelastic collisions, which are closely related to the position of solitary wave states in the linear energy band. Our results provide a potential way to adjust the types of solitary waves in BECs with helicoidal gauge potential.

Stability and superfluidity of the Bose-Einstein condensate in a two-leg ladder with magnetic field.

The stability and superfluidity of the Bose-Einstein condensate in two-leg ladder with magnetic field are studied. The dispersion relation and the phase diagram of the system are obtained. Three phases are revealed: the Meissner phase, the biased ladder (BL) phase, and the vortex phase. The dispersion relation and phase transition of the system strongly depend on the magnitude of atomic interaction strength, the rung-to-leg coupling ratio and the magnetic flux. Particularly, the change of the energy band structure in the phase transition region is modified significantly by the atomic interaction strength. Furthermore, based on the Bogoliubov theory, the energetic and dynamical stability of the system are invested. The stability phase diagram in the full parameter space is presented, and the dependence of superfluidity on the dispersion relation is illustrated explicitly. The atomic interaction strength can produce dynamical instability in the energetic unstable region and can expand the superfluid region. The results show that the stability of the system can be controlled by the atomic interaction strength, the rung-to-leg coupling ratio and the magnetic flux. In addition, the excitation spectrums in the Meissner phase, BL phase and vortex phase are further studied. The modulation of the excitation spectrum and the energetic stability of the system by the atomic interaction strength, the rung-to-leg coupling ratio and magnetic flux is discussed. Finally, through the numerical simulation, the dynamical instability of the system is verified by the time evolution of the Bloch wave and rung current. This provides a theoretical basis for controlling the superfluidity of the system.

Ground-state phase and superfluidity of tunable spin-orbit-coupled Bose-Einstein condensates.

We theoretically study the ground-state phases and superfluidity of tunable spin-orbit-coupled Bose-Einstein condensates (BECs) under the periodic driving of Raman coupling. An effective time-independent Floquet Hamiltonian is proposed by using a high-frequency approximation, and we find single-particle dispersion, spin-orbit-coupling, and asymmetrical nonlinear two-body interaction can be modulated effectively by the periodic driving. The critical Raman coupling characterizing the phase transition and relevant physical quantities in three different phases (the stripe phase, plane-wave phase, and zero momentum phase) are obtained analytically. Our results indicate that the boundary of ground-state phases can be controlled and the system will undergo three different phase transitions by adjusting the external driving. Interestingly, we find the contrast of the stripe density can be enhanced by the periodic driving in the stripe phase. We also study the superfluidity of tunable spin-orbit-coupled BECs and find the dynamical instability can be tuned by the periodic driving of Raman coupling. Furthermore, the sound velocity of the ground-state and superfluidity state can be controlled effectively by tuning the periodic driving strength. Our results indicate that the periodic driving of Raman coupling provides a powerful tool to manipulate the ground-state phase transition and dynamical instability of spin-orbit-coupled BECs.

Localization and spin dynamics of spin-orbit-coupled Bose-Einstein condensates in deep optical lattices.

We analytically and numerically discuss the dynamics of two pseudospin components Bose-Einstein condensates (BECs) with spin-orbit coupling (SOC) in deep optical lattices. Rich localized phenomena, such as breathers, solitons, self-trapping, and diffusion, are revealed and strongly depend on the strength of the atomic interaction, SOC, Raman detuning, and the spin polarization (i.e., the initial population difference of atoms between the two pseudospin components of BECs). The critical conditions for the transition of localized states are derived analytically. Based on the critical conditions, the detailed dynamical phase diagram describing the different dynamical regimes is derived. When the Raman detuning satisfies a critical condition, localized states with a fixed initial spin polarization can be observed. When the critical condition is not satisfied, we use two quenching methods, i.e., suddenly and linearly quenching Raman detuning from the soliton or breather state, to discuss the spin dynamics, phase transition, and wave packet dynamics by numerical simulation. The sudden quenching results in a damped oscillation of spin polarization and transforms the system to a new polarized state. Interestingly, the linear quenching of Raman detuning induces a controllable phase transition from an unpolarized phase to an expected polarized phase, while the soliton or breather dynamics is maintained.