Validation of the Chinese version of the Fear of Birth Scale among pregnant women.

AIM: Adapt Fear of Birth Scale (FOBS) for the Chinese context, evaluate psychometric properties and determine optimal cutoff point for pregnant women in 3rd trimester. DESIGN: This is a descriptive cross-sectional study. Cultural guidelines informed the development of the Chinese version of FOBS (FOBS-C) incorporating validation on translation, equivalence index, content validity index, and cognitive debriefing. Thirty pregnant women took a test-retest survey and another 1019 took three cross-sectional surveys. Convergent validation of the FOBS-C involved comparison with Childbirth Attitudes Questionnaire (CAQ), Wijma Delivery Expectancy Questionnaire (WDEQ-A), Edinburgh Postnatal Depression Scale (EPDS), Generalized Anxiety Disorder Scale (GAD-7), and physiological indicators. Cutoff points for FOBS-C were identified using receiver operating characteristic analysis against medical indicators. FINDINGS: FOBS-C demonstrated high translation equivalence (0.833-1), content validity (0.800-0.933), internal consistency (0.897), and test-retest reliability (0.860). Convergent validity was supported by statistically significant correlations between FOBS scores, heart rate, skin conductance changes, as well as scores from WDEQ-A, CAQ, EPDS, and GAD-7. Known-group validity was observed with different medical indicators. FOBS-C cutoff points indicating severe fear of childbirth were identified as 65, 68, 71, and 56, respectively, against WDEQ-A ≥ 85, CAQ ≥ 52, preference for C-section birth, and preference for analgesia, demonstrating known-group validity. A cutoff point of 65 showed the FOBS-C's strongest known-group validity. CONCLUSION: The FOBS-C exhibits robust psychometric properties, making it a valid screening tool for identifying severe fear of birth. Establishing a cutoff point at 65 facilitates effective screening.

Transcriptomic profile of premature ovarian insufficiency with RNA-sequencing.

Introduction: This study aimed to explore the transcriptomic profile of premature ovarian insufficiency (POI) by investigating alterations in gene expression. Methods: A total of sixty-one women, comprising 31 individuals with POI in the POI group and 30 healthy women in the control group (HC group), aged between 24 and 40 years, were recruited for this study. The transcriptomic profiles of peripheral blood samples from all study subjects were analyzed using RNA-sequencing. Results: The results revealed 39 differentially expressed genes in individuals with POI compared to healthy controls, with 10 upregulated and 29 downregulated genes. Correlation analysis highlighted the relationship between the expression of SLC25A39, CNIH3, and PDZK1IP1 and hormone levels. Additionally, an effective classification model was developed using SLC25A39, CNIH3, PDZK1IP1, SHISA4, and LOC389834. Functional enrichment analysis demonstrated the involvement of these differentially expressed genes in the "haptoglobin-hemoglobin complex," while KEGG pathway analysis indicated their participation in the "Proteoglycans in cancer" pathway. Conclusion: The identified genes could play a crucial role in characterizing the genetic foundation of POI, potentially serving as valuable biomarkers for enhancing disease classification accuracy.

Competent blastocyst and receptivity endometrium improved clinical pregnancy in fresh embryo transfer cycles: a retrospective cohort study.

BACKGROUND: Embryo quality is usually regarded as a key predictor of successful implantation and clinical pregnancy potential. The identification of embryos that have the capacity to implant and result in a healthy pregnancy is a crucial part of in vitro fertilization (IVF). Usually, morphologically high-quality embryos are chosen for embryo transfer in IVF treatment. The aim of this study was to assess the association between the available blastocyst formation rate and the clinical pregnancy outcome following the first fresh embryo transfer cycle and provide systematic individual treatment to adjust endometrial receptivity for the next transfer cycle. METHODS: This retrospective, single-center study included 512 fresh embryo transfers conducted between 11/2019 and 08/2021, which consisted of 385 cleavage-stage (Day 3) and 127 blastocyst-stage (Day 5) embryo transfers. The two groups were divided into a clinical pregnancy group and a nonclinical pregnancy group for comparison. The association between the available blastocyst formation rate and the clinical pregnancy rate in the Day 3 and Day 5 transfer groups were considered. RESULTS: In the Day 3 group, there were 275 clinical pregnancies, and the clinical pregnancy rate was 71.43%. Although the two pronuclei (2PN) oocyte rate and available embryo rate at Day 3 were significantly higher in the clinical pregnancy group than the nonclinical pregnancy group (P < 0.05), the blastocyst formation rate and the available blastocyst formation rate were not significantly different between the clinical pregnancy group and the nonclinical pregnancy group (P > 0.05). In the Day 5 group, there were 81 clinical pregnancies, and the clinical pregnancy rate was 63.78%. No baseline characteristics showed any obvious differences between the clinical pregnancy group and nonclinical pregnancy group (P > 0.05). The blastocyst formation rate in the nonclinical pregnancy group was higher than that in the clinical pregnancy group, but the difference was not statistically significant (81.06% vs. 77.03%, P = 0.083). Interestingly, the available blastocyst formation rate and the Day 5 available blastocyst formation rate were significantly higher in the nonclinical pregnancy group than the clinical pregnancy group (66.19% vs. 60.79%, P = 0.014; 54.58% vs. 46.98%, P = 0.007). CONCLUSIONS: In fresh cycles, the available blastocyst formation rate was not associated with the clinical pregnancy outcome for Day 3 embryo transfers, and the available blastocyst formation rate was not positively correlated with the clinical pregnancy outcome for Day 5 embryo transfers.

Effect of Day 3 cell number on the live birth rate of vitrified-warmed Day 5 single blastocyst transfer in young women.

BACKGROUND: Previous studies have reported inconsistent results regarding blastocyst selection with a high day 3 (D3) cell number and the eventual pregnancy outcomes. Thus, in this study, the relationship between the D3 cell number and clinical outcomes of day 5 single blastocyst transfer (SBT) in vitrified-warmed transfer cycles was investigated. METHODS: Our retrospective study included 1144 day 5 SBT in vitrified-warmed cycles between February 2016 and February 2021. All cycles were the first vitrified-warmed cycles, and the female patients were less than 35 years of age. Based on the D3 cell number, the cycles were divided into four groups, as follows: group A (3-7 cells, n = 130); group B (8-9 cells, n = 621); group C (10-12 cells, n = 328); and group D (13-16 cells, n = 65). The differences in the live birth rate (LBR), clinical pregnancy rate, and miscarriage rate were examined among the four groups. RESULTS: The LBR and clinical pregnancy rate increased with the D3 cell number (P < 0.01). No significant difference was found in the miscarriage rate among the groups (P = 0.055). After adjusting for confounding factors, the LBR was significantly higher in groups C (odds ratio [OR] = 1.477, 95% confidence interval [CI]: 1.124-1.941, P = 0.005) and D (OR = 2.000, 95% CI: 1.166-3.429, P = 0.012) than in group B. CONCLUSIONS: A high D3 cell number (> 9 cells) was associated with a high LBR in the vitrified-warmed day 5 SBT cycles of patients < 35 years of age. The cell number of D3 embryos can be an important reference indicator for blastocyst selection. Among blastocysts with the same morphological score, those with > 9 cells on D3 can be preferentially selected for transplantation.

A qualitative study on the caregiver burden experience in home reflux enema management of infants with congenital megacolon.

OBJECTIVE: This study aims to explore the caregiver burden experience in the care of infants with congenital megacolon undergoing home reflux enema. The findings will provide a basis for developing targeted and effective nursing interventions. METHODS: A phenomenological research approach was employed. From October 2022 to January 2023, semi-structured in-depth interviews were conducted with 12 caregivers of infants with congenital megacolon undergoing home reflux enema in a tertiary paediatric hospital in Fujian Province. The collected data were analysed and organized using the Colaizzi's 7-step analysis method, leading to the identification of key themes. RESULTS: The analysis yielded three major themes concerning the caregiver burden experience in the care of infants with congenital megacolon undergoing home reflux enema: inadequate disease-related knowledge, presence of multiple pressures during the caregiving process, and a desire for greater support. CONCLUSIONS: This study employed qualitative interviews with the caregivers of 12 children with congenital Hirschsprung's disease undergoing home reflux enema, and the feelings of caregivers of children with reflux enema at home after discharge were deeply understood. It is recommended to implement positive psychological interventions based on the PERMA model and incorporate "Internet + collaborative nursing" to provide caregivers with professional knowledge, address their pressures and needs, and promote their well-being while enhancing nursing abilities.

Polarization-stable single-mode 795†nm grating-coupled surface-emitting laser for quantum sensing.

We demonstrate a polarization-stable and single-mode grating-coupled surface-emitting laser (GCSEL) with high side-mode suppression ratio (SMSR) of ∼40 dB and orthogonal polarization suppression ratio (OPSR) of ∼25 dB around 795 nm. The fabricated devices have low threshold current of ∼4.8 mA and low electrical resistance of 53 Ω at 25 °C. Meanwhile, a low thermal resistance of ∼1 K/mW is achieved, which is comparable with that of the record of ever reported for vertical-cavity surface-emitting lasers (VCSELs). The far-field divergence angle of surface-emitting beam is ∼14.5°x14.7° at an injection current of 12 mA indicating a relatively good beam quality. Our results open what we believe is a new way to produce polarization-stable single-mode surface-emitting lasers with simple fabrication process. While the GCSEL is specifically designed for quantum sensing applications such as atomic clocks, magnetometers, and gyroscope, its performance in terms of low-power consumption, low thermal resistance, good beam qualities, and wafer-level testing are of particular interest for a wide range of applications.

Modified submandibular mandibulotomy approach versus lip-splitting approach in tongue cancer surgery: a retrospective paired-cohort study.

OBJECTIVES: The surgical approach for resection and reconstruction of tongue cancer (TSCC) with or without the lip-splitting incision is controversial. This study introduced a modified approach without lip-splitting and the clinical results were assessed. METHODS: Sixty-eight TSCC patients underwent surgery using the modified submandibular mandibulotomy (MSMM) approach without lip-splitting, and another matched 68 patients using lip-splitting mandibulotomy (LSM) approach were enrolled in this study. The clinical results including intraoperative relevance and surgical morbidities, survival status, facial appearance and scar scores, function of lower lip, and quality of life (QOL) were evaluated. RESULTS: The primary tumors were en bloc resected through the MSMM approach with excellent tumor exposure and R0 resection margins as LSM approach. The survival status and complications were similar in both groups. The function of lower lip was better in patients of MSMM group at 1 month after surgery. The MSMM approach was associated with significantly better facial appearance and recreation compared to LSM approach by scar scores and QOL assessment. CONCLUSION: The MSMM approach without lip-splitting achieves similar tumor control, better aesthetic results, and QOL compared to LSM approach. It is a safe and effective surgical approach for patients with TSCC. CLINICAL RELEVANCE: The MSMM approach without lip-splitting is oncological safety in tongue cancer surgery and is scrutinized as one part of the treatment concept for better aesthetic results.

The regulation of tolerogenic dendritic cells by a Chinese herb formula improves abortion prone in mice.

BACKGROUND: Abortion prone (AP) is a common clinical event. The underlying mechanism remains unclear. Traditional Chinese formulas are known to be efficient in the management of abortion. The purpose of this study is to observe the effects of Anzitiaochongtang (AZT), a traditional formulation of Chinese medicine, on improving AP in mice by regulating immune tolerance. METHODS: An established abortion model (CBA/J×DBA/2) was employed. AZT was prepared and administered to mice in a manner consistent with clinical practice. Tolerogenic dendritic cells (tDC) and type 1 regulatory T cells (Tr1 cell) in mice were analyzed by immunological approaches to be used as representative immune tolerant parameters. RESULTS: An AP model was established with CBA/J × DBA/2 mice. The expression of IL-10 in tDC and Tr1 cell frequency in the mouse decidua tissues were lower in the AP group than that in the normal pregnancy (NP) group. Administration of AZT up regulated the expression of IL-10 in tDCs and Tr1 cell generation in the decidua tissues, and improved the pregnancy and tissue structure in AP mice. The main mechanism by which AZT improves pregnancy in AP mice is that AZT enhanced the expression of galectin-9 in the epithelial cells of decidua tissues. Galectin 9 activates TIM3 on DCs to promote the IL-10 expression. The DCs induced more Tr1 cells in the decidua tissues. CONCLUSIONS: Dysfunctional tDCs were detected in the AP decidua tissues. Administration of AZT improved pregnancy in AP mice by regulating tDC function and generation of Tr1 cells in the maternal-fetal interface.

Beyond Fear: Unveiling the Relationship Between Fear of Childbirth and Pharmacological Pain Relief.

BACKGROUND: Pharmacological analgesia is the dominant method for pain relief in labor. Fear of childbirth (FOC) may significantly affect women's preferences for and usage of pharmacological analgesia. AIM: This study aimed to investigate the relationship between FOC in late pregnancy and preferences for, as well as actual use of, pharmacological analgesia among nulliparous and multiparous women, accounting for confounding factors. METHODS: A total of 1,300 women participated in the study, completing questionnaires assessing preferences for pharmacological analgesia, FOC, perception of labor pain, social support, coping styles, and demographic variables. The actual use of pharmacological analgesia was followed up. The data were analyzed using univariate and multivariate regression analyses. RESULTS: Univariate analysis revealed that women with moderate to severe FOC had a stronger preference for pharmacological analgesia compared to those with none to mild FOC. However, multivariate analysis showed no direct association between FOC and actual usage of pharmacological analgesia. Instead, a stronger preference for pharmacological analgesia increased the likelihood of its actual usage during labor. CONCLUSIONS: Our study underscores the effect of FOC on preferences for pharmacological analgesia and its potential influence on actual usage during labor. Healthcare providers should consider women's FOC and preferences when evaluating pain management options. Targeted interventions focusing on promoting non-pharmacological techniques should be implemented to optimize labor pain management for women, particularly nulliparous women.

Organizational display rules in nursing: Impacts on caring behaviors and emotional exhaustion through emotional labor.

AIM: To examine the impact of display rules on nurses' caring behaviors and emotional exhaustion and the mediating role of emotional labor (surface/deep acting). BACKGROUND: Hospitals often implement emotional display rules for nurses with the expectation of performance benefits. However, these rules may have an impact on nurses' caring behaviors and emotional exhaustion. METHODS: This cross-sectional correlational study included a sample of 746 nurses from five hospitals and used the STROBE checklist. Relationships between display rules, emotional labor, caring behaviors, and emotional exhaustion were analyzed using structural equation modeling. RESULTS: Display rules did not directly affect caring behaviors or emotional exhaustion. Emotional labor mediated the relationships. Display rules were associated more with surface acting. Deep acting increased caring behaviors and reduced emotional exhaustion; surface acting had the opposite effect. CONCLUSIONS: Findings challenge the assumption that display rules effectively promote caring behaviors. Display rules lead to emotional labor and emotional exhaustion. Reducing display rules, emotional labor, and surface acting while supporting deep acting may alleviate emotional exhaustion. IMPLICATIONS FOR NURSING AND HEALTH POLICY: Nurse managers should review the nature and implementation of emotional display rules and explore ways to reduce emotional labor, encourage deep acting, mitigate the negative impact of surface acting, and ultimately improve nursing caring behaviors.

Effects of an autonomy-supportive intervention programme (ASIP) on self-care, quality of life, and mental health in heart failure patients: a randomized controlled trial.

PURPOSE: Patients with heart failure (HF) possess low self-care activation and motivation, leading to a deprived quality of life and adverse mental health conditions. To this end, self-determination theory emphasizes that autonomy-supportive interventions (ASI) can stimulate intrinsic motivation and improve behaviors and quality of life. Nevertheless, studies that focused on ASI for HF are inadequate. This study aims to evaluate the effects of an HF-ASIP on self-care, quality of life and mental health in HF patients. METHODS: In a two-arm randomized controlled trial, the participants are randomly allocated to the intervention (n = 41) or control (n = 41) groups. The intervention group received routine care and participated in an 8-week HF-ASIP, including individual education and consultation sessions. In contrast, the control group received only routine care. The primary outcome includes self-care management, while the secondary outcomes include self-care maintenance, quality of life, mental health, and motivation. After measuring the outcomes at baseline (T0), 4-week (T1), 8-week (T2), and 12-week (T3) follow-up, the intervention effects are assessed using the generalized equation models. RESULTS: The outcomes indicated that self-care management (T2: P = 0.001; T3: P = 0.016), self-care maintenance (T2: P = 0.003; T3: P = 0.001), depression (T2: P = 0.007; T3: P = 0.012), anxiety (T2: P = 0.001; T3: P = 0.012), MLHFQ total score (T1: P = 0.004; T2: P < 0.001; T3: P = 0.001), autonomous motivation (T2: P = .0.006; T3: P = 0.002) showed statistically difference between the groups. CONCLUSION: In summary, the 8-week HF-ASIP significantly improved the attributes of self-care, quality of life, mental health, and motivation in HF patients, suggesting the potential for practical intervention effect. TRIAL REGISTRATION: ChiCTR2100053970.

Predictive value of serum HCG concentrations for outcomes of vitrified-warmed blastocyst transfers in women of different ages.

RESEARCH QUESTION: Can serum human chorionic gonadotrophin (HCG) concentrations on day 10 after single-blastocyst transfer (SBT) in cryopreserved transfer cycles help to predict the cycle outcome in patients of different maternal ages? DESIGN: The study included 772 vitrified-warmed SBT cycles. The initial maternal serum HCG concentrations measured on day 10 after blastocyst transfer were evaluated using receiver operating characteristic (ROC) curves to predict clinical pregnancy and live birth. Threshold values for predicting a clinical pregnancy were established in three different age groups: group A (21-29 years old, n = 360), group B (30-34 years old, n = 290) and group C (35-47 years old, n = 122). RESULTS: The areas under the ROC curves for clinical pregnancy and live birth were 0.986 and 0.922, and the corresponding cut-off values were 113.28 and 146.37 mIU/ml, respectively. The optimal threshold values for clinical pregnancy as indicated by Youden index values for the three age groups were 145.15, 126.25 and 94.44 mIU/ml, respectively. CONCLUSIONS: The study demonstrates that determination of initial serum ß-HCG concentrations on day 10 after SBT in cryopreserved transfer cycles can help to predict cycle outcome in women of different ages. The optimal threshold value for clinical pregnancy for patients over 35 years of age was lower than that for the younger age groups.

Digital PCR Detection of mtDNA/gDNA Ratio in Embryo Culture Medium for Prediction of Embryo Development Potential.

PURPOSE: The ratio of mitochondrial DNA to genomic DNA (mtDNA/gDNA) in embryo culture medium as a predictor of embryonic development is a new method of noninvasive embryo screening. However, current tests based on this concept have proven inconsistent. The aim of this study was to define the predictive value of the ratio of mtDNA/gDNA for embryonic developmental potential. MATERIALS AND METHODS: We used digital PCR to measure mtDNA/gDNA ratios in day 3 culture media of 223 embryos from 56 patients. We compared the relationship between the predictive value of mtDNA/gDNA ratio and each of embryo fragmentation, embryo morphological grade, and blastocyst formation. RESULTS: mtDNA/gDNA ratio decreased significantly with a decrease in embryo rating: 22.54 (44.66); 31.25 (36.97) and 46.33 (57.11); Grades A vs C, P = 0.006; B vs C, P = 0.015. mtDNA/gDNA ratio increased overall with an increase in embryo fragment content but did not differ significantly between high-, -medium, and poor-quality embryos. Interestingly, this trend differed from that of the unformed blastocysts. mtDNA/gDNA ratio of cleavage stage embryos forming blastocysts was lower (P=0.005). Trends of mtDNA/gDNA ratio differed according to inner cell mass (ICM) and trophectoderm (TE) levels, but not significantly. mtDNA/gDNA ratio in day 3 culture medium was not significantly improved over morphological scores. CONCLUSION: We hereby show the correlation of mtDNA/gDNA ratio in the culture medium of developing embryos. The correlation between the mtDNA/gDNA ratio and early embryonic development was controversial. Furthermore, an increase in mtDNA/gDNA ratio might indicate reduced development potential, but the difference remains insufficient for application as a clinical predictor.

Chiral graphene plasmonic Archimedes' spiral nanostructure with tunable circular dichroism and enhanced sensing performance.

Circular dichroism spectroscopy is frequently used to characterize the chiral biomolecules by measuring the absorption spectra contrast between the left-handed circularly polarized light and the right-handed circularly polarized light. Compared with biomolecules, chiral metal plasmonic nanostructures also produce a strong circular dichroism response in the range of near-infrared. However, due to the large damping rate, the non-adjustable resonant frequency of the conventional metals, the applications of chiral metal plasmonic nanostructures in the fields of photoelectric detection and chemical and biochemical sensing are restricted. Here, we present a chiral graphene plasmonic Archimedes' spiral nanostructure that displays a significant circular dichroism response under the excitation of two polarizations of circularly polarized light. By manipulating the material and geometric parameters of the Archimedes' spiral, the stronger circular dichroism responses and modulation of the resonant wavelength are achieved. The optimized plasmonic nanostructure has outstanding refractive index sensing performance, where the sensitivity and figure of merit reach 7000nm/RIU and 68.75, respectively. Our proposed chiral graphene plasmonic Archimedes' spiral nanostructure might find potential applications in the fields of optical detection and high performance of index sensing.

"Fast" Plasmons Propagating in Graphene Plasmonic Waveguides with Negative Index Metamaterial Claddings.

We propose the monolayer graphene plasmonic waveguide (MGPW), which is composed of graphene core sandwiched by two graphene metamaterial (GMM) claddings and investigate the properties of plasmonic modes propagating in the waveguide. The effective refraction index of the GMMs claddings takes negative (or positive) at the vicinity of the Dirac-like point in the band structure. We show that when the effective refraction index of the GMMs is positive, the plasmons travel forward in the MGPW with a positive group velocity (vg > 0, vp > 0). In contrast-for the negative refraction index GMM claddings-a negative group velocity of the fundamental mode (vg < 0, vp > 0) appears in the proposed waveguide structure when the core is sufficiently narrow. A forbidden band appears between the negative and positive group velocity regions, which is enhanced gradually as the width of the core increases. On the other hand, one can overcome this limitation and even make the forbidden band disappear by increasing the chemical potential difference between the nanodisks and the ambient graphene of the GMM claddings. The proposed structure offers a novel scheme of on-chip electromagnetic field and may find significant applications in the future high density plasmonic integrated circuit technique.

Multiple Fano Resonances with Tunable Electromagnetic Properties in Graphene Plasmonic Metamolecules.

Multiple Fano resonances (FRs) can be produced by destroying the symmetry of structure or adding additional nanoparticles without changing the spatial symmetry, which has been proved in noble metal structures. However, due to the disadvantages of low modulation depth, large damping rate, and broadband spectral responses, many resonance applications are limited. In this research paper, we propose a graphene plasmonic metamolecule (PMM) by adding an additional 12 nanodiscs around a graphene heptamer, where two Fano resonance modes with different wavelengths are observed in the extinction spectrum. The competition between the two FRs as well as the modulation depth of each FR is investigated by varying the materials and the geometrical parameters of the nanostructure. A simple trimer model, which emulates the radical distribution of the PMM, is employed to understand the electromagnetic field behaviors during the variation of the parameters. Our proposed graphene nanostructures might find significant applications in the fields of single molecule detection, chemical or biochemical sensing, and nanoantenna.

CCDC9 is identified as a novel candidate gene of severe asthenozoospermia.

Owing to less than 1% of motile spermatozoa in the ejaculated semen, severe asthenozoospermia is a serious threat to the male reproductive health. Herein, we identified a novel homozygous variant in CCDC9 (NC_000019.9: g.47763960C>T, NM_015603.3, NP_056418.1: p. Ser109Leu) in a patient from a consanguineous family. The variant was highly pathogenic and was predicted to be a candidate gene for asthenozoospermia through in silico analysis. The CCDC9 protein levels were significantly low and its morphology and ultrastructure were severely damaged in the spermatozoa containing the novel variant. Therefore, CCDC9 may be a novel pathogenic gene associated with severe asthenozoospermia.Abbreviations: CCDC9: coiled-coil domain containing 9; AZS: asthenozoospermia; MP: midpiece; MS: mitochondrial sheath; ODF: outer dense fiber; CP: central pair; DMT: doublet microtubule; IDA: inner dynein arm; ODA: outer dynein arm.

A flexible control on electromagnetic behaviors of graphene oligomer by tuning chemical potential.

In this work, we demonstrate that the electromagnetic properties of graphene oligomer can be drastically modified by locally modifications of the chemical potentials. The chemical potential variations of different positions in graphene oligomer have different impacts on both extinction spectra and electromagnetic fields. The flexible tailoring of the localizations of the electromagnetic fields can be achieved by precisely adjusting the chemical potentials of the graphene nanodisks at corresponding positions. The proposed nanostructures in this work lead to the practical applications of graphene-based plasmonic devices such as nanosensing, light trapping and photodetection.

Dynamic tailoring of electromagnetic behaviors of graphene plasmonic oligomers by local chemical potential.

In the mid-infrared and terahertz (THz) regime, graphene supports tunable surface plasmon resonance (SPR) by controlling the chemical potential, which promotes light-matter interaction at the selected wavelength, showing exceptional promise for optoelectronic applications. In this article, we show that the electromagnetic (EM) response of graphene oligomers can be substantially modified by the modification of the local chemical potential, strengthening or reducing the intrinsic plasmonic modes. The effect mechanism is corroborated by a graphene nanocluster composed of 13 nanodisks with D6h symmetry; by transforming to D3h symmetry, the effect mechanism was retained and more available plasmonic resonance modes appeared. The intriguing properties open a new way to design nanodevices made of graphene oligomers with highly efficient photoresponse enhancement and tunable spectral selectivity for highly accurate photodetection.

Pseudospin Dependent One-Way Transmission in Graphene-Based Topological Plasmonic Crystals.

Originating from the investigation of condensed matter states, the concept of quantum Hall effect and quantum spin Hall effect (QSHE) has recently been expanded to other field of physics and engineering, e.g., photonics and phononics, giving rise to strikingly unconventional edge modes immune to scattering. Here, we present the plasmonic analog of QSHE in graphene plasmonic crystal (GPC) in mid-infrared frequencies. The band inversion occurs when deforming the honeycomb lattice GPCs, which further leads to the topological band gaps and pseudospin features of the edge states. By overlapping the band gaps with different topologies, we numerically simulated the pseudospin-dependent one-way propagation of edge states. The designed GPC may find potential applications in the fields of topological plasmonics and trigger the exploration of the technique of the pseudospin multiplexing in high-density nanophotonic integrated circuits.