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Optical chaos communication is a promising secure transmission technique because of the advantages of high speed and compatibility with existing fiber-optic systems. The deterioration of chaotic synchronization quality caused by fiber optic transmission impairments affects the quality of recovery of information, especially high-order modulated signals. Here, we demonstrate that the use of a convolutional neural network (CNN) with a bidirectional long short-term memory (LSTM) layer can reduce the decryption BER in an optical chaos communication system based on common-signal-induced semiconductor laser synchronization. The performance of a neural network is investigated as a function of network parameters and chaos synchronization coefficient. Experimental results show that the BER of 16-ary quadrature-amplitude-modulation (16QAM) signal after 100-km fiber transmission is decreased from 3.05 × 10-2 to below the soft-decision forward-error-correction (SD-FEC) threshold of 2.0 × 10-2.
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OBJECTIVE: Personalized precision medicine can be facilitated by clinically available preoperative microvascular invasion (MVI) prediction models that are reliable and postoperative MVI pathological grade-related recurrence prediction models that are accurate. In this study, we aimed to compare different mathematical models to derive the best preoperative prediction and postoperative recurrence prediction models for MVI. METHODS: A total of 143 patients with hepatocellular carcinoma (HCC) whose clinical, laboratory, imaging, and pathological data were available were included in the analysis. Logistic regression, Cox proportional hazards regression, LASSO regression with 10-fold cross-validation, stepwise regression, and random forest methods were used for variable screening and predictive modeling. The accuracy and validity of seven preoperative MVI prediction models and five postoperative recurrence prediction models were compared in terms of C-index, net reclassification improvement, and integrated discrimination improvement. RESULTS: Multivariate logistic regression analysis revealed that a preoperative nomogram model with the variables cirrhosis diagnosis, alpha-fetoprotein > 400, and diameter, shape, and number of lesions can predict MVI in patients with HCC reliably. Postoperatively, a nomogram model with MVI grade, number of lesions, capsule involvement status, macrovascular invasion, and shape as the variables was selected after LASSO regression and 10-fold cross-validation analysis to accurately predict the prognosis for different MVI grades. The number and shape of the lesions were the most common predictors of MVI preoperatively and recurrence postoperatively. CONCLUSIONS: Our study identified the best statistical approach for the prediction of preoperative MVI as well as postoperative recurrence in patients with HCC based on clinical, imaging, and laboratory tests results. This could expedite preoperative treatment decisions and facilitate postoperative management.
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We proposed and verified a scheme of chaos synchronization for integrated five-section semiconductor lasers with matching parameters. The simulation results demonstrated that the integrated five-section semiconductor laser could generate a chaotic signal within a large parameter range of the driving currents of five sections. Subsequently, chaos synchronization between two integrated five-section semiconductor lasers with matched parameters was realized by using a common noise signal as a driver. Moreover, it was found that the synchronization was sensitive to the current mismatch in all five sections, indicating that the driving currents of the five sections could be used as keys of chaotic optical communication. Therefore, this synchronization scheme provides a candidate to increase the dimension of key space and enhances the security of the system.
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Common-signal-induced laser synchronization promoted a promising paradigm of high-speed physical key distribution. Constant-amplitude and random-phase (CARP) light was proposed as the common drive signal to enhance security by reducing the correlation between the drive and the laser response in intensity. However, the correlation in light phase is not examined. Here, we numerically reveal that the correlation coefficient of the CARP light phase and the response laser intensity (denoted as CCR-φD) can reach a value close to 0.6. Effects of parameters including optical frequency detuning, and modulation depth and noise bandwidth and transparency carrier density for CARP light generation are investigated in detail. By optimizing the optical frequency, modulation depth, and noise bandwidth, respectively, CCR-φD can be reduced to 0.32, 0.18, and 0.10. In the meantime, CCR-φD can be further reduced through secondary optimizing of parameters. CCR-φD can be further reduced by increasing transparent carrier density provided response laser synchronization is achieved. This work gives a new insight about the laser synchronization induced by common CARP light, and also contributes a suggestion of security improvement for physical key distribution based on laser synchronization.
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Chaos generation from a novel single-loop dispersive optoelectronic oscillator (OEO) with a broadband chirped fiber Bragg grating (CFBG) is numerically and experimentally investigated. The CFBG has much broader bandwidth than the chaotic dynamics such that its dispersion effect rather than filtering effect dominates the reflection. The proposed dispersive OEO exhibits chaotic dynamics when sufficient feedback strength is guaranteed. Suppression of chaotic time-delay signature (TDS) is observed as the feedback strength increases. The TDS can be further suppressed as the amount of grating dispersion increases. Without compromising bandwidth performance, our proposed system extends the parameter space of chaos, enhances the robustness to modulator bias variation, and improves TDS suppression by at least five times comparing to the classical OEO. Experimental results qualitatively agree well with numerical simulations. In addition, the advantage of dispersive OEO is further verified by experimentally demonstrating random bit generation with tunable rate up to 160 Gbps.
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We numerically investigate the effects of probabilistic shaping on the performance improvement of coherent optical chaos communication. Results show that the decryption bit-error ratio (BER) of the 16-ary quadrature amplitude modulation (QAM) signal decreases upon increasing the probabilistic shaping factor. It is predicted that the BER of 10-GBd 16QAM can be decreased by one order of magnitude. On the other hand, for the forward error correction threshold of the BER, the requirement for synchronization quality is no longer strict for successful decryption. This means that probabilistic shaping improves the system's tolerance to residual synchronization error. Thus, the transmission rate can be increased by approximately 30â¼60%. The side effect of probabilistic shaping is that the valid masking coefficient range is narrowed.
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Optical chaos communication encounters difficulty in high-speed transmission due to the challenge of realizing wideband chaos synchronization. Here, we experimentally demonstrate a wideband chaos synchronization using discrete-mode semiconductor lasers (DMLs) in a master-slave open-loop configuration. The DML can generate wideband chaos with a 10-dB bandwidth of 30â GHz under simple external mirror feedback. By injecting the wideband chaos into a slave DML, an injection-locking chaos synchronization with synchronization coefficient of 0.888 is realized. A parameter range with frequency detuning of -18.75â GHz to approximately 1.25â GHz under strong injection is identified for yielding the wideband synchronization. In addition, we find it more susceptible to achieve the wideband synchronization using the slave DML with lower bias current and smaller relaxation oscillation frequency.
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Semiconductor lasers with delayed optical feedback are a promising source of optical chaos for practical applications, owing to simple configurations that are easy to integrate and synchronize. However, for traditional semiconductor lasers, the chaos bandwidth is limited by the relaxation frequency to several gigahertz. Here, we propose and experimentally demonstrate that a short-resonant-cavity distributed-feedback (SC-DFB) laser can generate broadband chaos only with simple feedback from an external mirror. The short distributed-feedback resonant cavity not only enhances laser relaxation frequency but also makes the laser mode more susceptible to external feedback. Experiments obtained a laser chaos with 33.6â GHz bandwidth and a spectral flatness of 4.5â dB. The corresponding entropy rate is estimated as more than 33.3â Gbit/s. It is believed that the SC-DFB lasers will promote development of chaos-based secure communication and physical key distribution.
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Láseres de Semiconductores , Luz , Retroalimentación , Entropía , Diseño de EquipoRESUMEN
A non-motile, rod-shaped, pink-pigmented bacterium NAR14T was isolated from coral Acropora digitifera from Daya Bay, Shenzhen, PR China. Cells were Gram-stain-negative, aerobic, catalase-positive and oxidase-negative. NAR14T grew with 0-6â% (w/v) NaCl (optimum, 2-4â%), at 10-41 °C (optimum, 28 °C) and at pH 4.0-9.5 (optimum, 5.0). The major respiratory quinone was Q-10. The predominant fatty acids (more than 10%) were summed feature 8 (65.6â%) and C16â:â0 (17.6%). The DNA G+C content of NAR14T was 73.6â%. The polar lipids of NAR14T comprised one diphosphatidylglycerol, one phosphatidylethanolamine, one phosphatidylglycerol, one phosphatidylcholine, one aminolipid and three unknown polar lipids. The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that NAR14T formed a lineage within the genus Roseomonas of the family Acetobacteraceae, and it was distinct from the most closely related species Roseomonas wooponensis JCM 19527T and Roseomonas riguiloci JCM 17520T with the 16S rRNA gene sequence similarities of 94.61 and 93.98â%, respectively. Phenotypic characteristics (physiological, biochemical and chemotaxonomic) also supported the taxonomic novelty of this isolate. Thus, NAR14T is considered to represent a novel species within the genus Roseomonas, for which the name Roseomonas acroporae sp. nov. is proposed. The type strain is NAR14T (=KCTC 92174T = MCCC 1K07275T).
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Antozoos , Methylobacteriaceae , Animales , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Ubiquinona/química , ADN Bacteriano/genética , Composición de Base , Técnicas de Tipificación Bacteriana , Análisis de Secuencia de ADN , Fosfolípidos/químicaRESUMEN
BACKGROUND Thoracic paravertebral block (TPVB) and erector spinae plane block (ESPB) are widely used in video-assisted thoracic surgery (VATS). However, they have corresponding adverse effects, including hypotension for TPVB and unpredictable injectate spread in ESPB. An optimal perioperative analgesic strategy remains controversial. We investigated the effect of ultrasound-guided combined TPVB and ESPB (CTEB) for VATS. MATERIAL AND METHODS A total of 120 patients scheduled for thoracic surgery were randomized to receive either ultrasound-guided TPVB, ESPB, or CTEB preoperatively. Postoperative analgesia was achieved with sufentanil patient-controlled intravenous analgesia. The primary outcome was the static pain score at 2 h after surgery. RESULTS The static pain score 2 h postoperatively was significantly different among the 3 groups. This difference was statistically significant for Group ESPB vs Group TPVB (P=0.004), but not for Group ESPB vs Group CTEB (P=0.767), or Group TPVB vs Group CTEB (P=0.117). Group TPVB exhibited the highest incidence of hypotension among the 3 groups. More patients experienced a sensory loss in Groups TPVB and CTEB 30 min after the block performance. Patients receiving CTEB exhibited a lower incidence of chronic pain 6 months postoperatively than those in Group ESPB. CONCLUSIONS CTEB does not enhance the analgesic effect of ESPB in patients undergoing VATS; however, it may induce a faster sensory loss after nerve block and reduce the incidence of postoperative chronic pain compared with ESPB. CTEB may also help to reduce the incidence of intraoperative hypotension compared with TPVB.
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Dolor Crónico , Hipotensión , Bloqueo Nervioso , Humanos , Cirugía Torácica Asistida por Video , Estudios Prospectivos , Analgésicos , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & controlRESUMEN
Tumors in which the microenvironment is characterized by lack of immune cell infiltration are referred as "cold tumors" and typically exhibit low responsiveness to immune therapy. Targeting the factors contributing to "cold tumors" formation and converting them into "hot tumors" is a novel strategy for improving the efficacy of immunotherapy. Adenosine, a hydrolysis product of ATP, accumulates with a significantly higher concentration in the tumor microenvironments compared with normal tissue and exerts inhibitory effects on tumor-specific adaptive immunity. Tumor cells, dendritic cells, macrophages, and T cells express abundant adenosine receptors on their surfaces. The binding of adenosine to these receptors initiates downstream signaling pathways that suppress tumor antigen presentation and immune cell activation, consequently dampening adaptive immune responses against tumors. Adenosine down-regulates the expression of major histocompatibility complex â ¡ and co-stimulatory factors on dendritic cells and macrophages, thereby inhibiting antigen presentation to T cells. Adenosine also inhibits ligand-receptor binding and transmembrane signaling on T cells, concomitantly suppressing the secretion of anti-tumor cytokines and impairing T cell activation. Furthermore, adenosine hinders effector T cell trafficking to tumor sites and infiltration by inhibiting chemokine secretion and KCa3.1 channels. Additionally, adenosine promotes the secretion of immunosuppressive cytokines, increases immune checkpoint protein expression, and enhances the activity of immunosuppressive cells, collectively curbing cytotoxic T cell-mediated tumor cell killing. Given the immunosuppressive role of adenosine in adaptive antitumor immunity, several inhibitors targeting adenosine generation or adenosine receptor blockade are currently in preclinical or clinical development with the aim of enhancing the effectiveness of immunotherapies. This review provides an overview of the inhibitory effects of adenosine on adaptive antitumor immunity, elucidate the molecular mechanisms involved, and summarizes the latest advances in application of adenosine inhibition strategies for antitumor immunotherapy.
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Adenosina , Neoplasias , Humanos , Adenosina/metabolismo , Adenosina/farmacología , Linfocitos T , Inmunidad Adaptativa , Citocinas , Neoplasias/terapia , Microambiente TumoralRESUMEN
A model construction scheme of chaotic optoelectronic oscillator (OEO) based on the Fourier neural operator (FNO) is proposed. Different from the conventional methods, we learn the nonlinear dynamics of OEO (actual components) in a data-driven way, expecting to obtain a multi-parameter OEO model for generating chaotic carrier with high-efficiency and low-cost. FNO is a deep learning architecture which utilizes neural network as a parameter structure to learn the trajectory of the family of equations from training data. With the assistance of FNO, the nonlinear dynamics of OEO characterized by differential delay equation can be modeled easily. In this work, the maximal Lyapunov exponent is applied to judge whether these time series have chaotic behavior, and the Pearson correlation coefficient (PCC) is introduced to evaluate the modeling performance. Compare with long and short-term memory (LSTM), FNO is not only superior to LSTM in modeling accuracy, but also requires less training data. Subsequently, we analyze the modeling performance of FNO under different feedback gains and time delays. Both numerical and experimental results show that the PCC can be greater than 0.99 in the case of low feedback gain. Next, we further analyze the influence of different system oscillation frequencies, and the generalization ability of FNO is also analyzed.
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Chaotic optical communication technology is considered as an effective secure communication technology, which can protect information from a physical layer and is compatible with the existing optical networks. At present, to realize long-distance chaos synchronization is still a very difficult problem, mainly because well-matched hardware cannot always be guaranteed between the transmitter and receiver. In this Letter, we introduce long short-term memory (LSTM) networks to learn a nonlinear dynamics model of an opto-electronic feedback loop, and then apply the trained deep learning model to generate a chaotic waveform for encryption and decryption at the transmitter and receiver. Furthermore, to improve the security, we establish a deep learning model pool which consists of different gain trained models and different delay trained models, and use a digital signal to drive chaos synchronization between the receiver and transmitter. The proposed scheme is experimentally verified in chaotic-encrypted 56-Gbit/s PAM-4 systems, and a decrypted performance below 7%FEC threshold (BER = 3.8×10-3) can be achieved over a 100-km fiber transmission.
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The extreme magnetoresistance (XMR) of some compounds, challenging our understanding of magnetoresistance, is an interesting topic in condensed-matter and materials physics and future device applications. Here, we reported magnetotransport and magnetic properties of the as-grown and post-annealed TaCo2Te2 single crystals. The resistivity evolution with temperature in the two TaCo2Te2 single crystals shows a metallic behavior. Below 50 K, the XMR effect for the two crystals is found, and MR values at 3 K under 9 T are about 3.72 × 103% for the as-grown TaCo2Te2 and 5.71 × 102% for the annealed samples, larger than that of the previous report. The studies on the Hall effect of the two TaCo2Te2 single crystals indicate the multiband feature with high carrier mobilities from a two-band model. Electron and hole concentrations and mobilities of as-grown samples are comparable, while for the annealed sample, the hole concentration and mobility are larger than the electron concentration and mobility. The carrier mobilities for the two TaCo2Te2 single crystals have the same order of magnitude, â¼103 cm2 V-1 s-1. The XMR effect may be from high carrier mobilities. Magnetization of the as-grown TaCo2Te2 decreases with increasing temperature, and a weaker magnetic transition at â¼150 K is observed. The annealed TaCo2Te2 shows no magnetic transition and just a paramagnetic behavior with rising temperature. These results indicate that defects/deficiencies may play an important role in magnetotransport and magnetic properties of the two TaCo2Te2 single crystals. These results are helpful in deeply understanding the XMR mechanism and magnetic properties in TaCo2Te2 and offer a way to study the magnetic properties of the XMR Co-Te system.
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BACKGROUND: Due to mTOR (mammalian/mechanistic target of rapamycin) gene-loss mice die during embryonic development, the role of mTOR in platelets has not been evaluated using gene knockout technology. METHODS: A mouse model with megakaryocyte/platelet-specific deletion of mTOR was established, and be used to evaluate the role of mTOR in platelet activation and thrombus formation. RESULTS: mTOR-/- platelets were deficient in thrombus formation when grown on low-concentration collagen-coated surfaces; however, no deficiency in thrombus formation was observed when mTOR-/- platelets were perfused on higher concentration collagen-coated surfaces. In FeCl3-induced mouse mesenteric arteriole thrombosis models, wild-type (WT) and mTOR-/- mice displayed significantly different responses to low-extent injury with respect to the ratio of occluded mice, especially within the first 40 min. Additionally, mTOR-/- platelets displayed reduced aggregation and dense granule secretion (ATP release) in response to low doses of the glycoprotein VI (GPVI) agonist collagen related peptide (CRP) and the protease-activated receptor-4 (PAR4) agonist GYPGKF-NH2; these deficiencies were overcame by stimulation with higher concentration agonists, suggesting dose dependence of the response. At low doses of GPVI or PAR agonist, the activation of αIIbß3 in mTOR-/- platelets was reduced. Moreover, stimulation of mTOR-/- platelets with low-dose CRP attenuated the phosphorylation of S6K1, S6 and Akt Ser473, and increased the phosphorylation of PKCδ Thr505 and PKCε Ser729. Using isoform-specific inhibitors of PKCs (δ, É, and α/ß), we established that PKCδ/É, and especially PKCδ but not PKCα/ß or PKCθ, may be involved in low-dose GPVI-mediated/mTOR-dependent signaling. CONCLUSION: These observations indicate that mTOR plays an important role in GPVI-dependent platelet activation and thrombus formation.
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Activación Plaquetaria , Glicoproteínas de Membrana Plaquetaria , Animales , Plaquetas , Ratones , Ratones Noqueados , Agregación Plaquetaria , Serina-Treonina Quinasas TORRESUMEN
The instability of optical phase chaos synchronization between semiconductor lasers under master-slave open-loop configuration is investigated. The phase difference between the master and slave lasers is obtained and analyzed in experiment by heterodyne detection and Hilbert transform, and in simulation by solving the rate equations. The results show that the phase difference only maintains in a short duration time and then jumps to another value. A statistical analysis shows that both duration time and jumping values are random, proving that the phase chaos synchronization is unstable. A theoretical analysis shows that the instability of phase synchronization is caused by the jumping of the external cavity mode in the master laser.
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INTRODUCTION: This study aims to analyze the permeability of intra- and peri-meningiomas regions and compare the microvascular permeability between peritumoral brain edema (PTBE) and non-PTBE using DCE-MRI. METHODS: This was a retrospective of patients with meningioma who underwent surgery. The patients were grouped as PTBE and non-PTBE. The DCE-MRI quantitative parameters, including volume transfer constant (Ktrans), rate constant (Kep), extracellular volume (Ve), and mean plasma volume (Vp), obtained using the extended Tofts-Kety 2-compartment model. Logistic regression analysis was conducted to explore the risk factor of PTBE. RESULTS: Sixty-three patients, diagnosed as fibrous meningioma, were included in this study. They were 17 males and 46 females, aged from 32 to 88 years old. Kep and Vp were significantly lower in patients with PTBE compared with those without (Kep: 0.1852 ± 0.0369 vs. 0.5087 ± 0.1590, p = 0.010; Vp: 0.0090 ± 0.0020 vs. 0.0521 ± 0.0262, p = 0.007), while there were no differences regarding Ktrans and Ve (both p > 0.05). The multivariable analysis showed that tumor size ≥10 cm3 (OR = 4.457, 95% CI: 1.322-15.031, p = 0.016) and Vp (OR = 0.572, 95%CI: 0.333-0.981, p = 0.044) were independently associated with PTBE in patients with meningiomas. CONCLUSION: DCE-magnetic resonance imaging·Meningioma·Blood vessel MRI can be used to quantify the microvascular permeability of PTBE in patients with meningioma.
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Edema Encefálico , Neoplasias Meníngeas , Meningioma , Adulto , Anciano , Anciano de 80 o más Años , Edema Encefálico/diagnóstico por imagen , Edema Encefálico/etiología , Permeabilidad Capilar , Medios de Contraste , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Neoplasias Meníngeas/diagnóstico por imagen , Meningioma/diagnóstico por imagen , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
Renal cell carcinoma (RCC) is the most common malignant kidney tumors in adults. Von Hippel-Lindau (VHL) gene is deficient in >50% of RCC cases, but the role of VHL as a potential therapeutic target in RCC has not been well established. In the present study, 9-cis-Retinoic acid, which is a potent natural agonist of retinoid X receptors (RXRs), was found to decrease the viability of VHL-proficient RCC cells, but had little effect on VHL-deficient RCC cells. In addition, it was demonstrated that VHL transcriptionally regulated RXRα in a hypoxia-inducible factor-α independent manner. Moreover, a negative correlation was observed between the expressions of VHL and RXRα in RCC tissues. Collectively, these data indicate that VHL-proficient RCC patients may be more sensitive to treatment with 9-cis-retinoic acid, which acts by regulating RXRα expression, compared with VHL-deficient RCC patients. The findings of the present study demonstrate a novel function of VHL and highlight the potential of VHL expression as a therapeutic modality for the optimized treatment of RCC patients.
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Alitretinoína/farmacología , Carcinoma de Células Renales/tratamiento farmacológico , Neoplasias Renales/tratamiento farmacológico , Receptor alfa X Retinoide/metabolismo , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/metabolismo , Antineoplásicos/farmacología , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Receptor alfa X Retinoide/agonistas , Receptor alfa X Retinoide/genética , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/genéticaRESUMEN
We propose a scheme of high-speed physical key distribution based on dispersion-shift-keying chaos synchronization in two semiconductor lasers without external feedback (response lasers), which are driven by a common external-cavity semiconductor laser (drive laser). In this scheme, the dispersion introduces a laser field beating-induced nonlinear transformation to the outputs of drive laser and renders the correlation elimination between the drive and response lasers improving the security of key distribution. Moreover, the commonly driven lasers without external feedback constitute an open-loop synchronization configuration and yield a short synchronization recovery time of a subnanosecond supporting the implementation of high-speed key distribution. With these two merits, we numerically demonstrate a 1.2 Gb/s secure key distribution with a bit error ratio below 3.8×10-3.
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We numerically demonstrate the generation of wide-band laser chaos with flat power spectrum in a 2D circular-side hexagonal resonator (CSHR) microlaser subject to long-cavity optical feedback. The bandwidth and flatness of the chaotic power spectrum are investigated under different bias currents and optical feedback rates. Under low bias current, the bandwidth under an optimized optical feedback rate increases obviously as raising bias current and the power spectrum flatten simultaneously. Under high bias current, the optimized bandwidth gradually tends toward stabilization, with corresponding flatness less than 5 dB. We compare the chaotic power spectra with small-signal modulation response (SSR) curves under different bias currents. It can be concluded that wide-band and flat SSR indicates wide-band and flat chaotic power spectrum. This work argues that we can enhance laser chaos by using a laser device with wide-band and flat SSR and simple optical feedback configuration, which is significantly beneficial to synchronization-based applications including chaos communication and key distribution.