Weak-Light Ultraslow Vector Optical Solitons via Electromagnetically Induced Transparency

We propose a scheme to generate temporal vector optical solitons in a lifetime broadened five-state atomic medium via electromagnetically induced transparency. We show that this scheme, which is fundamentally different from the passive one by using optical fibers, is capable of achieving distortion-free vector optical solitons with ultraslow propagating velocity under very weak drive conditions. We demonstrate both analytically and numerically that it is easy to realize Manakov temporal vector solitons by actively manipulating the dispersion and self- and cross-phase modulation effects of the system.Comment: 4 pages, 4 figure

Fabrication and Characterization of Graphene-Barium Titanate-Graphene layered capacitors by spin coating at low processing temperatures

Barium titanate, BaTiO3 (BT), materials have been synthesized by two different routes: one ball-mill-derived (BMD) nanopowder and another precursor-derived (PCD) BT synthesis method were used separately to fabricate BT thin films on stainless steel (SS) and quartz substrates by spin coating. Then thin films from both synthesis routes were characterized by Ultraviolet-Visible-Near Infrared (UV-Vis-NIR) Spectroscopy, Field-Emission Scanning Electron Microscopy (FE-SEM), X-ray Diffractometry (XRD), Raman Spectroscopy, and Four-point collinear probe; all carried out at room temperature. Our studies revealed that the PCD synthesis process did not produce the BT phase even under the 900^0C air-annealing condition. In contrast, a homogeneous BT thin film has been formed from the BMD-BT nanopowder. The optical band gap of BMD-BT thin films was found in the 3.10 - 3.28 eV range. Finally, a Graphene-Barium Titanate-Graphene (G-BT-G) structure was fabricated on a SS substrate by spin coating at processing temperatures below 100^0C and characterized by two different pieces of equipment: a Potentiostat/Galvanostat (PG-STAT) and a Precision Impedance Analyzer (PIA). The G-BT-G structure exhibited a capacitance of 8 nF and 7.15 nF, a highest dielectric constant of 800 and 790, and a low dielectric loss of 4.5 and 5, investigated by PG-STAT and PIA equipment, respectively.Comment: 25 pages, 11 Figure

Theoretical Analysis of Tunable Single-Core Comb Filter Based on MZI

<!-- /* Font Definitions */ @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-1610611985 1107304683 0 0 159 0;} @font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:-1610611985 1073750139 0 0 159 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:""; margin-top:0in; margin-right:0in; margin-bottom:10.0pt; margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} .MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} .MsoPapDefault {mso-style-type:export-only; margin-bottom:10.0pt; line-height:115%;} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.0in 1.0in 1.0in; mso-header-margin:.5in; mso-footer-margin:.5in; mso-paper-source:0;} div.Section1 {page:Section1;} --> In this work, a theoretical analysis of single core tunable comb filter based on Mach-Zehnder (M-Z) interferometer is proposed and demonstrated. The proposed filter consists of one QWP, one HWP, one SMF and onePMF segment consists of two PMF lengths. Depending on the dynamic settings of wavelength of the input signal, refractive index and length of the fiber material, the comb filter provides the channel spacing tenability, and peak wavelength position switchability. The proposed comb filter is polarization insensitive as PMF is used

Quantum temporal correlations and entanglement via adiabatic control of vector solitons

It is shown that optical pulses with a mean position accuracy beyond the standard quantum limit can be produced by adiabatically expanding an optical vector soliton followed by classical dispersion management. The proposed scheme is also capable of entangling positions of optical pulses and can potentially be used for general continuous-variable quantum information processing.Comment: 5 pages, 1 figure, v2: accepted by Physical Review Letters, v3: minor editing and shortening, v4: included the submitted erratu

Does digital transformation matter for operational risk exposure?

Basel Committee recommends banks maintain a capital buffer for operational risk exposure based on business volumes, assuming aggressive actions for quicker business growth could increase risk exposures. We argue that technological innovations expose banks to more operational risk because technology helps increase business volume, but system failure, problems with internal processes, and disruptions from external and internal security threats are inherent to technology. Based on 10 years of data for 264 banks from 43 countries, we find that digitalized banking operation is an underlying driver of operational risk that comes with increased business volume. Banks proactively take more operational risks by increasing cyber spending to tackle FinTech competition in the digitalized economy. Digitalization could generally matter for operational risk exposure, but the natural experiment does not find cybersecurity threats per se could increase operational risks even though cybersecurity appears to be a serious threat to digital banking. The study creates new avenues for future research

Managerial ability and debt choice

Using a sample of 54,964 firm-year observations of U.S. public firms during the period 2001 to 2020, we investigate how managerial ability affects corporate debt choice. We find evidence that managerial ability is negatively associated with the use of bank debt. This finding remains robust to a battery of robustness tests, including alternative measures of managerial ability and debt choice, various econometric specifications, and a range of endogeneity tests. Using the sudden death of the CEO as an exogenous shock to the managerial ability, our difference-in-differences regression suggests a negative causal relationship between managerial ability and reliance on bank debt. Further, using advanced machine learning models, we identify that managerial ability is one of the highly influential variables in predicting firms’ debt choices. Our cross-sectional tests indicate that this relationship is more pronounced in the presence of higher information opacity, weaker corporate governance and poor financial conditions. In additional tests, we show that firms with more able managers use more unsecured debt and public debt. Taken together, our findings suggest that managerial ability matters in shaping corporate debt choice

Psychological and behavioral outcomes of social media-induced fear of missing out at the workplace

The intense proliferation of social media platforms into every facet of human lives has engaged researchers' attention towards understanding their adverse influences, referred to as the dark side of social media (DoSM) in the evolving literature. A relatively unexplored context in this regard is employees' personal use of social media during work hours and its impact on work-related outcomes. Since using social media during work hours can have implications for work performance and productivity, the lack of research in the area needs to be addressed by scholars sooner rather than later. Specifically, it is important to understand the drivers and outcomes of such behaviour. We have thus conceptualized a theoretical model based on the associations among individual tendencies (exhibitionism and voyeurism), fear of missing out (FoMO), and individual-level psychological (compulsive use of social media) and behavioral (work performance decrement and procrastination) outcomes of social media use during work hours. Grounded in the stressor-strain-outcomes (SSO) framework, the hypothesized associations were tested by a path analysis of 312 responses collected from individuals working in the United States. The results confirmed significant relationships between individual tendencies and FoMO, as well as psychological and behavioural outcomes. The findings contribute to the evolving literature around DoSM in the workplace and offer useful and practical insights

The dark side of phubbing in the workplace: Investigating the role of intrinsic motivation and the use of enterprise social media (ESM) in a cross-cultural setting

Despite the increasing phenomena of supervisor phubbing (a counterproductive workplace behaviour of managers), very few studies have explored its outcomes in organisations. This study aims to bridge this gap by investigating the relationships between supervisor phubbing and key employee outcomes. We conducted two studies in cross-cultural settings. In Study 1, which was conducted in Pakistan (a collectivistic culture), we collected 370 useable responses through an online survey from the employees working in the service sector organisations. Study 2, which was conducted in the United States of America (an individualistic culture), utilised the Prolific data collection service to gather 352 responses. Our results from both studies reveal that supervisor phubbing is negatively related to employee job performance and work engagement via intrinsic motivation. Further, enterprise social media (ESM) usage in organisations moderates the relationships between supervisor phubbing and its outcomes such that these relationships are weaker for employees whose ESM usage is higher. Our work offers significant contributions to the literature on technology use at workplace as it discusses a counterproductive workplace behaviour of managers (phubbing) and that behaviour’s association with key employee outcomes in organisations while also considering the moderating role of ESM usage in organisations