Ab-initio theory of quantum fluctuations and relaxation oscillations in multimode lasers

We present an \emph{ab-initio} semi-analytical solution for the noise spectrum of complex-cavity micro-structured lasers, including central Lorentzian peaks at the multimode lasing frequencies and additional sidepeaks due to relaxation-oscillation (RO) dynamics. In~Ref.~1, we computed the central-peak linewidths by solving generalized laser rate equations, which we derived from the Maxwell--Bloch equations by invoking the fluctuation--dissipation theorem to relate the noise correlations to the steady-state lasing properties; Here, we generalize this approach and obtain the entire laser spectrum, focusing on the RO sidepeaks. Our formulation treats inhomogeneity, cavity openness, nonlinearity, and multimode effects accurately. We find a number of new effects, including new multimode RO sidepeaks and three generalized $\alpha$ factors. Last, we apply our formulas to compute the noise spectrum of single- and multimode photonic-crystal lasers.Comment: 27 pages, 3 figure

To What Extent do Investors in a Financial Market Anchor Their Judgments? Evidence from the Hong Kong Horserace Betting Market

This paper explores the use of the anchoring and adjustment heuristic by decision makers in a financial market; in particular, the degree to which horserace bettors anchor their probability judgments on the advantage afforded by a horse‟s barrier-position. The results suggest that under certain conditions bettors anchor on barrier-position information revealed at previous race meetings, but not on the most recent race outcomes. In fact, bettors appear to use the most recent race outcomes appropriately when forming probability estimates; but only when the results are in line with their mental model of barrier-position advantage. Bettors with varying levels of expertise are shown to be subject to anchoring, although greater expertise is generally associated with less anchoring. The paper concludes that the manner and degree of anchoring in real world environ.

Radiative heat transfer in nonlinear Kerr media

We obtain a fluctuation--dissipation theorem describing thermal electromagnetic fluctuation effects in nonlinear media that we exploit in conjunction with a stochastic Langevin framework to study thermal radiation from Kerr ($\chi^{(3)}$) photonic cavities coupled to external environments at and out of equilibrium. We show that that in addition to thermal broadening due to two-photon absorption,the emissivity of such cavities can exhibit asymmetric,non-Lorentzian lineshapes due to self-phase modulation. When the local temperature of the cavity is larger than that of the external bath, we find that the heat transfer into the bath exceeds the radiation from a corresponding linear black body at the same local temperature. We predict that these temperature-tunable thermal processes can be observed in practical, nanophotonic cavities operating at relatively small temperatures

Quantitative test of general theories of the intrinsic laser linewidth

We perform a first-principles calculation of the quantum-limited laser linewidth, testing the predictions of recently developed theories of the laser linewidth based on fluctuations about the known steady-state laser solutions against traditional forms of the Schawlow-Townes linewidth. The numerical study is based on finite-difference time-domain simulations of the semiclassical Maxwell-Bloch lasing equations, augmented with Langevin force terms, and thus includes the effects of dispersion, losses due to the open boundary of the laser cavity, and non-linear coupling between the amplitude and phase fluctuations ($\alpha$ factor). We find quantitative agreement between the numerical results and the predictions of the noisy steady-state ab initio laser theory (N-SALT), both in the variation of the linewidth with output power, as well as the emergence of side-peaks due to relaxation oscillations.Comment: 24 pages, 10 figure

To what extent do investors in a financial market anchor their judgments? Evidence from the Hong Kong horserace betting market

This paper explores the use of the anchoring and adjustment heuristic by decision makers in a financial market; in particular, the degree to which horserace bettors anchor their probability judgments on the advantage afforded by a horse's barrier-position. The results suggest that under certain conditions bettors anchor on barrier-position information revealed at previous race meetings, but not on the most recent race outcomes. In fact, bettors appear to use the most recent race outcomes appropriately when forming probability estimates; but only when the results are in line with their mental model of barrier-position advantage. Bettors with varying levels of expertise are shown to be subject to anchoring, although greater expertise is generally associated with less anchoring. The paper concludes that the manner and degree of anchoring in real world environ

Different Effects of Hylocecarus Polyrhizus and Hylocecarus Undatus Extract on Reducing Total Cholesterol of Male Rattus Norvegicus Wistar Strain

A chronic ailment that is caused by excessive food consumption and a lack of physical activity, obesity is a condition that may be prevented. The tropical dragon fruit can control cholesterol levels, support the immune system, and give a natural colorant for culinary applications. In a true experimental research, sample with rats were fed red and white dragon fruit extracts to determine the amounts of cholesterol in their bodies. Spectrophotometry was used to determine the rats' blood lipid profiles, cholesterol levels, and body weight after they were fed a meal that was high in fat and contained duck egg yolk. For this study, extracts from red and white dragon fruits were administered to male Wistar rats to determine their effects on cholesterol levels. After fourteen days, both groups had a reduction in high cholesterol levels, with group 4 exhibiting the most significant drop in cholesterol levels. Additionally, the extracts decreased the levels of MDA while simultaneously increasing the levels of SOD. The most significant rise was seen in group 4, given white dragon fruit extract at 140 mg/200 gr BW daily. SPSS was utilized to analyze the effects of dragon fruit on blood cholesterol levels in experimental animals, employing the LSD technique and one-way ANOVA

Symmetry, stability, and computation of degenerate lasing modes

We present a general method to obtain the stable lasing solutions for the steady-state ab initio lasing theory (SALT) for the case of a degenerate symmetric laser in two dimensions (2D). We find that under most regimes (with one pathological exception), the stable solutions are clockwise and counterclockwise circulating modes, generalizing previously known results of ring lasers to all 2D rotational symmetry groups. Our method uses a combination of semianalytical solutions close to lasing threshold and numerical solvers to track the lasing modes far above threshold. Near threshold, we find closed-form expressions for both circulating modes and other types of lasing solutions as well as for their linearized Maxwell-Bloch eigenvalues, providing a simple way to determine their stability without having to do a full nonlinear numerical calculation. Above threshold, we show that a key feature of the circulating mode is its “chiral” intensity pattern, which arises from spontaneous symmetry breaking of mirror symmetry, and whose symmetry group requires that the degeneracy persists even when nonlinear effects become important. Finally, we introduce a numerical technique to solve the degenerate SALT equations far above threshold even when spatial discretization artificially breaks the degeneracy.United States. Army Research Office. Institute for Soldier Nanotechnologies (Grant W911NF-07-D-0004)Austrian Science Fund (Project SFB NextLite F49-P10)United States. Air Force Research Laboratory (Agreement FA8650-15-2-5220

SSI-AWARE: Self-Sovereign Identity Authenticated backup With Auditing by Remote Entities

Part 5: CybersecurityInternational audienceThe self-sovereign identity (SSI) model entails the full responsibility and sovereignty of a user regarding his identity data. This identity data can contain private data which is solely known to the user. The user himself is therefore required to manage the whole lifecycle of his private data, including the backup and restore. We show that prior work on how to backup and restore the user’s identity data does not meet the requirements of the SSI setting, and we present the first solution which does meet the requirements. Authenticated backup with auditing by remote entities (AWARE) combines SSI sustaining aspects and extends them to create a truly self-sovereign backup-and-restore protocol. In AWARE, trusted, physically met humans, called custodians, hold a secure device. Custodians with a secure device offer an offline backup possibility and a secure channel. The backup and restore are audited by commits on a publicly accessible distributed ledger. These commits are answered by auditing services which are required during restore. Only some auditing services hold relevant data for a restore. The self sovereignty of the user lies in the exclusive information which auditing services hold relevant data. AWARE  is the first backup-and-restore mechanism that fully complies with the SSI model. We perform an in-depth security-risk analysis of AWARE, showing a risk rating which is comparable to the best risk rating o related non-SSI-compliant backup-and-restore mechanisms. We instantiate the AWARE protocol with cryptographic primitives providing a high security level of 256-bit. We show its implementation feasibility by providing a simulation of AWARE, and conclude with an estimated performance analysis on a microcontoller architecture based on our simulation and implementation results in the literature