Photon Leaking Research Articles

Super-early JWST galaxies, outflows, and Lyαvisibility in the Epoch of Reionization

The overabundance of super-early (redshiftz > 10) luminous (MUV < −20) blue galaxies detected by JWST has been explained as being due to negligible dust attenuation in these systems. We show that this model correctly reproduces the UV luminosity function atz > 10 and the star formation rate (SFR) density evolution. The model also predicts, in agreement with data, that the cosmic specific SFR (sSFR) grows as sSFR ∝ (1 + z)3/2. Atz ≃ 10, the cosmic sSFR crosses the critical value sSFR⋆ = 25 Gyr−1, and approximately 45% of the galaxies become super-Eddington, driving outflows reaching velocities of ≈830(ϵ⋆/fM)1/2km s−1, whereϵ⋆andfMare the star formation efficiency and fraction of the halo gas expelled in the outflow, respectively. This prediction is consistent with the outflow velocities measured in 12 super-Eddington galaxies of the JWST/JADES sample. Such outflows clear the dust, thus boosting the galaxy luminosity. They also dramatically enhance the visibility of the Lyαline fromz > 10 galaxies by introducing a velocity offset. The observed Lyαproperties in GN-z11 (z = 10.6) are simultaneously recovered by the outflow model if logNHI ≃ 20.1, implying that the outflow is largely ionized. We make analogous predictions for the Lyαvisibility of other super-early galaxies, and we compare the model with Lyαsurveys atz > 7, finding that essentially all super-Eddington (sub-Eddington) galaxies are (not) detected in Lyα. Finally, the sSFR positively correlates with the LyC escape fraction, as outflows carve ionized transparent channels through which LyC photons leak.

DESCRIPTION OF THE SIMPLEST NON-MARKOV PROCESS USING A DIFFERENTIAL EQUATION FOR THE QUANTUM STATE VECTOR

The Jaynes-Cummings model with one atom and a photon is considered. A photon leaks out of the cavity (optical resonator). An atom can be in an excited and ground state. Usually, the dynamics of the probability of finding a photon in a cavity is considered using the basic quantum Lindblad equation, in which the density matrix acts as an unknown function. The Lindblad equation describes a quantum Markov random process. The article attempts to replace the equation from the density matrix with an ersatz of the Lindblad equation, which is a differential equation from the state wave vector. The quantum master equation involves the use of a matrix with a dimension equal to the dimension of the state space, which increases the complexity of the calculations, since it requires a quadratically large memory. For example, for the dimension of the main space equal to a billion, the memory required to solve the basic quantum equation will be about a quintillion, which is a problem even for supercomputers. Whereas a billion-long column fits easily into the memory of a personal computer and can be easily processed on a personal laptop. The ersatz of the quantum master equation, which we are constructing, cannot accurately describe the dynamics of the density matrix and therefore cannot serve as an exact replacement for the quantum master equation. Our ersatz will describe a special process of exchange with the environment.

Enhancement of the two-photon blockade effect via Van der Waals interaction

We theoretically investigate the influence of the Van der Waals interaction on the two-photon blockade phenomenon with the corresponding photon correlation functions g(2)(0) > 1 and g(3)(0) < 1 in a two-atom cavity-QED system, where two three-level ladder-type atoms are coherently driven by a pumping field and a coupling field simultaneously. Choosing a specific frequency of the coupling field, we show the energy splitting phenomenon caused by electromagnetically induced transparency. Correspondingly, the two-photon blockade phenomenon can be achieved near the two-photon resonant frequency. Using the Van der Waals interaction between the Rydberg states of the two atoms, we also show that the two-photon blockade can be improved when two atoms radiate in-phase or out-of-phase. As a result, two photons leak from the cavity simultaneously, but the third photon is blockaded. These results presented in this study hold potential applications in manipulating photon states and generating nonclassical light sources.

Unidirectional emission and nanoparticle detection in a deformed circular square resonator.

We propose a novel deformed square resonator which has four asymmetric circular sides. Photons leak out from specific points, depending on the interplay between stable islands and unstable manifolds in phase space. By carefully breaking the mirror reflection symmetry, optical modes with strong chirality approaching 1 and unidirectional emission can be achieved simultaneously. Upon binding of a nanoparticle, the far-field emission pattern of the deformed microcavity changes drastically. Due to the EP point of the degenerate mode pairs in the deformed cavity, chirality-based far-field detection of nanoparticles with ultra-small size can be realized.

Photon leaking or very hard ionizing radiation? Unveiling the nature of He II-emitters using the softness diagram

Aims. Star-forming galaxies with nebular He II emission contain very energetic ionizing sources of radiation, which can be considered as analogs to the major contributors of the reionization of the Universe in early epochs. It is therefore of great importance to provide a reliable absolute scale for the equivalent effective temperature (T*) for these sources. Methods. We study a sample of local (z < 0.2) star-forming galaxies showing optical nebular He II emission using the so-called softness diagrams, involving emission lines of two elements in two consecutive stages of ionization (e.g., [S II]/[S III] vs. [O II]/[O III]). We use for the first time the He I/He II ratio in these diagrams in order to explore the higher range of T* expected in these objects, and to investigate the role of possible mechanisms driving the distribution of galaxy points in these diagrams. We build grids of photoionization models covering different black-body temperatures, model cluster atmospheres, and density-bounded geometries to explain the conditions observed in the sample. Results. We verified that the use of the softness diagrams including the emission-line ratio He I/He II combined with black-body photoionization models can provide an absolute scale of T* for these objects. The application of a Bayesian-like code indicates T* in the range 50−80 kK for the sample of galaxies, with a mean value higher than 60 kK. The average of these high temperature values can only be reproduced using cluster model populations with nearly metal-free stars, although such ionizing sources cannot explain either the highest T* values, beyond 1σ, or the dispersion observed in the softness diagrams. According to our photoionization models, most sample galaxies could be affected to some extent by ionizing photon leaking, presenting a mean photon absorption fraction of 26% or higher depending on the metallicity assumed for the ionizing cluster. The entire range of He I/He II, [S II]/[S III], and [O II]/[O III] ratios for these HeII-emitting galaxies is reproduced with our models, combining nearly metal-free ionizing clusters and photon leaking under different density-bounded conditions.

Strong coupling without touching

If an excited atom is put in between highreflectance mirrors, the light emitted by the atom can be bounced back and be re-absorbed and be re-emitted, again and again until the light leaks out of the mirrors or is re-emitted into a wrong direction. This coherent oscillation between atom and light, called vacuum Rabi oscillation, results from interference between two superposition states of the atom and the photon, which have different energies or frequencies, or vacuum Rabi splitting. The vacuum Rabi oscillation and splitting demonstrate the quantum nature of light. They also provide single-photon non-linearity for photonic applications. In recent years, these effects have been considered particularly useful for quantum information processing [1] since the oscillation presents a natural mechanism for information exchange between a stationary quantum bit carried by the atom and a flying quantum bit carried by the photon, making scalable and distributed quantum computing possible. Realization of the vacuum Rabi oscillation and splitting, however, is highly non-trivial. It requires the so-called strong coupling condition, that is, the exchange between the atom and the photon must be faster than the photon leaks out of the space enclosed by the mirrors, i.e. the cavity, and faster than the atom emits the light into a wrong direction. The technique to realize the strong coupling condition is to make the cavity small so that the photon is bounced back more frequently to the atom and to make the mirrors more reflective so that the photon can be bounced more times. That means to decrease the cavity volume V and to increase the quality factor Q. Remarkable progresses have been made to make optical microcavities with small V and high Q, facilitating observation of vacuum Rabi oscillation and splitting in highly dissipative solidstate systems [2,3]. However, there is no systematic method to reduce V/Q—the key factor for realizing strong coupling (see Fig. 1a). The reason appears to be fundamental. When the size of a cavity is made as small as comparable to the light wavelength, small deformation of the cavity would result in large evanescent wave and hence photon leakage [4]. A recent proposal by [5] provides a general solution, using a divide-andconquer strategy. A small cavitywith rela-

On the quantum link for transport of logic states

A novel approach for representing logic states in the quantum nodes and transferring the states from one node to another is proposed. Both transmit and receive nodes consist of a rubidium atom ( 87Rb) placed at the center of a two-mode cavity. Representation of logic states by two subspaces of the space of 87Rb atom hyperfine states eliminates the need for the transmitting node to change logic state during logic transfer through Raman process. The atom is excited by simultaneous application of two laser beams – one for each subspace. Based on the logic state, the atom emits a photon of appropriate frequency and polarization through Raman process within the corresponding subspace. The emitted photon leaks out of the cavity, reaches the receiving node, and initiates logic dependent transitions there. A simulation platform is developed through the system Hamiltonians for transmit and receive nodes followed by the formulation of the time evolution of the density matrices for the nodes. The efficacy of the simulation approach is emphasized.

Towards a novel simulation approach for the transport of atomic states through polarized photons

A novel approach for transferring logic states from one quantum node to other is proposed. Logic states ‘0’ and ‘1’ are represented by two subspaces of the hyperfine states space of rubidium atom ( 87Rb). The atom, placed at the center of a two-mode cavity, is excited by simultaneous application of two laser beams, one for each subspace. Based on the logic state of the atom, it makes a transition to a higher energy level within the corresponding subspace. When the atom relaxes back to a lower state within the subspace, a left- or right-circularly polarized photon is emitted depending on whether the initial state was logic ‘0’ or logic ‘1’. The polarized photon leaks out of the cavity, reaches the receive node and gets detected therein. Simulation results show the efficacy of the approach.

IMPLEMENTING THE ECONOMICAL 1 → M PHASE-COVARIANT QUANTUM CLONING VIA THE DETECTION OF CAVITY DECAY

We propose a scheme to realize the economical 1 → M phase-covariant quantum cloning in 2-dimension with M Λ-type three-level atoms in an optical cavity. In our scheme, we do not require addressing and exactly manipulating on every atoms, never so much as controlling the time of interaction between atoms and photon. The success or failure of cloning can be determined simply by detecting the polarization of the photon leaking out of the cavity. With the use of an automatic feedback, the success probability of the scheme can be made to approach unity. And the desired output state is a superposition of different combination of two grounds states and thus is free from decoherence caused by spontaneous emission.

A NEW VIEW OF THE SUPER STAR CLUSTERS IN THE LOW-METALLICITY GALAXY SBS 0335-052

We present a study of the individual super star clusters (SSCs) in the low-metallicity galaxy SBS 0335-052 using new near-infrared (near-IR) and archival optical Hubble Space Telescope observations. The physical properties of the SSCs are derived from fitting model spectral energy distributions (SEDs) to the optical photometry, as well as from the H? and Pa? nebular emission lines. Among the clusters, we find a significant age spread that is correlated with position in the galaxy, suggesting that successive cluster formation occurred in SBS 0335-052 triggered by a large-scale disturbance traveling through the galaxy at a speed of ~35 km s?1. The SSCs exhibit I-band (~0.8??m) and near-IR (~1.6-2.1 ?m) excesses with respect to model SEDs that are fit to the optical data. We hypothesize that the I-band excess is dominated by a photoluminescent process known as Extended Red Emission; however, this mechanism cannot account for the excesses observed at longer near-IR wavelengths. From the cluster SEDs and colors, we find that the primary origin of the near-IR excess observed in the youngest SSCs (3 Myr) is hot dust emission, while evolved red supergiants dominate the near-IR light in the older (7 Myr) clusters. We also find evidence for a porous and clumpy interstellar medium surrounding the youngest, embedded SSCs: the ionized gas emission underpredicts the expected ionizing luminosities from the optical stellar continuum, suggesting that ionizing photons leak out of the immediate vicinity of the clusters before ionizing hydrogen. The corrected, intrinsic ionizing luminosities of the two SSCs younger than ~3 Myr are each ~5 ? 1052s?1, which is equivalent to each cluster hosting ~5000 O7.5 V stars. The inferred masses of these SSCs are ~106 M ?.

Scheme for Entangling Two Distant Cavity Mirrors

A scheme is presented for the generation of entangled states for two cavity mirrors. In the scheme each mirror initially in a vacuum state interacts with a weak coherent field, resulting in a photon-number dependent kick. The detection of a photon leaking from the cavities collapses the two mirrors to an entangled state.

Generation of Entangled Bloch States for Two Atomic Samples Trapped in Separated Cavities

A scheme is presented for the generation of entangled states for two atomic ensembles trapped in two distant cavities. In the scheme, each atomic sample is initially in a Bloch state and the cavity mode is initially in a coherent state with a small amplitude. The dispersive atom-cavity interaction leads to a photon-number dependent phase shift on the atomic system. The detection of a photon leaking from the cavities makes the two atomic samples collapse to an entangled Bloch state.

Determination of Sulfur Abundance in the Solar Wind

Solar chemical abundances are determined by comparing solar photospheric spectra with synthetic ones obtained for different sets of abundances and physical conditions. Although such inferred results are reliable, they are model dependent. Therefore, one compares them with the values for the local interstellar medium (LISM). The argument is that they must be similar, but even for LISM abundance determinations models play a fundamental role (i.e., temperature fluctuations, clumpiness, photon leaks). There are still two possible comparisons—one with the meteoritic values and the second with solar wind abundances. In this work we derive a first estimation of the solar wind element ratios of sulfur relative to calcium and magnesium, two neighboring low-FIP elements, using 10 years of CELIAS/MTOF data. We compare the sulfur abundance with the abundance determined from spectroscopic observations and from solar energetic particles. Sulfur is a moderately volatile element, hence, meteoritic sulfur may be depleted relative to non-volatile elements, if compared to its original solar system value.

Scheme for Teleportation of Unknown Entangled Atomic States viaCavity Decay

We present a physical scheme to teleportan unknown atomic entangled state via cavity decay. In the teleportationprocess, four-particle Greenberger–Horne–Zeilinger (GHZ) state is used asquantum channel, and two unknown entangled atoms and two of four atoms inthe four-particle GHZ state are trapped in four leaky cavities,respectively. Based on the joint detection of the photons leak out from thefour cavities, we can teleport an unknown entangled state to two otherremote atoms with certain probability and high fidelity.

Effects of photon escape on diagnostic diagrams for H II regions

In this article we first outline the mounting evidence that a significant fraction of the ionizing photons emitted by OB stars within Hii regions escape from their immediate surroundings, i.e from what is normally defined as the Hii region, and explain how an Hii region structure containing high density contrast inhomogeneities facilitates this escape. Next we describe sets of models containing inhomogeneities which are used to predict tracks in the commonly used diagnostic diagrams (based on ratios of emission lines) whose only independent variable is the photon escape fraction, . We show that the tracks produced by the models in two of the most cited of these diagrams conform well to the distribution of observed data points, with the models containing optically thick inhomogeneities (CLUMPY models) yielding somewhat better agreement than those with optically thin inhomogeneities (FF models). We show how variations in the ionization parameter U, derived from emission line ratios, could be due to photon escape, such that for a given region from which 50% of its ionizing photons leak out we would derive the same value of U as for a region with no photon escape but with an input ionizing flux almost an order of magnitude higher. This e ect will occur whether the individual inhomogeneities are optically thick or thin. Photon escape will also lead to a change in the derived value of the radiation hardness parameter, and this change di ers significantly betwen models with optically thin and optically thick clumps. Using a rather wide range of assumptions about the filling factor of dense clumps we find, for a selected set of regions observed in M 51 by D´ iaz et al. (1991) an extreme limiting range of computed photon escape fractions between near zero and 90%, but with the most plausible values ranging between 30% and 50%. We show, using oxygen as the test element, that models with di erent assumptions about the gas inhomogeneity will tend to give variations in the abundance values derived from diagnostic diagrams, but do not claim here to have a fully developed set of diagnostic tools to improve abundance determinations made in this way. We do present an important step towards an eventual improvement in abundance determinations: the combination of line ratios with the absolute H luminosity of a given Hii region, which allows us to determine the photon escape fraction, and hence resolve the degeneracy between U and . We use observational data of this type show that a large set of Hii regions in M 101 observed by Cedr´ es and Cepa (2002) all show significant photon escape with values of ranging up to 60% in the leakiest cases.

Preparation of the W State of Atoms in a SingleCavity or N Distant Cavities by Photon Interference

We suggest two schemes to generate the W state of N Λ-typethree-level atoms. In the schemes, identical N three-level atoms aretrapped in a cavity or N distant cavities. The success or failure ofthe generation of the W state can be determined by detecting thepolarization of photon leaking out of the cavity. The resultdemonstrates that the W state is free from both the cavity loss and thespontaneous emission due to the fact that the two ground states (leftand right) of the three-level atoms are stable states (or metastablestates).

Quasideterministic generation of entangled atoms in a cavity.

We present a scheme to generate a maximally entangled state of two three-level atoms in a cavity. The success or failure of the generation of the desired entangled state can be determined by detecting the polarization of the photon leaking out of the cavity. With the use of an automatic feedback, the success probability of the scheme can be made to approach unity.

Single-trapped-ion vibronic Raman laser

We propose a model for a single-trapped-ion vibronic Raman laser and study its dynamics by using quantum-trajectory methods. In our treatment, it is essential that both the cavity field of the high-finesse optical cavity and the center-of-mass vibrational motion of the trapped ion be quantized. A transition from a super-Poissonian light source to a Poissonian lasing regime is obtained by increasing the Raman coupling constant. Furthermore, we demonstrate that a nonclassical regime can be realized, where the photon statistics becomes sub-Poissonian and the photons leak out of the cavity in an antibunched manner. This is achieved by exploiting nonlinear Stark shifts inherent in the model, which depend on both the number of cavity photons and the number of vibrational quanta.