Fullerenes with μSR

The current status ofSR results on muonium states in the pure fullerenes C₆₀ and C₇₀ is summarized. The hyperfine interaction between the unpaired electron and the muon provides unique information on the molecular dynamics and local electronic structure of the fullerenes. Recent results on the alkali doped C₆₀ series are also presented.     

Ultrasound focusing with metamaterial

Ultrasonic waves,although not audible,naturally exist at high frequencies.Ultrasound can be controlled and unitized in various scenarios.Well-known examples are bats and dolphins,which produce ultrasound and detect the reflected signal for navigating and hunting.     

γγ interactions with KLOE

Studies of γγ interactions are performed with the KLOE detector, without tagging of the outgoing e^＋e^-. The data sample is from an integrated luminosity of 240 pb^-1. It was collected at the φ-factory DAONE with e^＋e^- beams colliding at √s ≌1 GeV, below the φ resonance peak. We present preliminary results concerning the observation of the γγ→η process and the evidence for γγ→π^0π^0 production at low π^0π^0 invariant masses.     

γγ interactions with KLOE

Studies of γγ interactions are performed with the KLOE detector,without tagging of the outgoing e+e-.The data sample is from an integrated luminosity of 240 pb-1.It was collected at the φ-factory DAΦNE with e+e-beams colliding at s～(1/2) 1 GeV,below the φ resonance peak.We present preliminary results concerning the observation of the γγ→η process and the evidence for γγ→π0π0 production at low π0π0 invariant masses.     

Superadditivity with Mixed States Ensemble

Superadditivity is a special property in quantum communication theory. We present the optimal measurement for a mixed-state ensemble and calculate the amount of one-shot capacity, which is connected to the intensity of noise of the channel. Then the property of superadditivity is preserved when the mixed-state ensemble is used to transmit information.     

Quantum Cryptography with Entangled QuNits

We propose an extension of quantum key distribution based on encoding the key into quiNits, i.e. quantum statesin an iv-dimensional Hilbert space. In our protocol, we adopt asymmetric measurement scheme resulting in an efficiency higher than previous protocols and a generalized Bell inequality [Phys. Rev. Lett. 92 (2004) 130404] is employed to detect the presence of an eavesdropper Eve. We also derive the information gained by a potential eavesdropper Eve applying a cloning-based attack and the maximal error rate which measures the robustness of the protocol. The result shows that the security of our scheme increases with the dimension N.     

Quantum counterfactuality with identical particles

Quantum self-interference enables the counterfactual transmission of information, whereby the transmitted bits involve no particles traveling through the channel. In this work, we show how counterfactuality can be realized even when the self-interference is replaced by interference between identical particles. Interestingly, the facet of indistinguishability called forth here is associated with first-order coherence, and is different from the usual notion of indistinguishability associated with ...     

Adaptive synchronization with nonlinear input

This paper considers the adaptive synchronization problem of the drive—response type chaotic systems. Using a transmitted scalar signal with an unknown time-delay, a response system is constructed. By appropriately selecting the observer gain and designing the controller, synchronization can be achieved in the presence of the drive system's disturbances and unknown parameters. A well-known chaotic system, Chua's circuit, is considered as an illustrative example to demonstrate the effectiveness of the proposed approach.     

Faithful Telecloning with Multiparticle Entanglement

We study the 1→N faithful telecloning of two linear-independent states of a one-qubit system.Based on the analysis of the probabilistic cloning machine,we construct a multiparticle entangled state,and present a telecloning scheme under local operations and classical communication (LOCC).The success probability is greater than half of the optimal probability of the probabilistic cloning machine.Specifically,we show how to prepare the three-particle entangled state meeded by 1→2 telecloning under LOCC using the Greenberger-Horne-Zeilinger state as a resource.All the operations in 1→2 telecloning are within the reach of current technology.     

Sub-30 nm lithography with near-field scanning optical microscope combined with femtosecond laser

We report direct laser writing of lithography patterns with a feature width of 20±5 nm on thin photoresist film by combining a double-frequency femtosecond laser and a near-field scanning optical microscope. The obtained feature size is much smaller than the laser wavelength () and the aperture diameter (d) with a resolution of /20 and d/2, respectively. The lithography patterns were analyzed with an atomic force microscope and a scanning electron microscope. The effects of laser energy and writing speed on the feature size were investigated. The underlying physical mechanism was also discussed. PACS 07.79.Fc; 07.79.Lh; 42.70.Jk; 68.37.Hk; 81.16.Nd     

Freestanding midinfrared negative-index metamaterials with sandwich configuration perforated with square arrays of holes

Metamaterials with large-scale freestanding Ag-SU-8-Ag sandwich configuration, perforated with a square periodic array of circular holes, are fabricated. The transmittance spectra of both experiment and simulation have shown the existence of two transmittance peaks in the middle-infrared region. Numerical simulations based on the effective media method and the effective parameter retrieval procedure verify that the low-frequency transmittance peak results from the electric and the magnetic resonance associated with the negative refractive index. The influence of dielectric loss of the interlayer on transmission and negative refractive response is discussed. Numerical simulations indicate that the transmission within the negative refractive index region decreases, while the dielectric loss of interlayer increase, mainly due to the enhanced reflection. Moreover, the electric resonance mode further increases the absorption resulted from the dielectric loss of interlayer.     

Probe Amplification with or without Population Inversion in a Five-Level Atomic System with Double-Dark Resonances

We theoreticMly investigate the response of the probe amplification in a five-level atomlc system m the presence of interacting double-dark resonances disturbed by introducing an additional signal field. It is found that a large enhancement of the probe amplification with or without population inversion can be achieved by properly adjusting the strengths of the microwave driving field and the signal laser field. From viewpoint of physics, we qualitatively explain these results in terms of quantum interference and dressed states.     

The Calderón Problem with Partial Data for Conductivities with 3/2 Derivatives

We study a chain of four interacting rotors (rotators) connected at both ends to stochastic heat baths at different temperatures. We show that for non-degenerate interaction potentials the system relaxes, at a stretched exponential rate, to a non-equilibrium steady state (NESS). Rotors with high energy tend to decouple from their neighbors due to fast oscillation of the forces. Because of this, the energy of the central two rotors, which interact with the heat baths only through the external rotors, can take a very long time to dissipate. By appropriately averaging the oscillatory forces, we estimate the dissipation rate and construct a Lyapunov function. Compared to the chain of length three (considered previously by C. Poquet and the current authors), the new difficulty with four rotors is the appearance of resonances when both central rotors are fast. We deal with these resonances using the rapid thermalization of the two external rotors.     

Self-similar Solutions with Fat Tails for Smoluchowski’s Coagulation Equation with Locally Bounded Kernels

The existence of self-similar solutions with fat tails for Smoluchowski’s coagulation equation has so far only been established for the solvable kernels and the diagonal one. In this paper we prove the existence of such self-similar solutions for continuous kernels K that are homogeneous of degree ${\gamma \in (-\infty,1)}$ and satisfy K(x, y) ≤ C (x ^γ + y ^γ). More precisely, for any ${\rho \in (\gamma,1)}$ we establish the existence of a continuous weak nonnegative self-similar profile with decay ${x^{-(1{+}\rho)}}$ as x → ∞. For the proof we consider the time-dependent problem in self-similar variables with the aim to use a variant of Tykonov’s fixed point theorem to establish the existence of a stationary profile. This requires to identify a weakly compact subset that is invariant under the evolution. In our case we define a set of nonnegative measures which encodes the desired decay behaviour in an integrated form. The main difficulty is to establish the invariance of the lower bound under the evolution. Our key idea is to choose as a test function in the time dependent problem the solution of the associated backward dual problem.     

On numerical integration with high-order quadratures: with application to the Rayleigh–Sommerfeld integral

The paper focusses on the advantages of using high-order Gauss?CLegendre quadratures for the precise evaluation of integrals with both smooth and rapidly changing integrands. Aspects of their precision are analysed in the light of Gauss?? error formula. Some ??test examples?? are considered and evaluated in multiple precision to $\approx $ 200 significant decimal digits with David Bailey??s multiprecision package to eliminate truncation/rounding errors. The increase of precision on doubling the number of subintervals is analysed, the relevant quadrature attribute being the precision increment. In order to exemplify the advantages that high-order quadrature afford, the technique is then used to evaluate several plots of the Rayleigh?CSommerfeld diffraction integral for axi-symmetric source fields defined on a planar aperture. A comparison of the high-order quadrature method against various FFT-based methods is finally given.     

Spread spectrum-based ultraviolet communication with experiments

We report experiments of ultraviolet （UV） communication based on spread-spectrum technique. Field measurements via online UV communication are conducted to compare the system performances with and without spectrum spreading. The results indicate that the spread-spectrum technique is capable of suppressing noise in UV atmospheric scattering channel and therefore improve the system performance evidently. Details of implementation are also provided to make the results useful for similar system design in research on optical wireless communications.     

Model with strong γ4 T-violation

We extend the T violating model of the paper on ``Hidden symmetry of the CKM and neutrino-mapping matrices" by assuming its T-violating phases χ_↑ and χ_↓ to be large and the same, with χ=χ_↑=χ_↓. In this case, the model has 9