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Volume 33 Issue 01
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GENERAL
Cryptanalysis and Improvement of the Multi-User QPCE Protocol with Semi-Honest Third Party
Yan Chang, Chun-Xiang Xu, Shi-Bin Zhang, Hai-Chun Wang, Li-Li Yan, Gui-Hua Han, Yuan-Yuan Huang, Zhi-Wei Sheng
Chin. Phys. Lett. 2016, 33 (01): 010301 .   DOI: 10.1088/0256-307X/33/1/010301
Abstract   PDF(pc) (377KB) ( 524 ) PDF(mobile)(KB) ( 3 ) HTML ( 18

In a recent work [Quantum Inf. Process 12 (2013) 1077], a multi-user protocol of quantum private comparison of equality (QPCE) is presented. Here we point out that if we relax the constraint of a semi-honest third party, the private information of the users will be totally leaked out to the third party. A special attack is demonstrated in detail. Furthermore, a possible improvement is proposed, which makes the protocol secure against this kind of attack.

Connecting Quantum Contextuality and Genuine Multipartite Nonlocality with the Quantumness Witness
Xu Chen, Hong-Yi Su, Jing-Ling Chen
Chin. Phys. Lett. 2016, 33 (01): 010302 .   DOI: 10.1088/0256-307X/33/1/010302
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The Clauser–Horne–Shimony–Holt-type noncontextuality inequality and the Svetlichny inequality are derived from the Alicki–van Ryn quantumness witness. Thus connections between quantumness and quantum contextuality, and between quantumness and genuine multipartite nonlocality are established.

Analytical Solutions to the $D$-Dimensional Schrödinger Equation with the Eckart Potential
Jie Gao, Min-Cang Zhang
Chin. Phys. Lett. 2016, 33 (01): 010303 .   DOI: 10.1088/0256-307X/33/1/010303
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The analytical solutions to the Schr?dinger equation with the Eckart potential in arbitrary dimension $D$ is investigated by using the Nikiforov–Uvarov method, and the centrifugal term is treated approximatively with the scheme of Greene and Aldrich. The discrete spectrum is obtained and the wavefunction is expressed in terms of the Jacobi polynomial or the hypergeometric function. Some special cases of the Eckart potential are discussed for $D$=3, and the resulting energy equation agrees well with that obtained by other methods.
Maximum Momentum, Minimal Length and Quantum Gravity Effects of Compact Star Cores
Xiu-Ming Zhang, Wei Fu
Chin. Phys. Lett. 2016, 33 (01): 010401 .   DOI: 10.1088/0256-307X/33/1/010401
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Based on the generalized uncertainty principle with maximum momentum and minimal length, we discuss the equation of state of ideal ultra-relativistic Fermi gases at zero temperature. Maximum momentum avoids the problem that the Fermi degenerate pressure blows up since the increase of the Fermi energy is not limited. Applying this equation of state to the Tolman–Oppenheimer–Volkoff (TOV) equation, the quantum gravitational effects on the cores of compact stars are discussed. In the center of compact stars, we obtain the singularity-free solution of the metric component, $g_{\rm tt}\sim -(1+0.2185\times \tilde r^2)$. By numerically solving the TOV equation, we find that quantum gravity plays an important role in the region $r\sim 10^{4}\alpha_0(\Delta x)_{\min}$. Current observed masses of neutron stars indicate that the dimensionless parameter $\alpha_0$ cannot exceed $10^{19}$.
Optical Rogue Wave Excitation and Modulation on a Bright Soliton Background
Liang Duan, Zhan-Ying Yang, Chong Liu, Wen-Li Yang
Chin. Phys. Lett. 2016, 33 (01): 010501 .   DOI: 10.1088/0256-307X/33/1/010501
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We study rogue waves in an inhomogeneous nonlinear optical fiber with variable coefficients. An exact rogue wave solution that describes rogue wave excitation and modulation on a bright soliton pulse is obtained. Special properties of rogue waves on the bright soliton, such as the trajectory and spectrum, are analyzed in detail. In particular, our analytical results suggest a way of sustaining the peak shape of rogue waves on the soliton background by choosing an appropriate dispersion parameter.

NUCLEAR PHYSICS
Tilted Axis Rotation of $^{57}$Mn in Covariant Density Functional Theory
Jing Peng, Wen-Qiang Xu
Chin. Phys. Lett. 2016, 33 (01): 012101 .   DOI: 10.1088/0256-307X/33/1/012101
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The self-consistent tilted axis cranking covariant density functional theory based on the point-coupling interaction is applied to investigate the tilted axis rotation in $^{57}$Mn. The observed data for band C are reproduced well with the assigned configuration config 1. The shears mechanism for magnetic rotation is examined by investigating microscopically the orientation of angular momentum and the corresponding contributions. It is found that config 1 and config 3 correspond to a rotation of high-$K$ character. Config 2 corresponds to a rotation of magnetic character. However, due to the presence of electromagnetic transition $B(M1)$ and $ B(E2)$, collective rotation plays an essential role in the competition with magnetic rotation.

Effects of the HMT on Nucleon Collective Flows within BUU Transport Model
Fang Zhang
Chin. Phys. Lett. 2016, 33 (01): 012501 .   DOI: 10.1088/0256-307X/33/1/012501
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Within the framework of a semiclassical Boltzmann–Uehling–Uhlenbeck (BUU) transport model, the high momentum tail (HMT) effects of nucleon momentum distribution in the nucleus on the nucleon collective flows are studied in semicentral Au+Au collisions. The HMT due to the isospin-dependent short-range correlations causes a smaller value of the collective flows. We find that the HMT effects on the nucleon collective flows are remarkable at beam energy of 300 MeV/nucleon and become weak as the incident beam energy increases. The results indicate that for the collective flow studies at intermediate energies, the HMT of nucleon momentum distribution in nucleus should be taken into account in transport models.
Geometric Scaling Analysis of Deep Inelastic Scattering Data Including Heavy Quarks
Qing-Dong Wu, Ji Zeng, Yuan-Yuan Hu, Quan-Bo Li, Dai-Cui Zhou, Wen-Chang Xiang
Chin. Phys. Lett. 2016, 33 (01): 012502 .   DOI: 10.1088/0256-307X/33/1/012502
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An analytic massive total cross section of photon–proton scattering is derived, which has geometric scaling. A geometric scaling is used to perform a global analysis of the deep inelastic scattering data on inclusive structure function $F_2$ measured in lepton–hadron scattering experiments at small values of Bjorken $x$. It is shown that the descriptions of the inclusive structure function $F_2$ and longitudinal structure function $F_{\rm L}$ are improved with the massive analytic structure function, which may imply the gluon saturation effect dominating the parton evolution process at HERA. The inclusion of the heavy quarks prevent the divergence of the lepton–hadron cross section, which plays a significant role in the description of the photoproduction region.

ATOMIC AND MOLECULAR PHYSICS
Heating of Nanosized Liquid Water in High-Intensity Terahertz Pulses
Zi-Qian Huang, Rong-Yao Yang, Wei-Zhou Jiang, Qi-Lin Zhang
Chin. Phys. Lett. 2016, 33 (01): 013101 .   DOI: 10.1088/0256-307X/33/1/013101
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Non-equilibrium molecular dynamics simulations of liquid water in picosecond high-power terahertz pulses are performed by using a non-polarizable potential model. Numerical results show that the energy absorption of water molecules exhibits a pronounced resonance with THz pulses in the frequency range of 14–17 THz. With the THz pulse at resonant frequencies, the maximum temperature is about 562 K by heating the water at room temperature. Further investigation indicates that the results are independent of the size of the nanoscale water box. The efficiency of energy transfer by resonant absorption is more than seven times of microwave heating. These studies show promising applications of ultrashort THz pulses.

Orientation Dependence of Photoelectron Angular Distribution in Nitrogen Molecule Irradiated by XUV Laser Field
Xiao-Dong Yang, Ming Gao, Yuan Tian
Chin. Phys. Lett. 2016, 33 (01): 013102 .   DOI: 10.1088/0256-307X/33/1/013102
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We theoretically study the dependence of photoelectron angular distribution on laser polarization direction in nitrogen molecules. The approach is based on the time-dependent density functional theory at the level of local density approximation complemented by self-interaction correction. It is found that photoelectron emission in one photon regime could be considered as a probing tool for the main character of different types of molecular orbitals ($\sigma$ or $\pi$). The pattern of emitted photoelectrons strongly depends on the polarized angle of the laser, for $\sigma$ orbital, the number of photoelectron decreases with increasing the polarized angle, while for $\pi$ orbital, it has the inverse relation to the polarized angle, which reveals the multi-electron effect in molecules. On the other hand, concerning the total photoelectron emission, one should take into account a few occupied orbitals instead of only the outmost one.

FUNDAMENTAL AREAS OF PHENOMENOLOGY(INCLUDING APPLICATIONS)
Heat Transfer and Mode Transition for Laser Ablation Subjected to Supersonic Airflow
Yi-Hui Huang, Hong-Wei Song, Chen-Guang Huang
Chin. Phys. Lett. 2016, 33 (01): 014201 .   DOI: 10.1088/0256-307X/33/1/014201
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When laser ablation is subjected to supersonic flow, the influence mechanism of airflow on laser ablation behavior is still unclear. A coupled thermal-fluid-structure model is presented to investigate the influence of supersonic airflow on the development of a laser ablation pit. Results show that the aerodynamic convection cooling effect not only reduces the ablation velocity but also changes the symmetry morphology of the ablation pit due to the non-uniform convective heat transfer. Flow mode transition is also observed when the pit becomes deeper, and significant change in flow pattern and heat transfer behavior are found when the open mode is transformed into the closed mode.
Observation of Fano-Type Interference in a Coupled Cavity-Atom System
Yong Cheng, Zheng Tan, Jin Wang, Yi-Fu Zhu, Ming-Sheng Zhan
Chin. Phys. Lett. 2016, 33 (01): 014202 .   DOI: 10.1088/0256-307X/33/1/014202
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We present the experimental observation of the Fano-type interference in a coupled cavity-atom system by confining the laser-cooled $^{85}$Rb atoms in an optical cavity. The asymmetric Fano profile is obtained through quantum interference in a three-level atomic system coherently coupled to a single mode cavity field. The observed Fano profile can be explained by the interference between the intra-cavity dark state and the polariton state of the coupled cavity–atom system. The possible applications of our observations include all-optical switching, optical sensing and narrow band optical filters.

Diode-Pumped Passively Mode-Locked 1079nm Nd:CaGdAlO$_{4}$ Laser
Kun-Na He, Jia-Xing Liu, Long Wei, Xiao-Dong Xu, Zhao-Hua Wang, Wen-Long Tian, Zhi-Guo Zhang, Jun Xu, Ju-Qing Di, Chang-Tai Xia, Zhi-Yi Wei
Chin. Phys. Lett. 2016, 33 (01): 014203 .   DOI: 10.1088/0256-307X/33/1/014203
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We demonstrate a diode-pumped passively cw mode-locked Nd:CaGdAlO$_{4}$ laser operating at 1079 nm with a semiconductor saturable absorber mirror for the first time to the best of our knowledge. The threshold pump power of the laser is 180 mW. A maximum average output power of 93 mW is obtained under the pump power of 1.94 W. The pulse duration of the mode-locked pulses is 3.1 ps and the repetition rate is 157 MHz.

Controlling the Goos–Hänchen Shift via Incoherent Pumping Field and Electron Tunneling in the Triple Coupled InGaAs/GaAs Quantum Dots
R. Nasehi, S. H. Asadpour, H. Rahimpour Soleimani, M. Mahmoudi
Chin. Phys. Lett. 2016, 33 (01): 014204 .   DOI: 10.1088/0256-307X/33/1/014204
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We study the controlling of the Goos–Hänchen (GH) shifts in reflected and transmitted light beams in the triple coupled InGaAs/GaAs quantum dot (QD) nanostructures with electron tunneling and incoherent pumping field. It is shown that the lateral shift can become either large negative or large positive, which can be controlled by the electron tunneling and the rate of incoherent pump field in different incident angles. It is also demonstrated that the properties of the GH shifts are strongly dependent on the probe absorption beam of the intracavity medium due to the switching from superluminal light propagation to subluminal behavior or vice versa. Our suggested system can be considered as a new theoretical method for developing a new nano-optoelectronic sensor.

The Process of a Laser-Supported Combustion Wave Induced by Millisecond Pulsed Laser on Aluminum Alloy
Wei Zhang, Zhi Wei, Yi-Bin Wang, Guang-Yong Jin
Chin. Phys. Lett. 2016, 33 (01): 014205 .   DOI: 10.1088/0256-307X/33/1/014205
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We study the process of a laser-supported combustion wave (LSCW) when an aluminum alloy is irradiated by a millisecond pulse laser based on the method of laser shadowgraphy. Under the condition of different laser parameters, the obtained results include the velocity, ignition threshold of LSCW and the variation law. The speed of LSCW increases with the laser energy under the same irradiation laser pulse width, and the speed of LSCW reduces with the increase of the laser pulse width under the same irradiation laser energy. Moreover, the ignition time of LSCW becomes shorter by increasing the laser number of the pulse and is not effected by changing the frequencies, when keeping the laser pulse width and energy unchanged. The results of the study can be applied in the laser propulsion technology and metal surface laser heat treatment, etc.
Attack on Optical Double Random Phase Encryption Based on the Principle of Ptychographical Imaging
Tuo Li, Yi-Shi Shi
Chin. Phys. Lett. 2016, 33 (01): 014206 .   DOI: 10.1088/0256-307X/33/1/014206
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The principle of ptychography is applied in known plain text attack on the double random phase encoding (DRPE) system. We find that with several pairs of plain texts and cipher texts, the model of attack on DRPE can be converted to the model of ptychographical imaging. Owing to the inherent merits of the ptychographical imaging, the DRPE system can be breached totally in a fast and nearly perfect way, which is unavailable for currently existing attack methods. Further, since the decryption keys can be seen as an object to be imaged from the perspective of imaging, the ptychographical technique may be a kind of new direction to further analysis of the security of other encryption systems based on double random keys.

Simulation of High-Transmission Chiral Metamaterial with Impedance Matching to a Vacuum
Xiu-Li Jia, Qing-Xin Meng, Xiao-Ou Wang, Zhong-Xiang Zhou
Chin. Phys. Lett. 2016, 33 (01): 014207 .   DOI: 10.1088/0256-307X/33/1/014207
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For a previously simulated eight-broadband negative-refraction-index chiral metamaterial, we use S-parameter retrieval methods to determine the complex effective permittivity, permeability, and the impedance. We also calculate the figure of merit, which is defined as the ratio of the real and the imaginary refraction components, and compare it with those of fishnet metamaterials. The simulation results show that our chiral metamaterial exhibits high transmission and impedance matching to a vacuum. Also, we determine that the electric and magnetic dipoles of the surface plasmons play an important role in determining the nine resonance frequencies. Therefore, this investigation provides an experimental basis for developing metamaterial devices with multiple and broad resonance frequency bands.
Effects of Transverse Temperature Gradient on the Rotor Velocity in an Ultrasonic Motor
Li-Ping Cheng, Shu-Yi Zhang, Xiao-Dong Xu
Chin. Phys. Lett. 2016, 33 (01): 014301 .   DOI: 10.1088/0256-307X/33/1/014301
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As a result of the nonlinear effect, acoustic streaming has been widely used for increasing the transport coefficient or driving a rotor, for example, in resonant cavities and non-contact ultrasonic motors. It has been demonstrated by experiments that a temperature gradient transverse to the wave propagating direction can significantly increase the velocity of the streaming flows in resonant cavities. To check whether the transverse temperature gradient can also increase the working velocity of acoustic streaming-driven motors, we investigate this issue by numerically solving the hydrodynamic equations. It is found that the velocity of the rotor only weakly depends on the transverse temperature gradient, e.g., even with a temperature difference of 40$^{\circ}\!$C between the rotor and the stator, the velocity increases only $\sim$8.8%.
Three-Dimensional Scattering of an Incident Plane Shear Horizontal Guided Wave by a Partly through-Thickness Hole in a Plate
Wen-Fa Zhu, Hai-Yan Zhang, Jian Xu, Xiao-Dong Chai
Chin. Phys. Lett. 2016, 33 (01): 014302 .   DOI: 10.1088/0256-307X/33/1/014302
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We investigate the three-dimensional (3D) scattering problem of an incident plane shear horizontal wave by a partly through-thickness hole in an isotropic plate, in which the Lamb wave modes are also included due to the mode conversions by the scattering obstacle in the 3D problem. An analytical model is presented such that the wave fields are expanded in all of propagating and evanescent SH modes and Lamb modes, and the scattered far-fields of three fundamental guided wave modes are analyzed numerically for different sizes of the holes and frequencies. The numerical results are verified by comparing with those obtained by using the approximate Poisson/Mindlin plate model for small hole radius and low frequency. It is also found that the scattering patterns are different from those of the S0 wave incidence. Our work is useful for quantitative evaluation of the plate-like structure by ultrasonic guided waves.

PHYSICS OF GASES, PLASMAS, AND ELECTRIC DISCHARGES
Modulation of Void Motion Behavior in a Magnetized Dusty Plasma
Zi-Juan Xie, Yu Sui, Yi Wang, Xian-Jie Wang, Yang Wang, Zhi-Guo Liu, Bing-Sheng Li, Yu Bai, Zhi-Hao Wang
Chin. Phys. Lett. 2016, 33 (01): 015201 .   DOI: 10.1088/0256-307X/33/1/015201
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Based on fluid equations, we show a time-dependent self-consistent nonlinear model for void formation in magnetized dusty plasmas. The cylindrical configuration is applied to better illustrate the effects of the static magnetic field, considering the azimuthal motion of the dusts. The nonlinear evolution of the dust void and the rotation of the dust particles are then investigated numerically. The results show that, similar to the unmagnetized one-dimensional model, the radial ion drag plays a crucial role in the evolution of the void. Moreover, the dust rotation is driven by the azimuthal ion drag force exerting on the dust. As the azimuthal component of ion velocity increases linearly with the strength of the magnetic field, the azimuthal component of dust velocity increases synchronously. Moreover, the angular velocity gradients of the dust rotation show a sheared dust flow around the void.

Theoretical Analysis of the Frequency Jump in E-fishbone Experiments
Yi-Fan Yan, Zhong-Tian Wang, Zhi-Xiong He, Li-Ming Yu, Zhan-Hui Wang, Jia-Qi Dong, Hui-Dong Li, Hao Feng
Chin. Phys. Lett. 2016, 33 (01): 015202 .   DOI: 10.1088/0256-307X/33/1/015202
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It is identified that barely passing electrons are the drive of the e-fishbones, rather than the barely trapped electrons at low frequency. The frequency jump in e-fishbone experiments is reproduced and analyzed. It is found that the e-fishbone frequency increases with the hot electron energy, which is consistent with the experiments. The growth rate of the mode ($m=2$, $n=2$) is greater than that of the mode ($m=1$, $n=1$).

Bias Effects on the Reynolds Stress Using the Multi-Purpose Probe in IR-T1 Tokamak
M. Lafouti, M. Ghoranneviss
Chin. Phys. Lett. 2016, 33 (01): 015203 .   DOI: 10.1088/0256-307X/33/1/015203
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The effect of the positive bias on Reynolds stress (RS) and its effect on the radial turbulent transport at the edge plasma ($r/a=0.9$) and scrape-off layer (SOL) region of plasma in tokamak are investigated. The radial and poloidal electric fields ($E_{\rm r}$, $E_{\rm p}$) and ion saturation current ($I_{\rm s}$) are measured by multi-purpose probe (MPP). This probe is fabricated and constructed for the first time in the IR-T1 tokamak. The most advantage of this probe is that the variations of $E_{\rm r}$ and $E_{\rm p}$ can be measured in different radii at the single shot. Thus the information of different radii can be compared with high precision. The bias voltage is fixed at $V_{\rm bias}=200$ V and it has been applied with the limiter bias that is fixed in $r/a=0.9$. Moreover, the phase difference between radial and poloidal electric fields, and temporal evolution of the RS spectrum detected by MPP are calculated. RS magnitude on the edge ($r/a=0.9$) is more than its value in the SOL ($r/a=1.02$). With the applied bias 200 V, RS and the magnitude of the phase difference between $E_{\rm r}$ and $E_{\rm p} $ are increased, while the radial turbulent transport is decreased simultaneously. Thus it can be concluded that RS affects radial turbulence. Temporal evolution of the RS spectrum shows that the frequency of RS is increased and reaches its highest value at $r/a$=0.9 in the presence of bias.

CONDENSED MATTER: STRUCTURE, MECHANICAL AND THERMAL PROPERTIES
Impact of Native Defects in the High Dielectric Constant Oxide HfSiO$_{4}$ on MOS Device Performance
Hai-Kuan Dong, Li-Bin Shi
Chin. Phys. Lett. 2016, 33 (01): 016101 .   DOI: 10.1088/0256-307X/33/1/016101
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Native defects in HfSiO$_{4}$ are investigated by first principles calculations. Transition levels of native defects can be accurately described by employing the nonlocal HSE06 hybrid functional. This methodology overcomes the band gap problem in traditional functionals. By band alignments among the Si, GaAs and HfSiO$_{4}$, we are able to determine the position of defect levels in Si and GaAs relative to the HfSiO$_{4}$ band gap. We evaluate the possibility of these defects acting as fixed charge. Native defects lead to the change of valence and conduction band offsets. Gate leakage current is evaluated by the band offset. In addition, we also investigate diffusions of native defects, and discuss how they affect the MOS device performance.
Effect of Al Addition on the Glass-Forming Ability and Magnetic Properties of a Gd–Co Binary Amorphous Alloy
Cheng Wu, Ding Ding, Lei Xia
Chin. Phys. Lett. 2016, 33 (01): 016102 .   DOI: 10.1088/0256-307X/33/1/016102
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The glass-forming ability (GFA) and magnetic properties of the Gd$_{50}$Co$_{50}$-based amorphous alloy with Al addition substitution for Co are investigated. It is found that the GFA and magneto-caloric effect of the Gd$_{50}$Co$_{45}$Al$_{5}$ amorphous alloy are better than Gd$_{50}$Co$_{50}$ amorphous alloy. The maximum magnetic entropy change ($-\Delta S_{\rm m}^{\rm peak})$ and the magnetic refrigerant capacity of the amorphous alloy under a field of 5 T are about 6.64 J$\cdot$kg$^{-1}$K$^{-1}$ and 764 J$\cdot$kg$^{-1}$, respectively. The field dependence of magnetic entropy change meets the one predicted by the mean field theory, which is investigated for a better understanding of the magneto-caloric behaviors of the Gd$_{50}$Co$_{45}$Al$_{5}$ amorphous alloy.
Influence of UV-Irradiation on Latent Tracks in Polyethylene Terephthalate Films
Qi Wen, Peng-Fei Wang, Yun Ling, Mao Wang, Dong-Xiao Yan, Xing-Zhong Cao, Bao-Yi Wang, Yu-Gang Wang
Chin. Phys. Lett. 2016, 33 (01): 016103 .   DOI: 10.1088/0256-307X/33/1/016103
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Polyethylene terephthalate (PET) films in thickness of 12 $\mu$m are irradiated by Xe and Au ions at the energies of 9.5 and 11.4 MeV/u and with the ion fluence from $5\times10^{9}$ cm$^{-2}$ to $1\times10^{11}$ cm$^{-2}$. After irradiation, ultra-violet lights are used to illuminate the samples with latent tracks at the wavelength of 365 nm with flux density of 4.2 mW/cm$^{-2}$. UV-irradiation effects on tracked PET are investigated by the UV-vis spectrum and positron annihilation lifetime spectroscopy (PALS). It is found that carbonaceous clusters in PET films are generated by ion irradiation and decomposed with UV illumination by calculating the optical energy band gap $E_{\rm g}$ in the UV-vis spectrum. The free volumes behave differently in track and bulk after UV illumination. In our experiment, the PALS results show an increase in radius and density of free volume in tracked PET films after UV treatment, which indicates an expansion in radius of latent tracks.

Sc-Decorated WS$_{2}$ Nanoribbons as Hydrogen Storage Media
Bin Xu, Yu-Sheng Wang, Na-Hong Song, Jing Zhang, Meng Li, Lin Yi
Chin. Phys. Lett. 2016, 33 (01): 016802 .   DOI: 10.1088/0256-307X/33/1/016802
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The hydrogen storage behavior of Sc-decorated WS$_{2}$ monolayer and WS$_{2}$ nanoribbons is systematically studied by using first principles calculations based on the density functional theory. The present results indicate that an Sc-decorated WS$_{2}$ monolayer is not suitable for storing hydrogen due to the weak interaction between the monolayer WS$_{2}$ sheet and the Sc atoms. It is found that both the hybridization mechanism and the Coulomb attraction make the Sc atoms stably adsorb on the edges of WS$_{2}$ nanoribbons without clustering. The 2Sc/WS$_{2}$NRs system can adsorb at most eight H$_{2}$ molecules with average adsorption energy of 0.20 eV/H$_{2}$. The results show that the desorption of H$_{2}$ is possible by lowering the pressure or by increasing the temperature.

CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES
Influence of the Magnetic Moment on the Atomic Distance in Amorphous Ce$_{x}$Ru$_{100-x}$
Ying-Jie Li, Ikuo Nakai, Yusuke Amakai, Shigeyuki Murayama
Chin. Phys. Lett. 2016, 33 (01): 017101 .   DOI: 10.1088/0256-307X/33/1/017101
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We perform the extended x-ray absorption fine structure (EXAFS) measurement to investigate the local structure of amorphous alloys Ce$_{x}$Ru$_{100-x}$ ($x=9$, 43 and 80). The interatomic distances of the nearest Ru–Ce and Ru–Ru pairs derived from EXAFS are fully independent of Ce concentration. On the other hand the distance between neighboring Ce atoms increases sharply with the Ce content, which is exactly proportional to the Ce effective magnetic moment. We discuss the relation between the atomic distance and the effective magnetic moment from the point of view of the magneto-volume effect.

Effect of Residual Charge Carrier on the Performance of a Graphene Field Effect Transistor
Sedighe Salimian, Mohammad Esmaeil Azim Araghi
Chin. Phys. Lett. 2016, 33 (01): 017201 .   DOI: 10.1088/0256-307X/33/1/017201
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The temperature-dependent effect of residual charge carrier ($n_{0})$, at the Dirac point, on mobility is studied. We fabricate and characterize a graphene field effect transistor (GFET) using 7 nm TiO$_{2}$ as the top-gate dielectric. The temperature-dependent gate voltage-drain current and room temperature gate capacitance are measured to extract the carrier mobility and to estimate the quantum capacitance of the GFET. The device shows the mobility value of 900 cm$^{2}$/V$\cdot$s at room temperature and it decreases to 45 cm$^{2}$/V$\cdot$s for 20 K due to the increase of $n_{0}$. These results indicate that the phonon scattering is not the dominant process for the unevenness dielectric layer while the coulomb scattering by charged impurities degrades the device characteristically at low temperature.
Anomalous Direct-Current Josephson Effect in Semiconductor Nanowire Junctions$^{*}$
Bin-He Wu, Xu-Yu Feng, Chao Wang, Xiao-Feng Xu, Chun-Rui Wang
Chin. Phys. Lett. 2016, 33 (01): 017401 .   DOI: 10.1088/0256-307X/33/1/017401
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We investigate the dc Josephson effect in one-dimensional junctions where a ring conductor is sandwiched between two semiconductor nanowires with proximity-induced superconductivity. Peculiar features of the Josephson effect arise due to the interplay of spin-orbit interaction and external Zeeman field. By tuning the Zeeman field orientation, the device can vary from 0 to $\pi$ junction. More importantly, nonzero Josephson current is possible at zero phase difference across the junction. Although this anomalous Josephson current is not relevant to the topological phase transition, its magnitude can be significantly enhanced when the nanowires become topological superconductors where Majorana bound states emerge. Distinct modulation patterns are obtained for the semiconductor nanowires in the topologically trivial and non-trivial phases. These results are useful to probe the topological phase transition in semiconductor nanowire junctions via the dc Josephson effect.
Detection of DNA Bases Using Fe Atoms and Graphene
Jian-Fen Hu, Lin Feng, Wen-Xing Zhang, Yong Li, Ya-Xin Lu
Chin. Phys. Lett. 2016, 33 (01): 017901 .   DOI: 10.1088/0256-307X/33/1/017901
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The adsorption of DNA bases on a magnetic probe composed of Fe atoms and graphene is studied by using first-principles calculations. The stability of geometry, the electronic structure and magnetic property are investigated. The results indicate that four DNA bases, i.e., adenine, thymine, cytosine and guanine, can all be adsorbed on the probe solidly. However, the magnetic moments of the composite structure can be observed only when adenine adsorbs on the probe. In the cases of the adsorption of the other three bases, the magnetic moments of the composite structure are zero. Based on the significant change of magnetic moment of the composite structure, adenine can be distinguished conveniently from thymine, cytosine and guanine. This work may provide a new way to detect DNA bases.

CROSS-DISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY
Determination of Traps' Density of State in OLEDs from Current–Voltage Analysis
M. S. Zaini, M. A. Mohd Sarjidan, W. H. Abd. Majid
Chin. Phys. Lett. 2016, 33 (01): 018101 .   DOI: 10.1088/0256-307X/33/1/018101
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A simple method to determine the traps' density of state (DOS) in organic light-emitting diodes (OLEDs) by manipulating the current–voltage ($I$–$V$) characteristic of the devices at room temperature is introduced. In particular, the trap-dependent space-charge limited current formula is simplified to obtain effective density of traps. In this study, poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3] thiadiazol-4,8-diyl)] (F8BT) and 2-Methoxy-5-(3$'$,7$'$-dimethyloctyloxy) benzene-1,4-diacetonitrile (OC$_{1}$C$_{10}$-PPV) are selected as the OLEDs emissive layer. The trap DOS of F8BT- and OC$_{1}$C$_{10}$-PPV-based OLEDs are calculated in the magnitudes of 10$^{24}$ m$^{-3}$ and 10$^{23}$ m$^{-3}$, respectively. In addition, the results agree with the other conventional method which is used to determine the trap DOS in OLEDs. This calculation technique may serve as a robust and reliable approach to obtain the trap DOS in OLEDs at room temperature.

A Comparative Study of Dispersion Characteristics Determination of a Trapezoidally Corrugated Slow Wave Structure Using Different Techniques
Md. Ghulam Saber, Rakibul Hasan Sagor, Md. Ruhul Amin
Chin. Phys. Lett. 2016, 33 (01): 018401 .   DOI: 10.1088/0256-307X/33/1/018401
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The linear dispersion relation of a trapezoidally corrugated slow wave structure (TCSWS) is analyzed and presented. The size parameters of the TCSWS are chosen in such a way that they operate in the x-band frequency range. The dispersion relation is solved by utilizing the Rayleigh–Fourier method by expressing the radial function in terms of the Fourier series. A highly accurate synthetic technique is also applied to determine the complete dispersion characteristics from experimentally measured resonances (cold test). Periodic structures resonate at specific frequencies when the terminals are shorted appropriately. The dispersion characteristics obtained from numerical calculation, synthetic technique and cold test are compared, and an excellent agreement is achieved.
Efficient Solution to Electromagnetic Scattering Problems of Bodies of Revolution by Compressive Sensing
Meng Kong, Ming-Sheng Chen, Liang Zhang, Xin-Yuan Cao, Xian-Liang Wu
Chin. Phys. Lett. 2016, 33 (01): 018402 .   DOI: 10.1088/0256-307X/33/1/018402
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Under the theory structure of compressive sensing (CS), an underdetermined equation is deduced for describing the discrete solution of the electromagnetic integral equation of body of revolution (BOR), which will result in a small-scale impedance matrix. In the new linear equation system, the small-scale impedance matrix can be regarded as the measurement matrix in CS, while the excited vector is the measurement of unknown currents. Instead of solving dense full rank matrix equations by the iterative method, with suitable sparse representation, for unknown currents on the surface of BOR, the entire current can be accurately obtained by reconstructed algorithms in CS for small-scale undetermined equations. Numerical results show that the proposed method can greatly improve the computational efficiency and can decrease memory consumed.

Interaction of Pair Particles Mediated by Signal Molecules
Jiang-Xing Chen, Qiang Zheng, Chun-Yun Huang, Jiang-Rong Xu, He-Ping Ying
Chin. Phys. Lett. 2016, 33 (01): 018701 .   DOI: 10.1088/0256-307X/33/1/018701
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A mesoscopic model is set up to study the predator–prey-like phenomenon between two chemically active objects. A target sphere (T) secretes chemical signal molecules that are detected and traced by a hunter sphere (H). The distribution of signal molecules diffusing around the target is simulated and analyzed. The chemotactic behavior of the hunter along the gradient of signal molecules results in the capture of the target. The dependences of capture time $t_{\rm c}$ on different conditions are focused on. It is found that the values of capture time rely on their initial separation $d$ as a power law $t_{\rm c}\propto d^{\alpha}$. The exponent $\alpha$ depends on decay rate of signal molecules. The capture time increases with the decay rate. The increases of target and hunter size both lead to the decrease of the capture time, which is also shown by the power law behavior. The detailed chemotaxis process is investigated.

Nanomechanical Properties of Amyloid Fibrils Formed in a Water Nanofilm on Mica Surface
Lan-Jie Wang, Li-Xia Kong, Lan-Lan Su, Zi-Qi Zhao, Gong-Jun Zhang, Xing-Fei Zhou
Chin. Phys. Lett. 2016, 33 (01): 018702 .   DOI: 10.1088/0256-307X/33/1/018702
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The assessment of nanomechanical properties of a single amyloid fibril in a confined space provides important information for understanding the role of fibrils in a cell microenvironment. In this study, the structure and nanomechanical properties of different fibrils formed in water nanofilms on mica surface are carefully investigated by using the new atomic force microscopy imaging mode-peak force quantitative nanomechanics (PF-QNM). We find that two types of fibrils with different morphologies are formed in water nanofilm on mica. The compression elasticities of these two types of fibrils are 3.9$\pm$0.9 and 2.5$\pm$0.6 GPa, respectively. The remarkable difference is possibly due to the structural discrepancy in two types of fibrils.

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