Modern Physics Letters B

As CMOS technology extends beyond the current technology node, many challenges to conventional MOSFET were raised. Non-classical CMOS to extend and fundamentally new technologies to replace current CMOS technology are under intensive investigation to meet these challenges. The approach of hybrid silicon/molecular electronics is to provide a smooth transition technology by integrating molecular intrinsic scalability and diverse properties with the vast infrastructure of traditional MOS technology. Here we discuss: (1) the integration of redox-active molecules into Si-based structures, (2) characterization and modeling of the properties of these Si/molecular systems, (3) single and multiple states of Si/molecular memory, and (4) applications based on hybrid Si/molecular electronic system.

The Kolmogorov complexity of a physical state is the minimal physical resources required to reproduce that state. We define a second quantized quantum Turing machine and use it to define second quantized Kolmogorov complexity. There are two advantages to our approach — our measure of the second quantized Kolmogorov complexity is closer to physical reality and unlike other quantum Kolmogorov complexities, it is continuous. We give examples where the second quantized and quantum Kolmogorov complexity differ.

In this paper, the microstructure of porous silicon was discussed by scanning electron microscopy and Raman spectra. The compositions of the samples were studied by X-ray diffraction and electron diffraction. The luminescent properties of porous silicon were explored by the PL measurements. The results showed that the structure of the top porous silicon prepared by epitaxial silicon consists of meso-pores and that of the underlying porous silicon consists of macro-pores. Furthermore, the structure of porous silicon prepared by heavily doped silicon is made of nano-pores. The composition of porous silicon consists of the single-crystal phase, poly-crystal phase and amorphous-crystal phase, respectively. In addition, the luminescence of porous silicon may come from the defects on the silicon-rod surface and in Si complexes including siloxene, Si oxide and Si hydrides, and may not be related to amorphous phase and nano-phase.

Based on the pseudopotential scheme under the virtual crystal approximation that takes into account the effect of compositional disorder combined with the bond-orbital model of Harrison, the results of calculations of elastic constants and surface and bulk acoustic wave speeds of Cd_1-xZn_xTe mixed crystals in the zinc-blende structure are presented. The agreement between our results and known data, which are only available for CdTe and ZnTe is found to be reasonable.

We obtain the exact solutions of a single particle magneto-confined in a one-dimensional (1D) quantum wire with a single square barrier. Theoretical analysis and numerical computation show that for a set of fixed barrier height and width, the quantum levels and states of the system depend on the displacement d of the magnetic trap, and for a fixed d value the system occupies only one or two lower quantum levels of n ≤ 20 of a free harmonic oscillator. In the barrier region, the finite-sized effect implies that only for some discrete barrier parameters and d values, the system has the Hermitian polynomial solutions, otherwise it has the infinite series solutions. Therefore, one can manipulate the external motional states of the system and prepare some required lower energy states by adjusting the displacement of the magnetic trap experimentally.

In this letter, a efficient scheme is proposed for the quantum secret encryption and decryption implementation for quantum secret sharing protocol with trapped ions in thermal motion, in which the effective Hamiltonian does not involve the external degree of freedom and thus the scheme is insensitive to the external state, allowing it to be thermal state. The proposed scheme requires no auxiliary states to assist intermediate atomic transitions and conditional quantum dynamics for quantum phase flip and quantum state diffusion. Besides, secret transmission using entanglement swapping also has been presented.

Polycrystalline Dy-modified Pb_1-xK_2xNb₂O₆ (PKN) ferroelectric ceramic with a general formula Pb_1-xK_2x-3yM_yNb₂O₆ for x=0.20, y=0.10 and M=Dy, have been prepared by the solid-state reaction route. The X-ray diffraction (XRD) studies of the material at room temperature revealed orthorhombic structure with lattice parameters a=17.701 Å, b=17.958 Å and c=3.883 Å. The dielectric anomaly with a sharp peak is observed at 430°C. The impedance plots are used as a tool to analyze the sample behavior as a function of frequency. The grain and grain boundary contributions are estimated. The modulus mechanism indicates the non-Debye type relaxation. The activation energy value near the phase transition temperature has been found to be different in the above T_C from AC conductivity measurements.

Zinc manganese phosphate glasses (ZnO-MnO-P₂O₅) of different compositions are synthesized. The optical band gaps are measured in the UV-VIS region. Photoconduction measurements are also made in the spectral energy range 1.5–6.2 eV. At various applied electric fields, the values of the energy band gaps have been deduced from the spectral dependence curves. Furthermore, the band gaps at zero applied voltage were also obtained for different compositions. The charge transport mechanism in these glasses is studied under the Mott's model.