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Koshino K.,Tokyo Medical and Dental University | Nakamura Y.,NEC Corp | Nakamura Y.,RIKEN | Nakamura Y.,Research Center for Advanced Science and Technology
New Journal of Physics | Year: 2012

We investigate the dynamics of a superconducting qubit strongly coupled to a semi-infinite one-dimensional microwave field having a variable boundary condition. The radiative level shift and linewidth of the qubit are controllable through the boundary condition of the field, and the spectral properties of the output microwave are modified accordingly. The current scheme provides a compact method for controlling the radiative characteristics of quantum few-level systems that is useful in single-photon engineering. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft. Source

Aiba Y.,Research Center for Advanced Science and Technology
Artificial DNA, PNA & XNA | Year: 2012

Peptide nucleic acid (PNA) is one of the most widely used synthetic DNA analogs. Conjugation of functional molecules to PNA is very effective to further widen its potential applications. For this purpose, here we report the synthesis of several ligand monomers and introduced them to PNA. These ligand-modified PNAs attract cerium ion and are useful for site-selective DNA hydrolysis. It should be noted that these ligands on PNA are also effective even under the conditions of invasion complex. Source

Yoshigoe H.,University of Tokyo | Kadoya S.,University of Tokyo | Takahashi S.,University of Tokyo | Takahashi S.,Research Center for Advanced Science and Technology | Takamasu K.,University of Tokyo
International Journal of Automation Technology | Year: 2014

Recently, three-dimensional microstructures have been attracting much attention because of their potential application to electromagnetic devices operating with specific frequencies such as THz wave. For suitability in such applications, the structures often need to have complex three-dimensional shapes, be smaller than or at least as small as the applied wavelengths, consist of metals or dielectric materials, and have certain electromagnetic characteristics such as high permittivity. Although there are several methods for fabricating micro-structures, few of them satisfy all of these conditions. We propose a new fabrication method for dielectric-metal three-dimensional structures with sizes of a few tens of micrometers. The main feature of our method is the extraction of metal using photocatalyst nanoparticles. Silver ions in solution are reduced to neutral silver by electrons from the photocatalyst nanoparticles. Experimental results show that our system can be used to fabricate threedimensional structures, and we propose a new method for controlling the composition of the structures. Source

News Article
Site: http://phys.org/physics-news/

A research group at Osaka University has succeeded in observing at the intended timing two-phonon quantum interference by using two cold calcium ions in ion traps, which spatially confine charged particles. A phonon is a unit of vibrational energy that arises from oscillating particles within crystals. Two-particle quantum interference experiments using two photons or atoms have been previously reported, but this group's achievement is the world's first observation using two phonons. This group demonstrated that the phonon, a quantum mechanical description of an elementary vibrational motion in matter, and the photon, an elementary particle of light, share common properties. This group's research results will contribute to quantum information processing research, including quantum simulation using phonons and quantum interface research. Ion traps are an important technique in physically achieving quantum information processing including quantum computation, and research on ion traps is being carried out all over the world, with Dr. David J. Wineland of the United States, a leading expert in the field, winning the Nobel Prize in Physics in 2012. For this research, a team from Osaka University led by Shinji Urabe, Professor Emeritus, Kenji Toyoda, Assistant Professor, and Atsushi Noguchi (currently at the Research Center for Advanced Science and Technology, The University of Tokyo) used a laser to irradiate 2 calcium ions to completely remove almost any movement energy from the ions. After this, the team caused a single phonon to form at each of the ion sites. Since there is mutual interaction between the two ions, this causes the phonons to move and mutually interfere with each other. In the case of classical particles, there is a possibility that the particles will be detected individually at each of the sites. However, with phonons, since the effects of two-phonon interference eliminate the possibility of each particle being detected individually, it was predicted that the two phonons would be detected simultaneously at one of the two ion sites. Through experimentation, the two phonons were in fact detected at the same site, confirming that the probability of simultaneous detection of the phonons at individual ion sites is close to zero. This phenomenon is a distinctive interference effect in bosonic particles such as photons, elementary particles of light, and phonons, the quantum of vibrational energy; a typical phenomenon which indicates quantum characteristics. Since this phenomenon can only be observed when the quantum particles have been properly prepared simultaneously, the success rate when performed with photons is limited. However, with ion traps, individual phonons can be created with a high level of control, allowing for successful observation at specific timing on demand. Explore further: Quantum information motion control is now improved

Ohshima Y.,Research Center for Advanced Science and Technology | Noguchi Y.,Research Center for Advanced Science and Technology | Oguchi T.,Research Center for Advanced Science and Technology | Kitanaka Y.,Research Center for Advanced Science and Technology | And 3 more authors.
ECS Transactions | Year: 2012

Perovskite oxides solid solutions of ferroelectric Bi 0.5Na 0.5TiO 3 and paraelectric Ba(Mg 1/3Nb 2/3)O 3, namely (1-x)Bi 0.5Na 0.5TiO 3-xBa(Mg 1/3Nb 2/3)O 3 [(1-x)BNT-xBMN], were synthesized and their crystal structures were analyzed by high-resolution neutron powder diffraction Rietveld analysis. Structural analysis shows that (1-x)BNT-xBMN constitutes two-phase mixture region composed of rhombohedral R3c and cubic Pm 3 m in its phase diagram. Measurements of dielectric, ferroelectric polarization, and electric-field- induced strain properties indicate that (1-x)BNT-xBMN exhibits ferroelectric and piezoelectric properties for x < 0.04 while paraelectric properties for x > 0.05. Dielectric permittivity of (1-x)BNT-xBMN ceramics with x = 0.05 was an extremely high value of 2000-3000 in the high temperature range of 200-400°C. ©The Electrochemical Society. Source

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