Author Takasugi, Shota| Watanabe, Keita| Misawa, Masaaki| Tsuruta, Kenji|
Note This fulltext is available in Feb. 2022.|
Published Date 2021-02-22
Publication Title Japanese Journal of Applied Physics
Volume volume60
Issue issueSD
Publisher IOP Publishing
Start Page SDDA01
ISSN 0021-4922
NCID AA12295836
Content Type Journal Article
language 英語
OAI-PMH Set 岡山大学
File Version author
DOI 10.35848/1347-4065/abe2e5
Web of Science KeyUT 000621475200001
Related Url isVersionof https://doi.org/10.35848/1347-4065/abe2e5
Author Iida, Takumi | Ishikawa, Atsushi| Tanaka, Takuo| Muranaka, Atsuya| Uchiyama, Masanobu| Hayashi, Yasuhiko| Tsuruta, Kenji|
Note This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Takumi Iida et. al. Super-chiral vibrational spectroscopy with metasurfaces for high-sensitive identification of alanine enantiomers. Appl. Phys. Lett. 117, 101103 (2020) and may be found at https://doi.org/10.1063/5.0012331. </br>This fulltext is available in Sep. 2021.|
Published Date 2020-09-09
Publication Title Applied Physics Letters
Volume volume117
Issue issue10
Publisher American Institute of Physics
Start Page 101103
ISSN 0003-6951
NCID AA00543431
Content Type Journal Article
language 英語
OAI-PMH Set 岡山大学
File Version publisher
DOI 10.1063/5.0012331
Web of Science KeyUT 000571581400002
Related Url isVersionOf https://doi.org/10.1063/5.0012331
FullText URL fulltext.pdf
Author Suichi, Takahiro| Ishikawa, Atsushi| Tanaka, Takuo| Hayashi, Yasuhiko| Tsuruta, Kenji|
Published Date 2020-04-16
Publication Title Scientific Reports
Volume volume10
Issue issue1
Publisher Nature
Start Page 6486
ISSN 2045-2322
Content Type Journal Article
language 英語
OAI-PMH Set 岡山大学
Copyright Holders © The Author(s) 2020
File Version publisher
PubMed ID 32300158
DOI 10.1038/s41598-020-63591-7
Web of Science KeyUT 000562142100005
Related Url isVersionOf https://doi.org/10.1038/s41598-020-63591-7
FullText URL JJAP_59.pdf
Author Watanabe, Keita| Fujita, Mikiya| Tsuruta, Kenji|
Note This fulltext is available in Apr. 2021.|
Published Date 2020-04-06
Publication Title Japanese Journal of Applied Physics
Volume volume59
Issue issueSK
Publisher Japan Society of Applied Physics
Start Page SKKA06
ISSN 0021-4922
NCID AA12295836
Content Type Journal Article
language 英語
OAI-PMH Set 岡山大学
Copyright Holders © 2020 The Japan Society of Applied Physics
File Version author
DOI 10.35848/1347-4065/ab7e3e
Web of Science KeyUT 000546613200005
Official Url https://iopscience.iop.org/article/10.35848/1347-4065/ab7e3e|
FullText URL fulltext.pdf
Author Hada, Masaki| Yamaguchi, Daisuke| Ishikawa, Tadahiko| Sawa, Takayoshi| Tsuruta, Kenji| Ishikawa, Ken| Koshihara, Shin-Ya| Hayashi, Yasuhiko| Kato, Takashi|
Published Date 2019-09-13
Publication Title Nature Communications
Volume volume10
Publisher Nature Publishing Group
Start Page 4159
ISSN 2041-1723
Content Type Journal Article
language 英語
OAI-PMH Set 岡山大学
Copyright Holders © The Author(s) 2019
File Version publisher
PubMed ID 31519876
DOI 10.1038/s41467-019-12116-6
Web of Science KeyUT 000485685200005
Related Url isVersionOf https://doi.org/10.1038/s41467-019-12116-6
JaLCDOI 10.18926/19953
FullText URL Mem_Fac_Eng_OU_44_1.pdf
Author Nagai Shinji| Umeda Ryosuke| Tsuruta, Kenji|
Abstract In this paper, we investigate a light-confinement phenomenon in the structure which has triangular latice composed of Double NeGative Metamaterial (DNGM). In geometrical optics consideration, this structure is expected to confine lights completely by sequential refractions in the structure. We demonstrate it by using the two dimensional finite-difference time-domain simulations. We introduce Drude-Lorentz model for dielectric and magnetic dispersion of the material at optical frequencies. We analyze quantitatively the effects of energy loss in the DNGM on the light-confinement efficiency.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2010-01
Volume volume44
Start Page 1
End Page 6
ISSN 1349-6115
language 英語
File Version publisher
NAID 120002309117
JaLCDOI 10.18926/19954
FullText URL Mem_Fac_Eng_OU_44_7.pdf
Author Maetani Noriaki| Kurose Tomoyuki| Tsuruta, Kenji|
Abstract The lens effect of acoustic waves in a two-dimensional (2D) phononic crystal is studied by numerical simulation based on the finite-difference time-domain (FDTD) method. We calculate the phonon band structure of 2D phononic crystals, consisting of metal cylinders placed periodically in water. Lens effect is observed by the negative refraction of acoustic waves, which results in refocusing of the waves at the point outside the crystal. To increase the focal intensity, we introduce a 2D phononic crystal shield with a different composition of material, which returns the incident waves back to the lens via the perfect reflection. Also, the dependence on filling fraction of metal in the crystal is studied.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2010-01
Volume volume44
Start Page 7
End Page 12
ISSN 1349-6115
language 英語
File Version publisher
NAID 120002309019
JaLCDOI 10.18926/17829
FullText URL Mem_Fac_Eng_OU_43_16.pdf
Author Kurose Tomoyuki| Tsuruta, Kenji| Totsuji, Chieko| Totsuji, Hiroo|
Abstract The finite-difference time-domain (FDTD) method has been applied to the calculation of the phonon band structure of two-dimensional (2D) phononic crystals, consisting of metal cylinders placed periodically in liquid. By comparing several combinations of materials for metal cylinder and liquid, we analyze the dependence of the band structures on sound speed and density of liquid media. Moreover, the negative refraction of the acoustic waves is observed at the interfaces between phononic crystal slab and the liquid. We find that an acoustic“lens effect”with the slab appears due to the negative refractions. The relationship between the focal intensity in the lens effect and the band structure is discussed.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2009-01
Volume volume43
Start Page 16
End Page 21
ISSN 1349-6115
language 英語
File Version publisher
NAID 120002308928
JaLCDOI 10.18926/17831
FullText URL Mem_Fac_Eng_OU_43_22.pdf
Author Totsuji, Hiroo| Chai Hong| Totsuji, Chieko| Tsuruta, Kenji|
Abstract For the transfer of quantum information and the creation of entangled states, the application of tuned spin chains, systems of spins with the nearest-neighbor coupling tuned so as to give high efficiency, has been proposed and some examples of high performance have been given by several authors. In this article, the effect of deviations from tuned values and the effect of resultant asymmetry are investigated through numerical simulations and theoretical analyses. It is shown that there exists a system where the transfer efficiency is comparable with exactly tuned ones and, at the same time, robust to noises in the coupling constants. It is also shown that the effect of asymmetry on the efficiency of entanglement creation is of the second order when the asymmetry is small.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2009-01
Volume volume43
Start Page 22
End Page 26
ISSN 1349-6115
language 英語
File Version publisher
NAID 120002308966
JaLCDOI 10.18926/17826
FullText URL Mem_Fac_Eng_OU_43_8.pdf
Author Umeda Ryosuke| Totsuji, Chieko| Tsuruta, Kenji| Totsuji, Hiroo|
Abstract Metamaterial which has negative permittivity and permeability is investigated via computer simulations. Effects of the nanostructure on dielectric and magnetic properties of the material are taken into account by introducing the Drude-Lorentz model in the materials dispersion. We include multi-band process in the dielectric response in order to reproduce accurately experimental values of bulk Au thin film. Size effect on the dispersion is examined by comparing the model with that of a noble metal particle. Based on the dispersion model constructed, we analyze the electromagnetic response of nanostructured metamaterials to evanescent waves at microwave and optical frequencies via finite-difference time-domain simulatioins on parallel computer. A re- focusing and an amplification of the evanescent waves propagating through a metamaterial, consisting of metal slab/vacuum stacking, is demonstrated for the frequencies of 30GHz and 744THz.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2009-01
Volume volume43
Start Page 8
End Page 15
ISSN 1349-6115
language 英語
File Version publisher
NAID 120002308833
JaLCDOI 10.18926/14061
FullText URL Mem_Fac_Eng_OU_42_56.pdf
Author Miyake Takashi| Totsuji, Chieko| Nakanishi Kenta| Tsuruta, Kenji| Totsuji, Hiroo|
Abstract We analyze the ground state of the two-dimensional quantum system of electrons confined in a parabolic potential with the system size around 100. We map the system onto a classical system on the basis of the classical-map hypernetted-chain (CHNC) method which has been proven to work in the integral-equation-based analyses of uniform unbounded systems and then apply classical numerical simulations. We find that the confined system undergoes the transition to the spin polarized state with the decrease of the average density and the corresponding critical value is as low as rs ∼ 0.3 in terms of the usual rs parameter estimated for the average density. As the ground state for given value of the rs parameter, our data give the critical value for the transition around 20 which is consistent with the known possibility. The advantage of our method is a direct applicability to geometrically complex systems which are difficult to analyze by integral equations. The application to the structure like quantum dots reported here is the first example of such applications.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2008-01
Volume volume42
Issue issue1
Start Page 56
End Page 59
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308633
JaLCDOI 10.18926/14058
FullText URL Mem_Fac_Eng_OU_42_44.pdf
Author Ogawa Takafumi| Tsuruta, Kenji| Totsuji, Chieko| Totsuji, Hiroo| Hiroshi Iyetomi|
Abstract To analyze vibrational properties of Si crystal with a single charge-neutral vacancy, we perform large-scale simulations based on tight-binding molecular-dynamics method. Vibrational modes and frequencies are obtained by diagonalizing dynamical matrix within a harmonic approximation. Results indicate that there exist vibrational modes spatially localized around the vacancy and large frequency shifts associated with the localized modes contribute significantly to reduction of the vibrational free energy.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2008-01
Volume volume42
Issue issue1
Start Page 44
End Page 47
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308412
JaLCDOI 10.18926/14059
FullText URL Mem_Fac_Eng_OU_42_48.pdf
Author Totsuji, Chieko| Miyake Takashi| Nakanishi Kenta| Tsuruta, Kenji| Totsuji, Hiroo|
Abstract Based on the mapping introduced by the classical-map hypernetted-chain (CHNC) method, classical numerical simulations, Monte Carlo and molecular dynamics, have been applied to the twodimensional electron fluid and the results are compared with those of quantum Monte Carlo simulations hitherto reported. It is shown that polarization properties of the ground state obtained by the diffusion Monte Carlo method are reproduced within the accuracy of quantum simulations by both of two mapping functions for the quantum temperature which have been proposed within the CHNC method. These results may serve as the basis of numerical simulations based on the CHNC method which are applicable to finite non-periodic systems like quantum dots and systems at finite temperatures.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2008-01
Volume volume42
Issue issue1
Start Page 48
End Page 52
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308425
JaLCDOI 10.18926/14119
FullText URL Mem_Fac_Eng_OU_40_1_31.pdf
Author Ogawa, Takafumi| Totsuji, Chieko| Tsuruta, Kenji| Totsuji, Hiroo|
Abstract We analyze the melting of spherical Yukawa clusters by Monte Carlo simulations. Spherical clusters are expected to be found in dusty plasmas in an isotropic environment such as microgravity and serve as a model for classical clusters. We obtain the specific heat through fluctuations of the potential energy and identify its peak as the transition temperature. Melting temperatures are compared with those of bulk Yukawa systems and it is confirmed that the melting temperature increases and approaches the bulk value with the increase of the system size.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2006-01
Volume volume40
Issue issue1
Start Page 31
End Page 35
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308329
JaLCDOI 10.18926/14120
FullText URL Mem_Fac_Eng_OU_40_1_36.pdf
Author Uchida, Atsushi| Totsuji, Chieko| Tsuruta, Kenji| Totsuji, Hiroo|
Abstract We present a Stochastic-Difference-Equation (SDE) approach to long time-scale molecular dynamics (MD) simulations, which are required for nanosecond-scale phenomena. In this method, the MD trajectory in a fixed time period is obtained as a stationary solution of an action functional based on an error accumulation of the equation of motion along the path, thus reducing the problem to a boundary-value problem, instead of an initial-value problem in the ordinary MD method. We apply the method to formation processes of Cu thin film via nanocluster deposition onto a substrate. The applicability of the SDE algorithm to the problem and the effects of the choice of SDE parameters on the optimization processes of configuration pathway are examined.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2006-01
Volume volume40
Issue issue1
Start Page 36
End Page 39
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308517
JaLCDOI 10.18926/14121
FullText URL Mem_Fac_Eng_OU_40_1_40.pdf
Author Takashi, Miyake| Totsuji, Chieko| Tsuruta, Kenji| Totsuji, Hiroo|
Abstract The electron system of arbitrary degeneracy can be mapped onto a classical system where electrons of the same spin are assigned an additional interaction and the effect of degeneracy is taken into account through an imaginative temperature. We apply this method to electrons in quantum dots modeled as two-dimensional electron liquid confined in a finite domain by a harmonic potential. We analyze distribution functions by molecular dynamics instead of solving integral equations which are not so useful in the case without translational invariance.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2006-01
Volume volume40
Issue issue1
Start Page 40
End Page 43
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308268
Author Totsuji, Hiroo| Ogawa, Takafumi| Totsuji, Chieko| Tsuruta, Kenji|
Published Date 2005-9
Publication Title Physical Review E
Volume volume72
Issue issue3
Content Type Journal Article
Author Totsuji, Hiroo| Totsuji, Chieko| Ogawa, Takafumi| Tsuruta, Kenji|
Published Date 2005-4
Publication Title Physical Review E
Volume volume71
Issue issue4
Content Type Journal Article
JaLCDOI 10.18926/14150
FullText URL Mem_Fac_Eng_39_1_46.pdf
Author Kadono, Keisuke| Totsuji, Chieko| Tsuruta, Kenji| Totsuji, Hiroo|
Abstract We present a real-space, polynomial-expansion approach to electron dynamics in nanostructured semiconductors. The Chebyshev expansion method is employed for efficient calculation of timeevolution of single-electron wave function. Details of the formulation are described. The method is applied to the electron transport in nanostructured semiconductors such as Si nanowires. The mean-square displacement and diffusivity of electron in Si chains are obtained as functions of length of the chains. The results show clearly ballistic behavior of electron in the pure Si chain.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2005-01
Volume volume39
Issue issue1
Start Page 46
End Page 51
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308231
JaLCDOI 10.18926/14152
FullText URL Mem_Fac_Eng_39_1_52.pdf
Author Kanamori, Katsuya| Totsuji, Chieko| Tsuruta, Kenji| Totsuji, Hiroo|
Abstract Thermal behavior of Coulomb clusters in a three dimensional confining potential is investigated by molecular dynamics simulations for system sizes of 1,000 to 20,288 ions. The specific heat of the system of shell-structured 20,000 ions is peaked almost at the same temperature as the system of bcc-structured 20,288 ions with much sharper structure for the latter. The diffusion coefficient and the peak to valley ratio of the two-dimensional pair distribution function on the outermost shell are obtained both as a function of temperature. The rotational movement of each shell in the system of 104 ions is observed.
Publication Title Memoirs of the Faculty of Engineering, Okayama University
Published Date 2005-01
Volume volume39
Issue issue1
Start Page 52
End Page 55
ISSN 0475-0071
language 英語
File Version publisher
NAID 120002308445