2019 研究テーマテーマ

方法

題目

DFT

Schottky barrier in 2D-transistor material:
Te / MoTe2 interface
Exchange bias system. Structure andmagnetism of Mn islands on Fe(110)
Molecular coupling effect on ARPES oforganic molecules: Mn phthalocyanine
ARPES of hexagonal boron nitride/Cu(111)DFT
DFT+scattering
DFT+
scattering
Programming
Multiplet

共同研究

青木研
山田研
解良研
Jülich (D)Calculation of scattering matrix for arbitrary 富山大
potential shape
Theory of X ray absorption spectra fromtransition metal atoms in chiral molecules
Statistical Thermodynamics of alloys from pairDijon (F)mechanics distribution function / X-ray diffraction dataDFT-AI
Make algorithm for finding adsorption site 先進ｾﾝﾀｰｾﾝﾀｰ
from charge density w/o SCF calculation

Schottky barrier in 2D-transistor material:
Te / MoTe2 interface●

MoTe2 = new 2D
semiconductor

Te●

Laser irradiation → doping, phase transition●

Strong laser → phase separation Te-Mo→ formation of semi-metallic Te→ reduction of Schottky barrier at electrode●Te / MoTe2 interface structure unknown→ ab initio modeling

Structure and magnetism of islanded Mn/Fe(110)背景：
山田先生がが Fe(110) 基板に吸着されたに吸着された吸着されたされたMn 一層の薄膜・ナノアイランドを作成の薄膜・ナノアイランドを作成薄膜・ナノアイランドを作成ナノアイランドを作成を作成作成した。
強磁性体・ナノアイランドを作成反強磁性体の薄膜・ナノアイランドを作成界面はスピンはスピンスピン
Valve 等のの薄膜・ナノアイランドを作成 spintronics デバイスで使わ使わわれる。
課題：１） Mn 一層の薄膜・ナノアイランドを作成の薄膜・ナノアイランドを作成薄膜験の構造・電子状態の薄膜・ナノアイランドを作成構造・ナノアイランドを作成電子状態・ナノアイランドを作成スピン構造を作成 DFT で使わ計算する。する。
２）ナノ島の安定さ、新構造を求める。の薄膜・ナノアイランドを作成安定さ、新構造を求める。さ、新構造を求める。新構造を作成求める。める。
林氏（山田研）卒論

Europhys. Lett., 46, 231-237 (1999)
Parallel, antiparallel and no magnetic
coupling in submonolayer Mn on
Fe(110)O. Rader , C. Pampuch, W. Gudat, A.
Dallmeyer, C. Carbone and W.
Eberhardt
In this letter, we report on three
intriguing coupling effects occurring inthe same systemand sample: i) absence of coupling in
the low-coverage limit, which has
never been reported
before, ii) parallel coupling from 0.4 to
2 ML, contrasting our findings on the(100) surface ofantiparallel coupling vanishing at 1 ML,and iii) a surprising reversal toantiparallel couplingby oxygen dosage. We will discuss
explanations for the first two in detail,the oxygen effect,
however, remains much lessunderstood.

J. Phys.: Condens. Matter 28 (2016) 326001
doi:10.1088/0953-8984/28/32/326001
Noncollinear magnetism of Mn nanowires
on Fe(1 1 0)
R N Igarashi , I P Miranda, L T F Eleno, A B
Klautau and H M Petrilli

ARPES of 2-layer Mn-phthalocyanine
Molecular coupling effect on ARPES of organic molecules:
Mn phthalocyanine

To do:
1) reproduce 1 monolayer → 石川さんの修論 さんの薄膜・ナノアイランドを作成修論
2) make model for 2 layer
Compute ARPES as a function of structure
Calc: Gaussian + Multiple scattering program (PK)Exp: 良解先生がRefs 石川さんの修論 さんの薄膜・ナノアイランドを作成修論
P Krüger, J. Phys. Soc. Japan 87, 061007 (2018)

P Krüger, J. Phys. Soc. Japan 87, 061007 (2018)

ARPES h-BN/Cu(111)Objective: energy dependence of sigma and pi bands.
Comparison of different methods:- plane wave approximation (VASP → 前川さんの修論 、新構造を求める。小野さんさん )- multiple scattering calculation (with LMTO band structure/potentials → 藤方さん）  さん）hBN/Cu(111)

Confidential data

Regarding BN, we have done something on hBN/Cu(111) and hBN/SiC(0001). For both - NIXSW (adsorption height) and LEED. ARPES ofhBN/Cu(111) is quite known, we have also done it with UV lamp (40 eV) and soft x-ray (110 eV). It general we are planning to measure at some point
either/or these systems using our toroidal analyser. This would mean angle of incidence of 40° from normal (or different, can be varied from normal
incidence to at least 60°) collecting electrons emitted in the scattering plane in +- 85° emission angle and then rotating sample around its normal. Mostinteresting here can be the photon energy dependence - one can compare sigma and pi bands intensities.

Sergej Subach, Julich, Germany, Private Communication --- CONFIDENTIAL

h-BN/Ni(111)Study of the Electronic Structure of hexagonal Boron Nitride on Metals Substrates
Paul Giraud, Master thesis, Univ Lille, 2003.

nano-bio.ehu.es/files/paulgiraud_masterthesis.pdf

Calculation of scattering matrix for arbitrary potential shapeV2O5

計算実験

X 線吸収理論
経験的なパラメータなしの多重項モデルなパラメータなしの多重項モデルパラメータなしの多重項モデルなパラメータなしの多重項モデルしの多重項モデル多重項モデルモデル
DFT
状態密度

配位子場b2ea1b1多重項モデル理論

EPDOS

b1 x2-y2計算

a1 3z2-r2-6-4-20
relative photon energy(eV)

24e zx,yz
b2 xyCo-Pc

偏光面内面直実験

X 線エネルギーD) Theory of finite volume fluctuations in fluids
Thermodynamic response functions, e.g. compressibility, relate to particle
fluctuations and can be calculated as infinite volume [“Kirkwood-Buff”]
integrals over pair correlation function h(r)We have generalized Kirkwood-Buff theory to finite volumes and solved thelong standing problem of slow integral convergence

Analytic weight functions w(r,V)∞2G(∞)=∫0 h(r) 4 π r drG(V )=∫V d r 1∫V d r 2 h(|r 1−r 2|)L=∫0 h(r )w (r , V )drStandard truncatedintegral (G0) vs exact
finite volume (G) andnew extrapolations(G1,G2) to ∞

Application to crystals:
Madelung constantspherical shell summation→ divergence

finite volumeKBI method→ fast convergenceThermodynamics of alloys from pair-distributionfunction / X-ray diffraction data1) Application of fluctuation theory to finite crystalline nanoparticles ofspherical or cubic shape with simple cubic, bcc, or fcc structurea) generate RDF for perfect crystalb) apply finite volume Kirkwood-Buff integral theory to compute Gij andcompressibility as a function of cluster sizeb) compare with liquid and bulk crystal
2) Alloy theorya) Generate model pair distribution function with Monte Carlo simulation andapply KB theoryb) apply theory to experimental structure factor / PDF
Refs:
P.K. et al. J. Phys. Chem. Letters 4 (2013) 235.
P.K. and T.J.H.Vlugt. Phys Rev. E 97 (2018) 051301