First-principles electronic structure calculation
for K-doped coronene, which is the second aromatic
superconductor after K-doped picene reported by
Kubozono's group, has been published as
Taichi Kosugi, Takashi Miyake, Shoji Ishibashi,
Ryotaro Arita and Hideo Aoki:
Electronic structure of solid coronene: differences and commonalities to
picene,
Phys. Rev. B 84, 020507(R),
which is also selected as an Editors' Suggestion.

The paper,
Naoto Tsuji, Takashi Oka, Philipp Werner and Hideo Aoki:
Changing the interaction of lattice fermions dynamically
from repulsive to attractive in ac fields,
in which we have shown theoretically that a sudden application of an
intense ac field to correlated lattice fermions
effectively switches the interaction from repulsive to attractive,
accompanied by a negative temperature (population inversion), which
in turn suggests a possibility of dynamically induced
superconductivity, has been published in Phys. Rev. Lett. 106,
236401 (2011).  The paper has been selected as an Editor's suggestion,
and also introduced by
James K. Freericks:
Changing repulsion into attraction with the quantum Hippy Hippy Shake,
Physics 4, 45 (2011)
http://physics.aps.org/articles/v4/45
as a Viewpoint article.

A video and the slides of the
talk given by Aoki at IPMU Focus Week "Condensed Matter
Physics Meets High Energy Physics" held on 8-12 February, 2010,
has been posted at a web page
http://member.ipmu.jp/cmphep2010/

A theoretical idea for realising the Nagaoka-like
ferromagnetism in a ladder structure for cold atoms
in optical lattices has been published as
M. Okumura, S. Yamada, M. Machida and H. Aoki:
Phase-separated ferromagnetism in spin-imbalanced Fermi atoms
Loaded on an optical ladder--- a DMRG study,
Phys. Rev. A 83, 031606(R) (2011).

A review on the quantum Hall effect,
Hideo Aoki: Integer quantum Hall effect,
is now published as a chapter in
Hiroshi Kamimura (ed.):
  Comprehensive Semiconductor Science & Technology (Elsevier, 2011).

Our work,
Y. Ota, M. Machida, T. Koyama and H. Aoki:
Leggett's collective modes in multiband superfluids and
superconductors --- Multiple dynamical classes, arXiv:1008.3212,
in which three-band superconductors are shown to have
multiple collective (Leggett) excitation modes
with different masses, with an instability when the three
kinds of gauge-symmetry breaking are "frustrated" ,
has been published in Phys. Rev. B 83, 060507(R) (2011).

colloqium
Lecturer: Philipp Werner (ETH Zurich)
Title: "Interaction quenches and ramps in the Hubbard model"
Date: 2011/ 1/ 24(Mon) 16:00 - 17:30
Place: Rm 233 at Bld 1

[2010]
colloqium
Lecturer: Takuya Kitagawa (Harvard University)
Title: "Topological characterization of periodically driven systems "
Date:2010/ 12/ 17(Fri) 17:00 - 18:30
Place:Rm 933 at Bld 1


While a massless Dirac particle has
half-integer quantum-Hall topological numbers,
known as an anomaly, it is interesting to
ask whether the quantum Hall
effect in lattice models can be decomposed into a half-integer
contributions from each Dirac cone.  A study on this
(Haruki Watanabe, Yasuhiro Hatsugai and Hideo Aoki:
Half-integer contributions to the quantum
Hall conductivity from single Dirac cones,
(arXiv:1008.0130))
has been published in Phys. Rev. B 82, 241403(R) (2010).


colloqium
Lecturer: Koich Kusakabe (Osaka University)
Title: "Pair-Hopping Mechanism for Layered Superconductors"
Date:2010/ 10/ 12(Tue) 14:00 - 
Place:Rm 933 at Bld 1


colloqium
Lecturer: Martin Eckstein (ETH)
Title:"Dynamical mean-field theory for the real-time evolution of correlated electron systems"
Date:2010/ 9/ 6(Mon) 15:00 - 16:30
Place:Rm 933 at Bld 1


colloqium
Lecturer: Werner Dietsche（Max-Planck-Institut fur Festkorperforschung）
Title:"The Exciton Condensate in Quantum-Hall Bilayers" 
Date:2010/ 8/ 10(Tue) 16:00 - 17:30
Place:Rm 933 at Bld 1
 
A two-orbital study
[Hirofumi Sakakibara, Hidetomo Usui,
Kazuhiko Kuroki, Ryotaro Arita and Hideo Aoki:
Two orbital model explains
why the single-layer Hg cuprate have higher
superconducting transition temperature than the La cuprate]
(arXiv:1003.1770)
on the long-standing puzzle on why the single-layered cuprate
HgBa2CuO4+x (Tc~90K) has such a higher Tc than
La2-x(Sr/Ba)xCuO4 (Tc~40K)
has been published in Phys. Rev. Lett. 105, 057003 (2010) . 

An experiment in Professor Shimano's laboratory
[Y. Ikebe, T. Morimoto, R. Masutomi, T. Okamoto, H. Aoki and R. Shimano:
Optical Hall Effect in the Integer Quantum Hall Regime]
(arXiv:1004.0308)
jointly written with our theoretical group has
detected the "Optical Hall effect" (namely, the optical Hall conductivity
in the THz regime in the quantum Hall systems), which
has been theoretically predicted by
Takahiro Morimoto, Yasuhiro Hatsugai and Hideo Aoki:
Optical Hall conductivity in ordinary and graphene QHE systems,
Phys. Rev. Lett. 103, 116803 (2009).
The experimental paper is now published in 
Physical Review Letters 104, 256802 (2010).


Following the publication of the experimental work by Kubozono's group
on the discovery of the first aromatic superconductor as
R. Mitsuhashi et al, Nature 464, 76 (2010) on 4 March 2010,
the theoretical work on this material by Aoki's group
has been press released at
http://www.s.u-tokyo.ac.jp/press/press-2010-08en.html

IPMU Focus Week "Condensed Matter Physics Meets High
Energy Physics" has been held in February 2010, co-chaired
by Aoki and Professor Hiroshi Ooguri
（Caltech/IPMU).  For details, visit
http://www.theory.caltech.edu/~ooguri/CMP-HEP/CMP-HEP.htm


[2009]

A paper on the electronic structure of the
doped solid picene, the first aromatic organic
superconductor discovered by a group led by
Professor Kubozono of Okayama University,
has been published:
Taichi Kosugi, Takashi Miyake, Shoji Ishibashi, Ryotaro Arita
and Hideo Aoki:
First-Principles Electronic Structure of Solid Picene,
J. Phys. Soc. Jpn 78, 113704 (2009)
(arXiv:0910.3022).


colloqium
Lecturer:P. Werner (ETH)
Title:"Monte Carlo approach to transport and non-equilibrium problems"
Date:2009/ 10/ 20(Tue) 13:00 - 14:30
Place:Rm 447 at Bld 1
 
colloqium
Lecturer:Shin-ichiro Ideta (Science Faculty, Tokyo University)
Title:"ARPES study of the tri-layer Cuprate superconductor Bi2Sr2Ca2Cu3O10+d"
Date:2009/ 10/ 19(Mon) 15:30 - 17:00
Place:Rm 933 at Bld 1 

Our work that has analysed the anomalous behaviour of the
Landau level at the Dirac point in the graphene quantum
Hall effect,
Tohru Kawarabayashi, Yasuhiro Hatsugai, Hideo Aoki:
"Quantum Hall plateau transition in graphene with correlated random
hopping" (arXiv:0904.1927)
has been published in Phys. Rev. Lett. 103, 116803 (2009).

The Letter has also been
highlighted in a Synopsis on the Physics website
with the link to the Synopsis:
 http://physics.aps.org/synopsis-for/10.1103/PhysRevLett.103.156804


The paper on the ac (optical) response of the quantum
Hall systems,
Takahiro Morimoto, Yasuhiro Hatsugai and Hideo Aoki:
Optical Hall conductivity in ordinary and graphene QHE systems
(arXiv:0904.2438)
has been published in Phys. Rev. Lett. 103, 116803 (2009).
Press Releases

University of Tokyo Museum exhibition
"Iron, the core of existence through the
history of 13.7 billion years",
to which Professor Aoki has contributed,
is now open.
					
The paper on nonequilibrium states that are created
when an intense laser is irradiated to strongly correlated
electron systems
(Naoto Tsuji, Takashi Oka, and Hideo Aoki:
Nonequilibrium steady state in photoexcited correlated electrons with
dissipation, arXiv:0903.2332)
has been accepted for publication in Phys. Rev. Lett. 103, 047403 (2009)
                    
GCOE (Global Center of Excellence) seminar
Lecturer:Prof. P. A. Maksym ( University of Leicester, Leicester, UK)
itle:"Electron confinement in graphene quantum dots"
Date:2009/ 7/ 13(Mon) 16:00 - 
Place:Rm 933 at Bld 1                     
                    
A theoretical paper [a full paper to PRL 101, 087004 (2008)]  on the new iron-based superconductor,
Kazuhiko Kuroki, Hidetomo Usui, Seiichiro Onari, Ryotaro Arita and Hideo Aoki:

Pnictogen height as a possible switch between high-$T_c$ nodeless and low-$T_c$ nodal pairings in the iron based superconductors, 
Phys. Rev. B 79, 224511 (2009)

has been selected by the editors of PRB to be an "Editors' Suggestion". (June 2009)
(external link to APS )