Dear QSIT members
The next QSIT Lunch Seminar will take place on Thursday June 9, at
12:00 noon in the room HPF G6, ETH Hönggerberg, Zurich. There will be
two talks of 30 minutes duration jointly presented by two
collaborators from different research groups. At 13:00 pm free
sandwiches are offered to the participants.
Cotunneling and one-dimensional localization in graphene nanoribbons
Susanne Dröscher, Nanophysics Group, ETH Zurich
and
Optomechancially Induced Transparency
…
[View More]Stefan Weis, Laboratory of Photonics and Quantum Measurements, EPF
Lausanne
Abstracts: http://www.nccr-qsit.ethz.ch/news/lunchseminar/june2011
Please register for your free sandwich at the following link by
Tuesday June 7, 12:00 noon:
http://doodle.com/ssxp6xwhqu2h4g3f
If you have suggestions on topics or speakers, or would like to
present recent results of your research, please send your information
to Andreas Wallraff or Ilona Blatter.
With best regards,
Andreas Wallraff Ilona Blatter
Professor for Solid State Physics QSIT Coordinator
---------------------------------------------------
ETH Zurich
Dr. Ilona Blatter
QSIT Coordinator
Laboratory for Solid State Physics
HPF E 17
Schafmattstrasse 16
8093 Zurich
ilona.blatter(a)phys.ethz.ch
www.nccr-qsit.ethz.ch
Phone: +41 44 633 36 06
Home: +41 44 844 42 50
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Hi everyone,
It will soon be that time of the week again when we congregate in J51 to
listen to glorious tales of scientific breakthrough. This week it will
be the Tale of the Localization of Toric Code Defects, by Cyril Stark.
--Your devoted organizer, Frédéric
--------------------------------------------
Speaker: Cyril Stark
Title: Localization of Toric Code Defects
Date/Time/Place: Tuesday, May 31, 17:00, HIT J51
Abstract:
I will try to sketch the joint project with Renato, Atac and …
[View More]Lode in
which we explore the possibility of passive error correction in the
toric code. We first show that imperfections in the toric code
Hamiltonian lead to logical errors. We then argue that Anderson
localization of the defects, arising from unavoidable fluctuations of
the coupling constants, provides a remedy. This protection is
demonstrated using general analytical arguments that are complemented
with numerical results. The talk is mainly based on arXiv:1101.6028.
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Dear all
Please be informed about the following Optics Colloquium.
With best regards,
Ilona Blatter
------------------------------------------------------------
Invitation to Optics Colloquium next Friday:
Date: Friday, 20.05.11
Time: 14:00
Location: ETH Zurich, Hönggerberg Campus, HCI J-3
Speaker: Tony F. Heinz, Departments of Physics and Electrical
Engineering, Columbia University, New York
Title: Seeing electrons in two-dimensions: Optical sprectroscopy of
graphene
Abstract:
…
[View More]Optical spectroscopy provides an excellent means of understanding the
distinctive properties of electrons in the two-dimensional system of
graphene. Within the simplest picture, one has a (zero-gap)
semiconductor with direct transitions between the well-known conical
bands. This picture gives rise to a predicted frequency-dependent
absorption of pa = 2.3%, where a is the fine-structure constant. We
will demonstrate that this relation is indeed satisfied in an
appropriate spectral range in the near infrared, but that at higher
photon energies electron-hole interactions significantly modify this
result through the formation of saddle-point excitons. Optical
spectroscopy also permits a detailed analysis of how the linear bands
of graphene, corresponding to massless Dirac Fermions, are modified to
yield massive electrons through interlayer interactions in bilayer and
few-layer graphene sheets. The observation of a tunable band gap in
bilayer and trilayer graphene will also be discussed. We will also
discuss recent measurements in which the electron and phonon dynamics
are investigated by ultrafast pump-probe spectroscopy.
Host: Atac Imamoglu, Quantum Photonics, IQE
For a complete OPTICS COLLOQUIUM schedule and up-to-date information
please go to http://www.opteth.ethz.ch/news/optics_colloquium. If you
don’t want to receive this invitation, please send an email to the
above address with the subject line "unsubscribe".
----------------------------------------------------
ETH Zurich
Dr. Andreas Heinle
Coordinator optETH
Laboratory of Physical Chemistry
CH-8093 Zurich, Switzerland
Phone +41 44 633 6871
Fax +41 44 633 1316
www.opteth.ethz.ch
----------------------------------------------------
------------------------------------------------------------------------------------------------------
ETH Zurich
Dr. Ilona Blatter
NCCR QSIT Coordinator
Laboratory for Solid State Physics
HPF E 17
Schafmattstrasse 16
8093 Zurich
ilona.blatter(a)phys.ethz.ch
www.nccr-qsit.ethz.ch
Phone: +41 44 633 36 06
Home: +41 44 844 42 50
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Dear all
Please be informed about the following seminar.
With best regards,
Ilona Blatter
-------------------------------------------------
Date: Tuesday May 17, 2011
Time: 18:00
Place: ETH Science City, HPF G 6
Host: Andreas Wallraff
High-speed optical quantum memories
Klaus Reim
University of Oxford, UK
Abstract:
In a globalised world with ever-increasing, intercontinental
information exchange, there is growing demand for secure communication
technology, such as could be provided by …
[View More]photonic quantum
communications networks. Currently, the biggest challenge for such
networks is distance. Over short distances, photons, interacting only
weakly with their environment, easily and reliably carry quantum
information without much decoherence, but intercontinental quantum
communication will require quantum repeaters embedded in potentially
isolated locations, because photon loss rises otherwise exponentially
with distance. In general, these repeaters will require some sort of
quantum memory, a coherent device where single photons are reversibly
coupled into and out of an atomic system, to be stored, possibly
processed and then redistributed. In order to be practically useful,
this will need to have sufficiently large bandwidth, high efficiency
and long storage time, with multimode capacity, and a low-enough noise
level to enable operation at the quantum level.
I am going to talk about our ensemble-based, far off-resonant Raman
approach to quantum memories, describe how the interaction mechanism
works and show how we store a single photon level signal in the
quantum memory and retrieve it at a controlled later point in time.
Furthermore, I am going to address de-phasing mechanisms for the
stored spin-wave excitation that limit storage times and discuss
storage and retrieval of polarization-encoded qubits.
Publications:
Reim, K. F. et al. Nature Photon. 4, 218-221 (2010)
Reim, K. F. et al. arXiv:1010.3975v1
-------------------------------------------------
ETH Zurich
Dr. Ilona Blatter
NCCR QSIT Coordinator
Laboratory for Solid State Physics
HPF E 17
Schafmattstrasse 16
8093 Zurich
ilona.blatter(a)phys.ethz.ch
www.nccr-qsit.ethz.ch
Phone: +41 44 633 36 06
Home: +41 44 844 42 50
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Hi everyone,
Our next seminar speaker will be Stavros Kousidis. Since he's Matthias's
guest, I'll let Matthias introduce him:
"Dear all,
Next week, Stavros Kousidis will be visiting us and will give a talk in
our seminar. As you can see from the abstract, he is working on rather
abstract representation theory, but in fact, he is developing some
quantum central limit theorems that may be of interest to us!
Matthias"
--Fred, your friendly organizer.
---------------------------------
…
[View More]Speaker: Stavros Kousidis, Universität zu Köln
Date/Time/Place: Tuesday, May 17, 17:00, HIT J51
Title: Statistics of graded tensor product multiplicities
Abstract: Dimensions of invariant subspaces inside tensor products with
respect to some group action are of actual interest. We will make the
problem harder by discussing graded tensor products, which replace the
dimensions in question by polynomials. Interesting symmetries appear in
this graded setting, e.g. a conjectured Gaussian behaviour under some
limit considerations. It sounds heavy, but the talk will start by
introducing irreducible representations of SU(2). My aim is to ignore
any technicality that appears along the way, and rather to deliver a
feeling of what's going on.
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Dear NCCR QSIT colleagues and students,
you and your group members are cordially invited to participate in the
international conference on Quantum Information Processing and
Communication (QIPC) 2011 to be held at ETH Zurich from September 5-9,
2011.
The program committee has selected an exciting range of speakers
covering the diverse aspects of the field of quantum information
science and technology. Detailed information about the conference is
available at the website www.…
[View More]qipc2011.ethz.ch.
In addition to the set program the possibility is offered to submit
abstracts to be selected as hot topic talks held in the plenum or
contributed talks presented in parallel sessions. Abstracts for poster
presentations may be submitted too.
Registration and abstract submission deadlines are May 15, 2011.
Please consider registering for the conference now to secure your
participation in this event which in past years has reached its
capacity limits.
Prior to the conference, we are hosting a QIPC 2011 School in the
Swiss Alps that is aimed at introducing early stage graduate students
to the main research topics of the conference. Lecturers are listed on
the conference web site. Interested students are requested to apply
through the conference web site. Students must register for the main
conference too.
We also invite you to draw the attention of students and colleagues to
the QIPC 2011 conference and school which strives to bring together
leading scientist and young researchers alike.
We are looking forward to welcoming you to Zurich
With best regards
Andreas Wallraff and Atac Imamoglu,
for the organizing and program committees
--
Andreas Wallraff
Professor for Solid State Physics
ETH Zurich
Department of Physics
HPF D 8/9
Schafmattstr. 16
8093 Zurich
Switzerland
+41 44 633 75 63 (office)
+41 44 633 76 17 (secretary)
+41 44 633 14 16 (fax)
andreas.wallraff(a)phys.ethz.ch
http://www.qudev.ethz.ch/ - group's home page
http://www.solid.phys.ethz.ch/ - Laboratory for Solid State Physics
http://www.phys.ethz.ch/ - Department of Physics
http://www.ethz.ch/ - ETH Zurich
---------------------------------------------------
---------------------------------------------------
ETH Zurich
Dr. Ilona Blatter
NCCR QSIT Coordinator
Laboratory for Solid State Physics
HPF E 17
Schafmattstrasse 16
8093 Zurich
ilona.blatter(a)phys.ethz.ch
www.nccr-qsit.ethz.ch
Phone: +41 44 633 36 06
Home: +41 44 844 42 50
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Dear all
Please be informed about Vanessa Wood's introductory lecture.
With best regards,
Ilona
---------------------------------------------------
Date: Wednesday May 11, 2011
Time: 17:15
Place: ETH main building, HG F 30 (Audi Max)
Nanoelectronics - Bringing the Ultra-small to Batteries, LEDs, and
other Devices
Vanessa Wood
Departement of Information Technology and Electrical Engineering, ETH
Zurich
Introductory lecture: http://www.ethz.ch/news/lectures/index_EN
------------------…
[View More]---------------------------------
ETH Zurich
Dr. Ilona Blatter
NCCR QSIT Coordinator
Laboratory for Solid State Physics
HPF E 17
Schafmattstrasse 16
8093 Zurich
ilona.blatter(a)phys.ethz.ch
www.nccr-qsit.ethz.ch
Phone: +41 44 633 36 06
Home: +41 44 844 42 50
[View Less]
Dear all
Please be informed about the Physics Colloquium next week.
Amir Yacobi will be in Zurich on Tuesday and on Wednesday.
With best regards,
Ilona Blatter
---------------------------------------------------
Date: Wed May 11, 2011
Time: 16:45 (coffee and tea at 16:15)
Place: ETH Science City, HPV G 4
Host: Thomas Ihn
Quantum Information Processing and Metrology Using Few Electron Spins
in Solids
Amir Yacobi
Department of Physics, Harvard University, USA
abstract: http://www.…
[View More]colloquium.phys.ethz.ch/program/Yacobi_pdf
---------------------------------------------------
ETH Zurich
Dr. Ilona Blatter
NCCR QSIT Coordinator
Laboratory for Solid State Physics
HPF E 17
Schafmattstrasse 16
8093 Zurich
ilona.blatter(a)phys.ethz.ch
www.nccr-qsit.ethz.ch
Phone: +41 44 633 36 06
Home: +41 44 844 42 50
[View Less]
Dear all
Please be informed about the following informal seminar.
With best regards,
Ilona Blatter
---------------------------------------------------
Date: May 5, 2011
Time: 10:00
Place: HPT G 18
Host: Atac Imamoglu
Majorana fermions via dissipation
Sebastian Diehl
University of Innsbruck
---------------------------------------------------
ETH Zurich
Dr. Ilona Blatter
NCCR QSIT Coordinator
Laboratory for Solid State Physics
HPF E 17
Schafmattstrasse 16
8093 Zurich
ilona.blatter(a)phys.…
[View More]ethz.ch
www.nccr-qsit.ethz.ch
Phone: +41 44 633 36 06
Home: +41 44 844 42 50
[View Less]
Hi everyone,
The next episode of our group seminars next Tuesday will feature a talk
by Christopher Portmann. Do not miss it!
--Frédéric
---------------------------------------
Title: Information-theoretic non-malleable encryption.
Date/Time/Place: Tuesday, May 10, 17:00, HIT J51
Speaker: Christopher Portmann
Abstract:
An encryption scheme is said to be non-malleable, if no adversary can
modify a ciphertext so that the resulting message is meaningfully
related to the original message. In …
[View More]the first part of the talk, I'll
give the same presentation as at the upcoming ICITS on the classical
case (eprint.iacr.org/2011/092). In the second part of the talk I'll
review the work by Ambainis, Bouda and Winter (arXiv:0808.0353) on
quantum non-malleability.
We compare information-theoretic non-malleability for classical schemes
to secrecy and authenticity, and provide a complete characterization of
their relative strengths. In particular, we show that
information-theoretic perfect non-malleability is equivalent to perfect
secrecy of two different messages. This implies that for $n$-bit
messages a shared secret key of length roughly $2n$ is necessary to
achieve non-malleability, which meets the previously known upper bound.
We define approximate non-malleability by relaxing the security
conditions and only requiring non-malleability to hold with high
probability (over the choice of secret key), and show that any
authentication scheme implies approximate non-malleability. Since
authentication is possible with a shared secret key of length roughly
$\log n$, the same applies to approximate non-malleability.
Ambainis et al. study non-malleable encryption for quantum messages, but
restrict their considerations to encryption operations consisting in
unitary transformations. They show that such a scheme is equivalent to a
"unitary 2-design", as opposed to normal encryption which is a unitary
1-design.
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