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Seminar - Population transfer between quantum states to perfection: Stimulated Raman Adiabatic Passage (STIRAP) (23-05-2013)
23/05/2013, 15:00 Sala P3.10, Mathematics Building, IST.
In many areas of science (e.g. physics, chemistry, quantum information) controlled modification and in particular efficient transfer of population between quantum states is wanted. Many schemes are known that allow varying the usually thermal population distribution. Of particular interest are means for selective and efficient transfer of population from quantum state i to quantum state f. “Efficient” means that nearly 100% of the population residing initially in state i reaches state f. This also implies high selectivity as no other quantum state receives population. Traditional techniques such as Raman scattering, optical pumping or stimulated emission pumping fail to reach the goal. Spontaneous emission, which channels population into other levels,is a main problem. STIRAP solves that problem through a surprisingly simple, but at first glance very puzzling, sequence of radiative interactions: The quantum system is first exposed to the radiation field which connects the final state with an intermediate state (thus, it does not couple to the quantum state which carries initially the population) before the second radiation field couples the initial state to the same intermediate one. The basic phenomena and the physics building blocks of this process, the concept of which is now applied in very many areas, are presented and explained.
Quantum Computation and Information Seminar
Support: Phys-Info (IT), SQIG (IT), CFIF and CAMGSD, with support from FCT, FEDER and EU FP7, namely via projects PTDC/EEA-TEL/103402/2008 QuantPrivTel, PEst-OE/EEI/LA0008/2013 and Landauer (GA 318287).
Completeness and interpolation of almost-everywhere quantification over finitely additive measures (24-05-2013)
Joao Rasga, SQIG-Instituto de Telecomunições / IST-Universidade de Lisboa
May 24, 2013, Friday, 16h15m.
Abstract: We give an axiomatization of first-order logic enriched with the almost-everywhere quantifier over finitely additive measures. Using an adapted version of the consistency property adequate for dealing with this generalized quantifier, we show that such a logic is both strongly complete and enjoys Craig interpolation, relying on a (countable) model existence theorem. We also discuss possible extensions of these results to the almost-everywhere quantifier over countably additive measures. The talk reports on joint work with Wafik Lotfallah and Cristina Sernadas.
Room: 3.10, Mathematics
Support: SQIG/Instituto de Telecomunicações with support from FCT and FEDER namely by the FCT project PEst-OE/EEI/LA0008/2013.
IEEE International Workshop on Immersive & Interactive Multimedia Communications over the Future Internet (09-06-2013)
Organized in conjunction with
IEEE International Communications Conference (ICC 2013)
9-13 June 2013, Budapest, Hungary
Registration of abstract: January 4, 2013
Manuscript submission: January 11, 2013
Acceptance Notification: February 2, 2013
Camera-ready: March 8, 2013
This workshop targets novel issues in immersive media networking where IP offers flexibility in designing novel optimal communication systems
for various multimedia data representations and encoding schemes. Transmission and adaptation of coded media to cope with heterogeneous communication networks, diverse terminal equipment and user interaction is an open topic where sound contributions are expected. The workshop will include both service personalisation
and QoS/QoE (Quality of Service/Quality of Experience) assurance by seeking for efficient solutions in the fields of : i) server-side adaptation,
for optimisation of one-to-many single-stream media content, such as multicast streaming; ii) In-network adaptation, where multimedia streams, especially 3D streams, are processed by the network elements themselves, an approach that is best suited for multicast traffic, where different delivery paths may have different capacities;
and iii) Client-side adaptation, in the case where dissimilar media streams are to be re-transmitted or re-distributed in a local manner (e.g., within a home network).
Novel QoE-aware networking frameworks are also addressed, where innovative adaptation and congestion control mechanisms are devised to optimise multimedia delivery over future media networks across heterogeneous and diverse environments. Since QoE is not only influenced by dynamic networking conditions, but also by the quality and perceptual relevance of each element of the coded source stream (e.g., stereoscopic view, audio channel), cross-layer methods shall be devised in order to make QoE metrics available to network control and adaptation mechanisms. The workshop will consider the ecosystem for the delivery of Media Content across ubiquitous networking environments. This includes heterogeneous wireless networks (e.g. WLAN, WiMAX, LTE, 4G), Broadcasting (e.g. DVB), IP-based networks (e.g. information
centric networks, P2P) as well as Future Internet Media architectures.
Major topics of interest:
• Future Media Internet architectures
• Information Centric Networks for Immersive Media
• QoE modeling, evaluation, monitoring and control
• Scalable multimedia coding
• Multiple multimedia descriptions for wireless communications
• Surrounding, immersive and interactive multimedia environments
• Community-focused interactive media systems
• Scalable video coding for wireless communication channels
• Transcoding for heterogeneous wireless channels interoperability
• Mobile multimedia multicast
Submitted papers must represent original material which is not currently under review in any other conference or journal and has not been previously published.
Paper length should not exceed five-pages standard IEEE conference two-column format (including all text, figures, and references).
To submit follow the instructions on:
Pedro Assuncao, Instituto de Telecommunicações, Portugal
Luigi Atzori, University of Cagliari, Italy
Tasos Dagiuklas, TEI of Mesolonghi, Greece
Ahmet Kondoz, University of Surrey, UK