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Research Highlights 2012

EPFL RESEARCH HIGHLIGHTS 2012

Research at the EPFL

EPFL is one of the leading universities in basic, applied, and interdisciplinary sciences and we

are committed to providing our faculty with world-class research facilities, the most advanced

equipment, and ample administrative support regarding grants, logistics, and human

resources. The research being conducted here and institution’s atmosphere and infrastructure

have been attracting talent from all over the world. As the Dean of Research I make a special

effort with my team to nurture our junior researchers. To help them thrive at the EPFL we also

offer start-up packages to new members of our community.

In this first edition I am very proud and delighted to present some research highlights of our

faculty. These impressive and groundbreaking results run the gamut from quantum effects in

physics to understanding the human brain, modeling prevailing environmental problems, as

well as much more.

I would like to thank the central service and research affairs staff for their dedicated support

and initiative in the creation of this brochure.

Again, the following pages present just a few examples of current work being conducted by our

brilliant faculty, and I look forward to introducing more inspiring work in the upcoming issues.

EPFL Dean of Research

Prof. Benoit DEVEAUD-PLÉDRAN

Finding solutions for a sustain-

able future

The mission of the School of

Architecture, Civil, and Environ-

mental Engineering (ENAC) is to

provide excellent undergraduate

and graduate level education and

conduct research into innovative

solutions for the world’s most

pressing environmental issues:

population growth and the emer-

gence of megacities; increasing

land, energy, and transportation

needs; maintenance and

improvement of the built envi-

ronment; conservation of natural

resources and biodiversity; and

the management of natural and

manmade hazards.

ENAC Faculté de l'Environnement Naturel, Architectural et Construit

Bringing mathematical modeling into mainstream epidemiology

“At the start of the project, we had a clear idea about the directions to pursue. We began by studying rivers as ecological corridors for species – how river networks and the management of water resources affect biodiversity for example. We also studied how landscape heterogeneities have affected historic population migrations. But our research rapidly developed and entered unexpected fields. For instance, we began to explore how far we can go in predicting epidemics of waterborne diseases, including endemic and epidemic cholera, and now this is a major research line of the Lab."

Cholera is one of the world's most virulent infectious diseases, and it thrives in areas with little or no access to safe drinking water or adequate sanitation. The team of Prof. Rinaldo is working on an interdisciplinary project that focuses on large-scale cholera epidemic modeling and its use for the emergency management of control measures. His area of expertise (i.e. bringing mathematical modeling into mainstream epidemiology) is perceived to be a key research domain for years to come.

This research is proving indispensable for predicting the space-time evolution of infections, including the instantaneous local values of severely/asymptomatic infected or susceptible individuals, which is crucial to public health and intervention strategy management.

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Prof. Andrea RINALDOLaboratory of Ecohydrologie

echo.epfl.ch

School of Architecture, Civil and Environmental Engineering

These techniques facilitate the deployment of life-saving medical supplies and staff and the optimization of control measures like mass

vaccinations, the intelligent use of antibiotics, and the reduction of exposure rates due to sanitation improvement, access to clean

drinking supplies, mobility restrictions, etc.

ECHO is coping with a problem whose relevance has been brought to the world's attention recently by the massive cholera outbreak in

Haiti. The severity of this epidemic made clear the dimensions of the social, economic and humanitarian problems involved.

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The School of Computer and Communication Sciences is one of the main European centers for education and research in the field of computer, information and communication sciences. Its research includes interdisciplinary projects with a wide variety of programs across campus and with other universities and is funded by the Swiss Confederation, European Union, as well as a number of private foundations and industrial partners.Research activities span the following areas: Algorithms & Theoretical Computer Science, Artificial Intelli-gence & Machine Learning, Compu-tational Biology, Computer Archi-tecture & Integrated Systems, Data Management & Information Retrieval, Graphics & Vision, Human-Computer Interaction, Information & Communi-cation Theory, Programming Languages & Formal Methods, Security & Cryptography, Signal & Image Processing, Systems & Networks.

IC Faculté Informatique et Communications

Massive number crunching to secure the Internet

Protecting information used to be something that only governments would worry

about. These days it affects everyone. Seamlessly integrated with our quickly

growing communications infrastructure is a wide array of security mechanisms

that, transparent to the user, are meant to keep eavesdroppers at bay.

At EPFL's School of Computer and

Communication Sciences, the team of

Prof. Lenstra studies how to adequately

protect data in an economically viable

manner. This involves research in many

different areas, ranging from

mathematics, algorithm design and

analysis, and implementations that

optimally exploit the characteristics of the

underlying hardware, to identifying bad

practices before they can be exploited by

hackers.

Since its inception in 2006, the Laboratory for Cryptologic Algorithms (LACAL)

has substantially contributed to maintaining Internet security by combining new

mathematical insights, innovative applications of commodity hardware, and

advanced implementation techniques.

Prof. Arjen LENSTRALaboratory for Cryptologic Algorithms

lacal.epfl.ch

School of Computer and Communication Sciences

For instance, in 2008 the lab's cluster of more than 200 PlayStation 3 game

consoles made headlines when it was used to create a proof of concept rogue

certification authority, thereby convincing the key players in the security industry

to abandon a particular commonly used method that was known to be insecure.

More recently, the lab's disclosure of a widely spread problem affecting a popular

encryption tool was featured in the world press. Furthermore, many record

calculations have been performed over the past years on the lab's computer

clusters – calculations that take years on thousands of cores are not uncommon

– and have triggered the adoption of more secure cryptographic standards.Moduli that share no or both prime factors Moduli that share one prime factor

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The mission of the School of

Basic Sciences (SB) is to create

new knowledge that forms the

basis of next generation

technologies, find scientific

solutions to real-world problems,

educate and train the next

generation of scientists and

engineers, and foster innovation

for economic growth via

activities ranging from curiosity

driven research to device

oriented applications.

In the context of this mission, we

seek to become one of the top

five research universities in

Europe.

SB Faculté des Sciences de Base

Optical microresonators

Systems with small dissipation have unique properties. The Laboratory of Photonics and Quantum

Measurements is studying ultra low loss optical microresonators for new physics and technological

applications.

In 2007 the Laboratory of

Photonics and Quantum

Measurements discovered

that such optical micro-

resonators can generate

optical frequency combs

(Del Haye et al Nature

2007). Optical frequency

combs are a revolutionary

tool for precision measure-

ments and were invented

by Theodor W. Hänsch

(Nobel Prize in Physics in 2005).

While conventional frequency combs are based on complex and bulky femtosecond lasers, optical

microresonators enable a dramatic reduction in size and fiber optic integration of the latter.

The k-lab is presently researching this novel principle in order to explore new ways of generating

frequency combs in the molecular fingerprinting region (mid IR) or for advanced multichannel

telecommunications sources.

The high power inside a microresonator also enables the study of the complex physics involved in

radiation pressure. Predicted in 1970 the optomechanical coupling that occurs between mechanical

motion and the light field can be used to realize laser sideband cooling using backaction and bears

similarity to atomic laser cooling. The Laboratory of Photonics demonstrated this technique for the first

time (Schliesser et al. Phys. Rev. Lett. 2006) and used it to cool mechanical oscillators to nearly

absolute zero. At these ultra low temperatures the mechanical oscillator occupies its quantum

mechanical ground state with high probability (Verhagen, Nature 2012).

These studies aim at demonstrating that micro- and nanomechanical oscillators coupled to light fields

can serve as a new quantum technology, enabling the storage of optical information in mechanical

vibrations for instance. Moreover these studies allow for the study of the most fundamental quantum

mechanical oscillator: a mechanical vibration.

Prof. Tobias KIPPENBERGLaboratory of photonics and quantum measurements

k-lab.epfl.ch

School of Basic Sciences

The high quality of the scientific

publications and the large

number of successful patent

applications that emanate from

the School of Engineering (STI)

laboratories attest to the

recognition of the international

academic community and the

interest of industrial partners in

its work.

With 1275 employees, 1020

undergraduates, 547 Masters

students and 657 doctoral

candidates, and an annual

budget of 80 million Swiss

Francs, STI possesses both the

competencies as well as the

means to bring a broad range of

multidisciplinary projects to a

successful conclusion.

STI Faculté de Sciences et Techniques de l'Ingénieur

A new promising material for electronics

The miniaturisation of transistors, the main building block of electronics, is reaching its limits.

Some effects of these limits became visible in the last decade, when microprocessor clock

frequencies stopped increasing due to problems related to heat dissipation. Replacing silicon with

another material could be a possible solution.

Researchers from the group of Prof. Kis from the Electrical Engineering Institute at EPFL have

recently shown that single molecular layers of mineral molybdenite (chemical formula MoS2) can

be used to build high-performance transistors. This abundant material is mainly used in the steel

industry and is well-known for its lubricating properties. Prof. Kis and his team showed that it is

also an interesting semiconductor. What makes MoS2 attractive for semiconductor devices is its

structure: crystals of this material are composed of layers, 0.65 nm thick, which are stacked on

top of each other like sheets in a block of paper.

School of Engineering

Prof. Andras KISLaboratory of Nanoscale Electronics and Structures

lanes.epfl.ch

Using a simple piece of scotch-tape, the LANES group was able to extract single layers

and build transistors that are extremely power efficient and can be put into a more

complete standby mode than its counterparts made of silicon or graphene.

LANES researchers also demonstrated how simple integrated circuits based on MoS2

were capable of performing logic operations and amplifying voltage. Because of its

atomic-scale thickness, smaller transistors could be made with MoS2 than with silicon,

which can only be made 2nm thick because of problems with oxidation. The same

material could also be used for fabricating solar cells or LEDs.

In future, MoS2 could allow for the development of transistors that are a great deal

smaller and more power-efficient than previously imaginable. MoS2 is also the most

stretchable known semiconductor and could be used for innovative applications requiring

elasticity such as the fabrication of flexible computers, solar cells, or LEDs.

The future of life sciences lies at

the crossroads of biology, medi-

cine, physics, mathematics and

engineering, because today's

challenges in medicine strongly

depend on transdisciplinary app-

roaches.

In line with this goal, the School

of Life Sciences (SV) trains

scientist engineers whose

combined skills in these fields

are set to address fundamental

biological questions and attack

major medical problems of our

times. Researchers in SV apply

this philosophy to broad

questions spanning a wide range

of disciplines and methodologies,

including cancer, infectious

diseases, and neurological dis-

orders.

SV Faculté des Sciences de la Vie

Revealing the mechanisms that translate stress effects on brain and behavior

Stress has major effects on behavior and is a key risk factor for the development of

psychopathologies. Understanding the neurobiological processes involved in how stress

affects brain and behavior can help improve currently insufficient therapeutic approaches to

neuropsychiatric disorders.

The Brain Mind Institute of the School of Life Science’s Laboratory of Behavioral Genetics led

by Prof. Sandi investigates the impact and mechanisms involved in stress effects on learning

and memory, social behaviors and psychiatric disorders – anxiety, depression, and

pathological aggression – as well as individual factors determining vulnerability to stress. This

involves a multidisciplinary program comprising behavioral, pharmacological, molecular,

genetic, epigenetic, metabolic, neuroimaging and mathematical approaches.

School of Life Sciences

One of the key findings of this team was to identify neuronal cell adhesion molecules, which play a

crucial role in the establishment of neuronal contacts, as relevant targets of stress in brain regions

involved in emotion and cognition. They further showed

that pharmacological treatment with small peptides

acting on cell adhesion molecules can improve

cognitive function and induce recovery from stress

effects, highlighting the therapeutic potential of

targeting these molecules.

Currently, the lab is primarily concerned with

understanding the regulation of social behaviors and

the societal implications of stress effects. Their findings

have revealed a strong influence of stress in the

establishment of social hierarchies, social motivation

and aggressive behaviors, identified changes in the

dynamics of brain activity, and the expression of genes critically involved in neurotransmission among

the underlying mechanisms. Their work questions classical theories in the field of violence, which place

major emphasis on cultural influences and social learning, by implicating biological factors in the link

between early life stress and the emergence of violent individuals as well as the transgenerational

transmission of violence.

Prof. Carmen SANDILaboratory of Behavioral Genetics

lgc.epfl.ch

Vice Presidency of Academic Affairs StructureHTTP.//VPAA.EPFL.CH

School of Architecture, Civil and Environmental Engineering ENAC.EPFL.CH Dean: Prof. Marc Parlange

School of Basic Sciences SB.EPFL.CHDean: Prof. Thomas Rizzo

School of Computer and Communication Sciences IC.EPFL.CHDean: Prof. Martin Vetterli

School of Engineering STI.EPFL.CHDean: Prof. Demetri Psaltis

School of Life Sciences SV.EPFL.CHDean: Prof. Didier Trono

College of Management Technology CDM.EPFL.CH

College of Humanities CDH.EPFL.CH

Copyright VPAA, Research Affairs

Project VPAA, Research Affairs

Design VPAA, Research Affairs

Printing Reprographie EPFL

Available online http://DAR.epfl.ch