PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Viewing macro behaviors of ultra-cold quantum gases through the micro-world

In a recent study published in Science researchers have been able to observed, for the first time, the collective spin dynamics of ultra-cold fermions with large spins

2014-01-13
(Press-News.org) Contact information: Alina Hirschmann
alina.hirschmann@icfo.es
34-935-542-246
ICFO-The Institute of Photonic Sciences
Viewing macro behaviors of ultra-cold quantum gases through the micro-world In a recent study published in Science researchers have been able to observed, for the first time, the collective spin dynamics of ultra-cold fermions with large spins Understanding collective behavior of ultra-cold quantum gases is of great interest since it is intimately related to many encountered systems in nature such as human behavior, swarms of birds, traffic jam, sand dunes, neutron stars, fundamental magnetic properties of solids, or even super-fluidity or super-conductivity. In all of these everyday life examples, collective behavior plays a crucial role since all participating objects move, voluntarily or not, synchronously.

In a recent study coordinated by the Institute of Laser Physics, University of Hamburg - Germany, in collaboration with ICFO – the Institute of Photonic Sciences, researchers have observed, for the first time, the collective spin dynamics of ultra-cold fermions by analyzing the microscopic properties of the particles through their local collisions. The researchers were able to observe that at very low temperatures, close to absolute zero, the individual properties of each particle team up and behave coherently as a single identity in spin space. The results obtained from this study have recently been published in Science.

The "super" behavior of matter is actually a macro manifestation of the micro-laws of quantum mechanics. In the quantum micro-world, particles are divided into two main groups: bosons (e.g. photons) and fermions (e.g. constituents of matter such as electrons, protons, neutrons). The difference between these particles is basically their spin: bosons have integer spins and fermions have half-integer spins. Bosons behave collectively in spin rotation since they like to bundle up as friends and go with the flow. In the case of fermions, scientists did not know, up to now, whether these particles could behave the same way since they apparently are loners in this world.

Even more, if an atomic gas is cooled down to extremely low temperatures, bosons present the characteristics that many of them can occupy the same quantum state – they constitute a Bose condensate. In contrast, fermions have the particular characteristic of having only one particle per single state occupied, according to Pauli's exclusion principle.

To obtain ultra-cold fermions, the researchers trapped, via the use of a laser light, a quantum degenerate gas containing potassium atoms, cooled it down to very low temperatures and prepared different spin mixtures at very low magnetic fields to induce spin-changing dynamics. They were able to observe that when particles with very high spins collide between each other in local interactions, the resulting individual spins change. However, as a whole, they behave in a collective manner stabilizing the gas through long-lived, large-amplitude spin oscillations.

Hence, the research group led by ICREA Professor at ICFO Dr. Maciej Lewenstein came up with a novel effective theory that could explain correctly the experiment and discovered that the collective behavior is a quantum phenomenon which is very sensitive to perturbations (e.g. the effect completely disappears with a very slight change in the temperature). As Maciej Lewenstein states, "Fermions, due to Pauli's principle, are "individualists" - they do not like to behave in a same way. Nevertheless, here they team up to exhibit amazingly robust collective behavior. "

Through the controlled interplay of different fundamental processes that either stimulate or suppress the collective behavior, scientists are being able to have an in-depth understanding of the model system at work and therefore seek new pathways to study yet inaccessible exotic phenomena such as the creation of topological structures and textures in degenerate quantum gases with high spin or future applications such as quantum sensors for the smallest magnetic fields possible.

### Reference: J. S. Krauser, U. Ebling, N. Fläschner, J. Heinze, K. Sengstock, M. Lewenstein, A. Eckardt, C. Becker, Giant Spin Oscillations in an Ultracold Fermi Sea, Science 10 January 2014: Vol. 343 no. 6167 pp. 157-160, DOI: 10.1126/science.1244059

About ICFO

ICFO-The Institute of Photonic Sciences was created in 2002 by the government of Catalonia and the Technical University of Catalonia as a center of research excellence devoted to the science and technologies of light with a triple mission: to conduct frontier research, train the next generation of scientists and technologists, and provide knowledge and technology transfer. In recognition of research excellence, ICFO was granted the Severo Ochoa accreditation by the Ministry of Science and Innovation.

Research at ICFO targets the forefront of science and technology based on light with programs directed at applications in Health, Renewable Energies, Information Technologies, Security and Industrial processes, among others. The center currently hosts 300 professionals including researchers and PhD students, working in 60 laboratories. All research groups and facilities are located in a dedicated 14.000 m2 building situated in the Mediterranean Technology Park in the metropolitan area of Barcelona.

Researchers at ICFO publish in the most prestigious journals and collaborate with a wide range of companies around the world. The Client Liaison Program at ICFO, which includes members of a large number of local and international companies, aims to create synergies between ICFO and the industrial sector. The institute actively promotes the creation of spin-off companies by ICFO researchers. The institute participates in a large number of projects and international networks of excellence. Foundation Cellex finances the NEST program at ICFO which makes possible many ambitious frontier research projects.


ELSE PRESS RELEASES FROM THIS DATE:

Building 'belt' offers cheap, quick repair of earthquake damage

2014-01-13
Building 'belt' offers cheap, quick repair of earthquake damage Four years after the January 2010 earthquake, 145,000 people still remain homeless in Haiti. A cheap and simple technology to repair earthquake damaged buildings – developed at the University of Sheffield ...

Postpartum depression improves with time -- but for many women, depressive symptoms linger

2014-01-13
Postpartum depression improves with time -- but for many women, depressive symptoms linger Up to half of patients develop chronic depression, reports Harvard Review of Psychiatry Philadelphia, Pa. (January 13, 2014) – Research evidence shows that symptoms ...

Towards perfect control of light waves

2014-01-13
Towards perfect control of light waves Detector for the measurement of the waveforms of pulsed laser radiation This news release is available in German. Modern mode-locked lasers are capable of producing extremely short light flashes that ...

No nano-dust danger from facade paint

2014-01-13
No nano-dust danger from facade paint Research into the safety of nanoparticles Five Empa laboratories were involved in the EU «NanoHouse» project, along with four other European research institutes and four industrial ...

Shoulder replacement eases pain, improves motion in rheumatoid arthritis patients, Mayo Study finds

2014-01-13
Shoulder replacement eases pain, improves motion in rheumatoid arthritis patients, Mayo Study finds ROCHESTER, Minn. — Jan. 13, 2014 — Shoulder arthritis is a common problem for rheumatoid arthritis patients: pain and difficulty moving their arms can grow so severe that ...

Multiple myeloma study uncovers genetic diversity within tumors

2014-01-13
Multiple myeloma study uncovers genetic diversity within tumors Subpopulations of cells could have implications for treatment The most comprehensive genetic study to date of the blood cancer multiple myeloma has revealed that the genetic landscape ...

BU study: 1 question may gauge the severity of unhealthy drug and alcohol use

2014-01-13
BU study: 1 question may gauge the severity of unhealthy drug and alcohol use Primary care physicians seeking to determine whether a patient's drug or alcohol use is problematic often have to rely on lengthy questionnaires containing dozens of items with multiple ...

2 players produce destructive cascade of diabetic retinopathy

2014-01-13
2 players produce destructive cascade of diabetic retinopathy Augusta, Ga. - The retina can be bombarded by reactive oxygen species in diabetes, prompting events that destroy healthy blood vessels, form leaky new ones and ruin vision. Now ...

Heart attack survivors paint a complex picture of adhering to medicine

2014-01-13
Heart attack survivors paint a complex picture of adhering to medicine Heart attack survivors of different races and genders are about equally likely to be on medications that reduce the risk of another heart attack and other potentially life-threatening ...

Benefits of cognitive training can last 10 years in older adults

2014-01-13
Benefits of cognitive training can last 10 years in older adults INDIANAPOLIS -- Exercises meant to boost mental sharpness can benefit older adults as many as 10 years after they received the cognitive training, researchers said Monday. In a study published in the Journal ...

LAST 30 PRESS RELEASES:

Signs identified that precede sudden arrhythmic death syndrome in young people

Discovery of bacteria's defence against viruses becomes a piece of the puzzle against resistance

Pre-eclampsia is associated with earlier onset and higher incidence of cardiovascular risk factors

Warwick astronomers discover doomed pair of spiralling stars on our cosmic doorstep

Soil conditions significantly increase rainfall in world’s megastorm hotspots

NK cells complexed with bispecific antibody yield high response rates in patients with lymphoma

Planetary health diet and mediterranean diet associated with similar survival and sustainability benefits

Singapore launches national standard to validate antimicrobial disinfectant products

Molecular stool test could improve detection of tuberculosis in adults with HIV

Suspected fibrocartilaginous embolus in Asian small-clawed otter (Aonyx cinereus)

Enhancing heat transfer using the turbulent flow of viscoelastic fluids

Exercise as an anti-ageing intervention to avoid detrimental impact of mental fatigue

UMass Amherst Nursing Professor Emerita honored as ‘Living Legend’

New guidelines aim to improve cystic fibrosis screening

Picky eaters by day, buffet by night: Butterfly, moth diets sync to plant aromas

Pennington Biomedical’s Dr. Leanne Redman honored with the E. V. McCollum Award from the American Society for Nutrition

CCNY physicists uncover electronic interactions mediated via spin waves

Researchers’ 3D-printing formula may transform future of foam

Nurture more important than nature for robotic hand

Drug-delivering aptamers target leukemia stem cells for one-two knockout punch

New study finds that over 95% of sponsored influencer posts on Twitter were not disclosed

New sea grant report helps great lakes fish farmers navigate aquaculture regulations

Strain “trick” improves perovskite solar cells’ efficiency

How GPS helps older drivers stay on the roads

Estrogen and progesterone stimulate the body to make opioids

Dancing with the cells – how acoustically levitating a diamond led to a breakthrough in biotech automation

Machine learning helps construct an evolutionary timeline of bacteria

Cellular regulator of mRNA vaccine revealed... offering new therapeutic options

Animal behavioral diversity at risk in the face of declining biodiversity

Finding their way: GPS ignites independence in older adult drivers

[Press-News.org] Viewing macro behaviors of ultra-cold quantum gases through the micro-world
In a recent study published in Science researchers have been able to observed, for the first time, the collective spin dynamics of ultra-cold fermions with large spins