2007/12/04

The real value of a scientist's wage

Published online 28 November 2007 Nature 450, 597 (2007) doi:10.1038/450597a
News


Graphic Detail: The real value of a scientist's wage
Researchers' spending power is not what it seems.


Quirin Schiermeier


If money is the measure of all things, Austria may be the most attractive country in Europe for a working scientist. And India is close to Europe's leading science nations, even though the average gross salary for researchers there is a meagre €9,200 (US$13,600). That's according to data comparing scientists' salaries, after taking into account the cost of living (See Graphic detail).

The European Commission report includes data on the 2006 salaries of thousands of scientists working in the public and private sectors across 38 countries. The information was gathered from an online survey as well as from national databases.
The cost-of-living figures show that only Austria, Switzerland, the Netherlands, Luxembourg and Israel offer salaries similar to those in the United States, Australia and Japan.
Unweighted, Switzerland (€82,700) has the highest gross salary worldwide. Bulgaria (€3,600) and China (€3,200) have the lowest salaried scientists of the countries in the study.
There are striking differences within the member countries of the European Union (EU). On average, EU researchers can expect €22,500 less than their colleagues in the United States, Japan and Australia — after the cost of living is factored in. “This huge disparity certainly contributes to our top people seeing better opportunities elsewhere in the world,” warns EU research commissioner Janez Potočnik, who announced the results on 13 November.

2007/11/29

Integrability, Stability, and Adiabaticity in Nonlinear Stimulated Raman Adiabatic Passage (Phys. Rev. Lett.) - A.P. Itin et al.

Phys. Rev. Lett. 99, 223903 (2007)

Integrability, Stability, and Adiabaticity in Nonlinear Stimulated Raman Adiabatic Passage

A. P. Itin1,2 and S. Watanabe1
1University of Electro-Communications, 1-5-1, Chofu-ga-oka, Chofu-shi, Tokyo 182-8585, Japan
2Space Research Institute, RAS, Profsoyuznaya str. 84/32, 117997 Moscow, Russia
(Received 22 March 2007; published 28 November 2007)


We study the dynamics of a two-color photoassociation of atoms into diatomic molecules via nonlinear stimulated Raman adiabatic passage process. The system has a famous counterpart in (linear) quantum mechanics, and has been discussed recently in the context of generalizing the quantum adiabatic theorem to nonlinear systems. Here we use another approach to study adiabaticity and stability in the system: we apply methods of classical Hamiltonian dynamics. We find nonlinear dynamical instabilities, cases of complete integrability, and improved conditions of adiabaticity.

©2007 The American Physical Society
URL: http://link.aps.org/abstract/PRL/v99/e223903
doi:10.1103/PhysRevLett.99.223903
PACS: 42.65.Dr, 02.30.Hq, 03.75.Mn, 05.30.Jp

2007/09/06

Colloquium: Coherently controlled adiabatic passage (Rev. Mod. Phys) - Petr Král et al.

Rev. Mod. Phys. 79, 53 (2007) (25 pages)

Colloquium: Coherently controlled adiabatic passage
Petr Král

Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, USA
Ioannis Thanopulos

Department of Chemistry, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
Moshe Shapiro

Departments of Chemistry and Physics, The University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1 and Department of Chemical Physics, The Weizmann Institute of Science, Rehovot 76100, Israel
(Published 2 January 2007)

The merging of coherent control (CC) and adiabatic passage (AP) and the type of problems that can be solved using the resulting coherently controlled adiabatic passage (CCAP) method are discussed. The discussion starts with the essence of CC as the guiding of a quantum system to arrive at a given final state via a number of different quantum pathways. The guiding is done by “tailor-made” external laser fields. Selectivity in a host of physical and chemical processes is shown to be achieved by controlling the interference between such quantum pathways. The AP process is then discussed, in which a system is navigated adiabatically along a single quantum pathway, resulting in a complete population transfer between two energy eigenstates. The merging of the two techniques (CCAP) is shown to achieve both selectivity and completeness. Application of CCAP to the solution of the nondegenerate quantum control problem is first discussed and shown that it is possible to completely transfer population from an initial wave packet of arbitrary shape, composed of a set of nondegenerate energy eigenstates, to a final arbitrary wave packet, also composed of nondegenerate states. The treatment is then extended to systems with degenerate states and shown how to induce isomerization between the broken-symmetry local minima of a Jahn-Teller Al3O molecule. These approaches can be further generalized to situations with many initial, intermediate, and final states and applied to quantum coding and decoding problems. CCAP is then applied to cyclic population transfer (CPT), induced by coupling three states of a chiral molecule in a cyclic fashion, 1231. Interference between two adiabatic pathways in CPT allows for a complete population transfer, coupled with multichannel selectivity, by virtue of its phase sensitivity. CPT can be used to show the purification of mixtures of right-handed and left-handed chiral molecules. Finally, quantum-field coherent control is introduced, where CCAP is extended to the use of nonclassical light. This emerging field may be used to generate new types of entangled radiation-matter states.

©2007 The American Physical Society

URL: http://link.aps.org/abstract/RMP/v79/p53

doi:10.1103/RevModPhys.79.53

PACS: 32.80.Qk, 33.80.-b, 42.50.Hz

2007/06/28

Quantum-state-selective two-photon excitation of multilevel systems assisted by the Stark shift (Phys. Rev. A) - Bo Y. Chang et al.

Phys. Rev. A 75, 063405 (2007) (10 pages)

Quantum-state-selective two-photon excitation of multilevel systems assisted by the Stark shift

Bo Y. Chang
College of Environmental Science and Applied Chemistry (BK21), Kyung-Hee University, Gyeonggi-do 449-701, Republic of Korea

Hyeonho Choi and Seokmin Shin
School of Chemistry, Seoul National University, Seoul 151-747, Korea

Ignacio R. Sola
Departamento de Quimica Fisica, Universidad Complutense, 28040 Madrid, Spain

(Received 28 October 2006; revised 18 March 2007; published 6 June 2007)

Stark-chirped rapid adiabatic passage [T. Rickes et al., J. Chem. Phys. 113, 534 (2000); A. A. Rangelov et al. Phys. Rev. A 72, 053403 (2005)] has been proposed as a laser scheme that allows the optical excitation of atoms or molecules with high quantum yields. The laser control proceeds via adiabatic passage assisted by dynamic Stark shifts. We propose several extensions of the scheme with alternative sequences, by frequency tuning or by repeating the pulse sequences, in order to achieve fine state selectivity within multilevel structures and adiabatic passage of quantum superposition states. The efficiency and selectivity of the schemes is compared with that achieved by other optical coherent methods.

©2007 The American Physical Society

URL: http://link.aps.org/abstract/PRA/v75/e063405
doi:10.1103/PhysRevA.75.063405
PACS: 32.80.Qk, 33.80.Be, 42.50.Hz

2007/05/19

Dynamic Stark Control of Photochemical Processes (Science) - Benjamin J. Sussman

Reports

Dynamic Stark Control of Photochemical Processes

Benjamin J. Sussman,1,2 Dave Townsend,1 Misha Yu. Ivanov,1 Albert Stolow1,2*

A method is presented for controlling the outcome of photochemical reactions by using the dynamic Stark effect due to a strong, nonresonant infrared field. The application of a precisely timed infrared laser pulse reversibly modifies potential energy barriers during a chemical reaction without inducing any real electronic transitions. Dynamic Stark control (DSC) is experimentally demonstrated for a nonadiabatic photochemical reaction, showing substantial modification of reaction channel probabilities in the dissociation of IBr. The DSC process is nonperturbative and insensitive to laser frequency and affects all polarizable molecules, suggesting broad applicability.

1 Steacie Institute for Molecular Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada.
2 Department of Physics, Queen's University, Kingston, Ontario K7L 3N6, Canada.

* To whom correspondence should be addressed. E-mail: albert.stolow@nrc.ca