Physical Science - Answer Key

CSIR NET -  Physical Science   Answer key for SET - A  (Comment your suggestions)

PART -  A

1. 3
2. 4
3. 4
4. 4
6. 1
8. 3
9. 3
11. 4
12. 2
13. 2
15. 2
16. 3
18. 3
19. 2
20. 1

PART - B

21. 1
22. 4
23. 2
24. 2
25. 1
26. 4
27. 4
28. 2
29. 3
30.
31. 1
32. 1
33. 3
34. 2
35. 4
36. 4
37. 4
38.
39. 2
40. 4
41.
42.
43.
44.
45.

 PART - C

46.
47. 4
48. 4
49. 4
50. 1
51. 3
52. 3
53. 4
54. 2
55. 1
56. 4
57. 2
58. 2
59.
60. 4
61. 1
62.
63. 3
64. 4
65. 4
66.
67. 3
68.
69. 1
70. 3
71. 4
72. 1
73.
74.
75. 1

Nobel Prize in Physics

The Nobel Prize in Physics 2013
François Englert, Peter Higgs

The Nobel Prize in Physics 2013

Photo: Pnicolet via Wikimedia Commons

François Englert

Photo: G-M Greuel via Wikimedia Commons

Peter W. Higgs

The Nobel Prize in Physics 2013 was awarded jointly to François Englert and Peter W. Higgs "for the theoretical discovery of a mechanism that contributes to our understanding of the origin of mass of subatomic particles, and which recently was confirmed through the discovery of the predicted fundamental particle, by the ATLAS and CMS experiments at CERN's Large Hadron Collider"

JEST-2014

JEST-2014

Important Dates

• JEST 2014 is schedule to be held on 16th February 2014
• Online (ONLY) Application start from 11th Nov 2013
• Last date for online applications 10th Dec 2013

GS-2014

Tata Institute of Fundamental Research
(Deemed University)

Graduate School Admissions (GS-2014)

 

TIFR Nationwide Entrance Examination will be held on Sunday, December 8, 2013. Online application link will be made active on September 3, 2013 at 11:00 a.m.

GATE-2014

GATE 2014     Conducted by IIT Kharagpur.

Important Dates

Csir-Net Answer Key

CSIR NET Answer key published.  Click here to download(Physical Science Only).

Physical Sciences        Key

Twisted light transmits more data

Spiral beams allow multiple information streams in one cable

A new fiber-optic cable that seamlessly shuttles multiple beams of light simultaneously could drastically speed data transfer over the Internet.

“It’s like having more fibers without actually laying more fibers,” says Andrew Weiner, a physicist at Purdue University in West Lafayette, Indiana.

Voyager 1 on fast track toward interstellar space

                                 

More than 35 years after launch, the probe finally nears the solar system's edge.  Voyager 1 is illustrated merging onto the "magnetic highway" at the solar system's edge.

JPL-Caltech/NASA

The Voyager 1 space probe has merged into a newly discovered zone at the solar system’s edge, and scientists think the craft’s next destination could be interstellar space. Measurements from Voyager’s erratic transition, presented at a meeting in December (SN: 1/12/13, p. 17) and in the June 27 Science, reveal  that the probe no longer encounters particles emanating from the sun. But Voyager 1 still feels the effects of the sun’s spiral magnetic field. Voyager team scientists think this realm could represent the last leg of Voyager’s journey out of the solar system.

A change in the orientation of the magnetic field will likely herald the probe’s entry into interstellar space. When this will happen “is anybody’s guess,” says  Leonard Burlaga, a Voyager team member at NASA’s Goddard Space Flight Center in Greenbelt, Md. But the timing of another Voyager milestone is certain: The plutonium that powers the spacecraft’s instruments will run out in 2020. The team hopes the probe will escape the solar system before then, Burlaga says. “We're looking forward to seeing that interstellar medium.”

Csir - jun 2013 detailed answers click the link below

Csir - jun 2013 Detailed answers 

   Above link will  provide some of the questions with detailed answers for csir net jun 2013 (physical science only) .  This answer sheet will be expanded soon for other questions.  Stay in touch.

with regards.

CSIR-NET 2013 Question Papers

Joint CSIR UGC NET Exam Question Papers
Exam Date	Subject	Answer Keys
June 2013	Chemical Sciences  Earth Sciences  Life Sciences  Mathematical Sciences  Physical Sciences  Engineering Sciences	Key for June 2013 JRF/NET exam  question papers will be uploaded  in the first week of July 2013

Hubble finds hints of a planet oddly far-flung from its star

If confirmed, the dark gap in space debris will challenge astronomers' theories

 

A dark ring appears about halfway through the dusty disk surrounding the star TW Hydrae in this Hubble Space Telescope image. A planet may have swept away debris, creating the gap.

NASA, ESA, J. Debes/STScI, H. Jang-Condell/Univ. of Wyoming, A. Weinberger/Carnegie Inst. of Washington, A. Roberge/GSFC, G. Schneider/Univ. of Arizona, A. Feild/STScI

A mysterious gap in a star’s dusty shell of debris could be the signature of a young planet circling its sun at twice the distance of Pluto’s orbit. If it does exist, the far-flung planet’s birth may be hard for astronomers to explain.

Light breaks up to cloak gaps in time

Method could hide messages without sender's knowledge

A device that manipulates light to open up small gaps in time has crept toward implementation outside the lab. Detailed June 5 in Nature, it could soon improve security over fiber-optic lines or improve data streaming rates.

“It’s exciting to see this exotic manipulation of light and its applications for communications and data processing,” says Alexander Gaeta, a Cornell University physicist who demonstrated the first time cloak two years ago (SN: 8/13/11, p. 12).

The term “cloak” can bring to mind Harry Potter-esque materials that hide an object at a specific point in space. These cloaks, a hot area of research since they were proposed in 2006, manipulate light so that an observer cannot see a stationary object.

Mars trip would deliver big radiation dose

Curiosity instrument confirms expectation of major exposures

The Mars Science Laboratory spacecraft (illustrated) carried the Curiosity rover to Mars. The rover has an instrument that was able to measure radiation levels on the months-long flight.

Black hole mysteries

Scientists are just getting to know the black holes that help anchor our cosmos

 

Hungry black hole

Though black holes are invisible, they can create brilliant light shows. This illustration shows a black hole devouring a star.

The first rule for anyone dealing with a black hole is, of course, don’t get too close. But say you do. Then you’re in for quite a trip — a one-way trip — because there is no coming back once you fall into a black hole.
A black hole isn’t actually a hole. If anything, it’s the opposite. A black hole is a place in space containing a lot of stuff packed very closely together. It has accumulated so much mass — and therefore gravity — that nothing can escape it, not even light. And if light cannot escape a black hole, then neither can you.

Luckily, you don’t have to fall into a black hole to learn about this cosmic phenomenon. Decades of study from a safe distance have taught scientists quite a lot. Those observations, including startling discoveries made in recent months, continue to add to our understanding of how black holes help shape the universe.

Entrance exam CSIR-NET

NOTIFICATION
JOINT CSIR-UGC TEST FOR JRF/LS (NET) SCHEDULED ON 23.06.2013

It is informed to candidates who have applied for Joint CSIR-UGC test for JRF/LS (NET) scheduled on 23rd June, 2013 that the list of candidates registered for the test shall be available on CSIR, HRDG website www.csirhrdg.res.in from 23rd May, 2013 onwards. The candidates may check their registration at the above said website, if any candidate whose name is not found registered, then he/she may contact the Examination Unit between 23rd to 29th May, 2013 alongwith (i) Both side photo copy of filled in application form/hard copy (in case of Online application) (ii) Proof of dispatch/an undertaking that he/she has submitted the application form within the stipulated closing date. In this regard, no request/representation will be entertained after 29.05.2013.

Physics

Nanostructures Put a Spin on Light

Y. Gorodetski et al., Phys. Rev. Lett. (2013)

Generating Far-Field Orbital Angular Momenta from Near-Field Optical Chirality

Yuri Gorodetski, Aurélien Drezet, Cyriaque Genet, and Thomas W. Ebbesen

Phys. Rev. Lett. 110, 203906 (2013)

Published May 16, 2013

Physics

Condensate in a Can

A. Gaunt et al., Phys. Rev. Lett. (2013)

Bose-Einstein Condensation of Atoms in a Uniform Potential

Alexander L. Gaunt, Tobias F. Schmidutz, Igor Gotlibovych, Robert P. Smith, and Zoran Hadzibabic

Phys. Rev. Lett. 110, 200406 (2013)

Published May 16, 2013

Physics

Wireless Power for Tiny Medical Devices

Published May 17, 2013  |  Physics 6, 57 (2013)  |  DOI: 10.1103/Physics.6.57

A new technique for powering medical implants wirelessly could allow them to shrink to sub-millimeter sizes in the future, according to theory and simulations.

Midfield Wireless Powering of Subwavelength Autonomous Devices

Sanghoek Kim, John S. Ho, and Ada S. Y. Poon

Phys. Rev. Lett. 110, 203905 (2013)

Published May 17, 2013

+Enlarge image

L. Monfils via Wikimedia Commons

Keeps on ticking. Electronic pacemakers like this one might be smaller and battery-free, according to simulations that demonstrate a wireless way to power small implanted devices.

+Enlarge image

A. S. Y. Poon/Stanford Univ.

Penetrating rays. A source of electromagnetic waves at the top of the image (not shown) can generate “hot spots” of field strength (ellipsoids) deep inside simulated biological tissue that are strong enough to power a pacemaker; according to computer simulations.

Medical electronic implants could be powered wirelessly, without the need for batteries or bulky receiver coils, if an approach described in Physical Review Letters pays off. The researchers propose a new design to allow wireless power transfer to even sub-millimeter-sized devices and show that in theory it should deliver enough power to drive a pacemaker.

Physics

Pool of Candidate Spin Liquids Grows

Courtesy L. Clark/University of Edinburgh

Gapless Spin Liquid Ground State in the S=1/2 Vanadium Oxyfluoride Kagome Antiferromagnet [NH₄]₂[C₇H₁₄N][V₇O₆F₁₈]

L. Clark, J. C. Orain, F. Bert, M. A. De Vries, F. H. Aidoudi, R. E. Morris, P. Lightfoot, J. S. Lord, M. T. F. Telling, P. Bonville, J. P. Attfield, P. Mendels, and A. Harrison

Phys. Rev. Lett. 110, 207208 (2013)

Published May 16, 2013

Physics

A New Look at the Hydrogen Wave Function

Christopher T. L. Smeenk, Joint Attosecond Science Laboratory, University of Ottawa and National Research Council of Canada, Ontario K1A 0R6, Canada

Published May 20, 2013  |  Physics 6, 58 (2013)  |  DOI: 10.1103/Physics.6.58

A newly-developed “quantum microscope” uses photoionization and an electrostatic magnifying lens to directly observe the electron orbitals of an excited hydrogen atom.

Hydrogen Atoms under Magnification: Direct Observation of the Nodal Structure of Stark States

A. S. Stodolna, A. Rouzée, F. Lépine, S. Cohen, F. Robicheaux, A. Gijsbertsen, J. H. Jungmann, C. Bordas, and M. J. J. Vrakking

Phys. Rev. Lett. 110, 213001 (2013)

Published May 20, 2013 | PDF (free)

+Enlarge image

APS/Alan Stonebraker

Figure 1 A photoionization microscope provides direct observation of the electron orbital of a hydrogen atom. The atom is placed in an electric field E and excited by laser pulses (shown in blue). The ionized electron can escape from the atom along direct and indirect trajectories with respect to the detector (shown on the far right). The phase difference between these trajectories leads to an interference pattern, which is magnified by an electrostatic lens.

Science

Avoiding ‘hot’ wheels

Teen designs device that could almost double the life of airplane tires

By Sid Perkins

Tire saver

Phillipe Lothaller, a 17-year-old South African, has invented a device that could save airlines big money by extending the life of tires.

Patrick Thornton, SSP

Nervous air travelers concerned about the risks of aging planes may first worry about how well the wings or engine are holding up. But a plane’s tires suffer a lot of wear and tear too. A new device that attaches to the wheel rims could extend the life of those tires, saving the world’s airlines millions of dollars per day. 

Visit the new Science News for Kids website and read the full story: Avoiding ‘hot’ wheels.

Physics

Kepler mission may be over

Multiple failures cripple planet-hunting telescope

By Andrew Grant

 

The telescope that has discovered thousands of exotic, quirky worlds — and a few tantalizingly Earthlike ones — orbiting distant stars is no longer capable of finding planets, at least temporarily and probably for good. Officials with NASA’s $600 million Kepler space telescope announced May 15 that an essential piece of hardware on the spacecraft has failed.

Since May 2009, Kepler has been staring at 170,000 stars and looking for tiny shadows cast by planets crossing in front of them. To enable Kepler to make such precise measurements, engineers installed four pointing devices, called reaction wheels, that turn the telescope and keep it dialed in on its stellar targets. One of the wheels stopped working last July, but the telescope requires only three.

Sunday Class Notes: Statistical Mechanics

Past sunday (12/05/2013)class notes available here, the topics are given below. To downloads the notes click on the topics
Ideal Fermi-Gas , Black body radiation, Specific heats of solids:

News : The Hindu

Sunday, science and success

• 
  Facilitating:H.S. Mani, Professor, Chennai Mathematical Institute, IMSc, at the Sunday science class.Photos: S. S. Kumar
• 
  Dr. S.V.M Sathyanarayana.

Dr. Satyanarayana has inspired many with his approach to learning and teaching.

Momeen Ummal who is now doing her post-doctoral research in Pittsburgh remembers the classes she used to attend in Chennai which helped her take the Graduate Aptitude Test in Engineering (GATE) exam. In 2003, she used to travel six kilometers to attend the class, but her teacher would come all the way from Kalpakkam. And that too without any fee or restriction on the students. These Sunday classes have helped many others…

Classical Mechanics problem Sheet

Classical Mechanics Problem Sheets-1(click here)


Hi friends.  Classical Mechanics problems sheet available here.  I collected all classical mechanics problems from various type of entrance exams.  You may download now and do these problems.  If you want to give any commend or want to ask any questions let me know. This problem sheet will be update....

Here,
Vaanka......

GATE - Answer key available in its own website

GATE 2013

GATE 2013 Question Paper and Answer Keys are available now

CSIR NET result published

NET result Published .... Check it's official website

Indian Institute of Technology, Indore

Indian Institute of Technology, Indore

 

PG/Ph.D Programme Admission-2013

IIT Indore invites applications from highly motivated and research oriented students for its following Full Time Regular PG and Ph.D Programmes

School of Basic Sciences

M.Sc/M.Sc + Ph.D Dual Degree

Chemistry: Minimum first Class (60% marks for General/OBC (55% for SC/ST) category in aggregate or as specified by the university/institute, or CPI/CGPA of 6.0 for Genera/OBC (5.5 for SC/ST) category on the scale of 10, with corresponding proportional requirements when the scales are other than on 10, or a first class as specified by the university/institute awarding the degree) bachelor’s degree with Chemistry as a subject for three years/six semesters and should have passed Mathematics at (10+2) level, and qualification in JAM-2013 in Chemistry

Particle caught flip-flopping

Particle caught flip-flopping

D meson’s switch between matter and antimatter could help uncover new particles

 

By Andrew Grant

A particle with an identity crisis could provide the next big discovery at the world's largest particle accelerator. The D meson has been caught in the act of flipping between matter and antimatter, researchers report online March 5 in Physical Review Letters.

D mesons, like other mesons, are short-lived particles that emerge from the shrapnel of proton collisions at CERN’s Large Hadron Collider outside Geneva. All of these particles decay within tiny fractions of a second. But four mesons, including the D, occasionally do something strange first: They become antiparticles. In the same vein, anti-D mesons can switch and become mesons before they decay. While experimenters have observed B, strange B and K mesons exhibit this shifty behavior, this is the first time physicists have seen D mesons that start as matter end up decaying as antimatter, and vice versa.

The next step, says Syracuse University physicist Steve Blusk, one of about 600 members of the team that made the discovery, is to compare the number of D meson decays with the number of anti-D meson decays. Those numbers should be equal, but physicists are hoping that one number is slightly larger than the other, Blusk says, because that would mean an undiscovered particle interferes with the D meson's oscillations.

Indian Institute of Science Education and Research, Mohali

Indian Institute of Science Education and Research, Mohali - Ph.D Admission

The Indian Institute of Science Education and Research invites applications for an interdisciplinary Ph.D in the Humanities and Social Sciences

Eligibility Criteria: M.A./MS/M.Phil/ B.Tech/B.Arch or equivalent degree in any subject with minimum 60% marks (or equivalent grade)

Selection Criteria: Please send email to hssphd@iisermohali.ac.in with the following; CV; a one page statement of Intent outlining research interests and previous experience; graduate transcripts, percentile in national level exams taken such as UGC NET, GATE; names and contact details of 3 referees

The shortlisted candidates will be required to appear for a research aptitude test and an interview at IISER, Mohali

The last date for submitting application for the August, 2013 session is 15th April, 2013

No vacancy around stars

No vacancy around stars 

 

Planets pack tightly in the Milky Way

By Andrew Grant

Planetary systems in our galaxy are packed to the brim, according to a new study — throw in another orb and all hell will break loose. The study, posted February 28 at arXiv.org, argues that planets around other stars share an evolutionary history similar to that of the solar system’s eight planets.

“This study supports results that have been building for a long time,” says Jack Lissauer, a space scientist at NASA Ames Research Center in Moffett Field, Calif., who was not involved in the study. In 2011, he discovered Kepler-11, a star with planets so tightly packed around it that five of them have smaller orbits than Mercury’s.

Chennai Mathematical Institute-PhD admission

Chennai Mathematical Institute B.Sc / M.Sc / Ph.D Admission 2013 

1. B.Sc (Hons) in Mathematics and Computer Science (3 year integrated course)

2. B.Sc (Hons) in Mathematics and Physics (3 year integrated course)

3. M.Sc: Mathematics, Applications of Mathematics, Computer Science

4. Ph.D: Mathematics, Computer Science, Physics

Eligibility

B.Sc (Hons) Mathematics and Computer Science: 12th standard or equivalent

B.Sc (Hons) Mathematics and Physics: 12th standard or equivalent

M.Sc (Mathematics): B.Sc (Math)/B.Math/B.Stat/B.E./B.Tech

M.Sc (Applications of Mathematics): B.Sc (Math, Physics, Statistics)/B.Math/B.Stat/B.E./B.Tech

M.Sc (Computer Science): B.E./B.Tech/B.Sc (C.S.)/BCA or B.Sc (Math) with a strong background in CS

Ph.D (Mathematics): B.E./B.Tech/B.Sc (Math)/M.Sc (Math)

Ph.D (Computer Science): B.E./B.Tech/M.Sc (C.S.)/MCA

Ph.D (Physics): B.E./B.Tech/B.Sc (Physics)/M.Sc (Physics)

Entrance Exam: For all the programmes, applicants will have to take an entrance examination on 15th May, 2013, Wednesday

Tweezers Work Well Under Pressure

Courtesy R. Bowman/University of Glasgow

Optical Trapping at Gigapascal Pressures

Richard W. Bowman, Graham M. Gibson, Miles J. Padgett, Filippo Saglimbeni, and Roberto Di Leonardo

Phys. Rev. Lett. 110, 095902 (2013)

Published February 28, 2013

Diamond anvil cells can apply millions of atmospheres of pressure to a solid or liquid, while allowing it to be observed through the diamond “windows.” For the first time, researchers have introduced optical tweezers into one of these cells in order to trap sample particles. The experiment, described in Physical Review Letters, directly measured the viscosity of the water surrounding the particles. Further development of this technique could permit investigations of the mechanical changes in biological cells and other soft materials placed under high pressure.

Star-Shaped Waves

J. Rajchenbach et al., Phys. Rev. Lett. (2013)

Observation of Star-Shaped Surface Gravity Waves

Jean Rajchenbach, Didier Clamond, and Alphonse Leroux

Phys. Rev. Lett. 110, 094502 (2013)

Published February 28, 2013

The ocean can produce exotic wave forms, such as “freak” waves, when normal waves combine in just the right way. These unusual wave patterns can—theoretically—take on a variety of different shapes, but researchers have so far only managed to produce a few distinct cases in the lab. As reported in Physical Review Letters, Jean Rajchenbach and colleagues at CNRS and the University of Nice in France have produced star- and polygon-shaped standing waves by vertically shaking a vessel filled with liquid oil.

Like Prefers Like, Except in a Virus

S. V. Venev and K. B. Zeldovich, Phys. Rev. Lett. (2012)

Segment Self-Repulsion is the Major Driving Force of Influenza Genome Packaging

Sergey V. Venev and Konstantin B. Zeldovich

Phys. Rev. Lett. 110, 098104 (2013)

Published February 28, 2013

Influenza and certain other viruses have a segmented genome, in which each segment is a strand of RNA that codes for a particular protein. New viruses forming from the many genome copies in an infected cell must amass one of each type of segment—and no duplicates—in order to go on to infect other cells and replicate. A better understanding of how segments recognize each other to form a complete genome could therefore lead to new antiviral drugs. In Physical Review Letters, Sergey Venev and Konstantin Zeldovich at the University of Massachusetts Medical School, Worcester, use a simple statistical model to predict the most efficient segment-signaling mechanism for avoiding duplicated genetic material.

Why the Solar Wind Blows Hot and Cold

Miloslav Druckmüller/Brno University of Technology, Peter Aniol, Vojtech Rusin

 

 

 

 

 

 

Sensitive Test for Ion-Cyclotron Resonant Heating in the Solar Wind

Justin C. Kasper, Bennett A. Maruca, Michael L. Stevens, and Arnaud Zaslavsky

Phys. Rev. Lett. 110, 091102 (2013)

Published February 28, 2013

One of the biggest puzzles of the solar wind is why certain ions in the wind are hotter than others. The temperature of helium ions, for example, is on average 5 times higher than that of hydrogen ions. Now, writing in Physical Review Letters, Justin Kasper of the Harvard-Smithsonian Center for Astrophysics, Massachusetts, and collaborators present a model that demonstrates how certain plasma waves, called ion cyclotron waves, will preferentially heat heavier ions travelling below a threshold velocity.

Rainbow Pattern May Allow Laser Damage Monitoring

Published March 1, 2013  |  Physics 6, 24 (2013)  |  DOI: 10.1103/Physics.6.24

Intense light pulses that can precisely sculpt solid materials also generate dazzling rainbow patterns that reveal information about the surface.

Ciliary White Light: Optical Aspect of Ultrashort Laser Ablation on Transparent Dielectrics

Yi Liu, Yohann Brelet, Zhanbing He, Linwei Yu, Sergey Mitryukovskiy, Aurélien Houard, Benjamin Forestier, Arnaud Couairon, and André Mysyrowicz

Phys. Rev. Lett. 110, 097601 (2013)

Published March 1, 2013

+Enlarge image

Y. Liu et al., Phys. Rev. Lett. (2013)

Not just a pretty face. This colorful pattern of light scattered from a solid surface being hit with laser pulses can convey details of the surface damage, such as the size of the laser-generated crater.

A spectacular sunburst of colored light produced as a laser beam bores into a solid surface could reveal information about the damage the light causes, according to a report in Physical Review Letters. The authors observed the rainbow pattern as they blasted a series of transparent materials such as glass and quartz with intense laser pulses. The team says that this effect, surprisingly overlooked until now, could offer a way of monitoring laser ablation, a technique used in fields as varied as dental surgery and art preservation.

Catch and Release of Photons

Antoine Browaeys, Laboratoire Charles Fabry, Institut d’Optique, CNRS, Université Paris Sud, 91127 Palaiseau, France

Published March 4, 2013  |  Physics 6, 25 (2013)  |  DOI: 10.1103/Physics.6.25

Two separate groups demonstrate the temporary storage and subsequent release of photons using very different quantum devices.

Catch and Release of Microwave Photon States

Yi Yin, Yu Chen, Daniel Sank, P. J. J. O’Malley, T. C. White, R. Barends, J. Kelly, Erik Lucero, Matteo Mariantoni, A. Megrant, C. Neill, A. Vainsencher, J. Wenner, Alexander N. Korotkov, A. N. Cleland, and John M. Martinis

Phys. Rev. Lett. 110, 107001 (2013)

Published March 4, 2013 | PDF (free)

Storage and Control of Optical Photons Using Rydberg Polaritons

D. Maxwell, D. J. Szwer, D. Paredes-Barato, H. Busche, J. D. Pritchard, A. Gauguet, K. J. Weatherill, M. P. A. Jones, and C. S. Adams

Phys. Rev. Lett. 110, 103001 (2013)

Published March 4, 2013 | PDF (free)

+Enlarge image

APS/Antoine Browaeys

Figure 1 In their experiment, Yin et al. tune the energy levels g and e in a superconducting circuit so that the transition frequency ν is resonant with the microwave cavity resonator. The resonator is connected to a transmission line with an adjustable coupling constant κ, which controls the release of microwave photons.

+Enlarge image

APS/Antoine Browaeys

Figure 2 In the experiment of Maxwell et al., the interface consists of an atomic cloud of rubidium atoms, whose states have a ladder configuration (shown on the right). The combination of a weak signal laser and control laser excites one atom (shown in red) into a Rydberg state r, while the other atoms remain in the ground state due to Rydberg blockade (see text). The researchers can couple this collective polariton state to another Rydberg state r′ using microwaves (MW).