Free Republic
Browse · Search
News/Activism
Topics · Post Article

Skip to comments.

Stripped down spectroscopy to probe single molecules
Chemistry World ^ | 16 January 2012 | Kate McAlpine

Posted on 01/16/2012 10:20:22 PM PST by neverdem

Spectroscopy, a key method of identifying atoms and molecules with light, has been taken to its most fundamental level - a single photon absorbed by a single molecule. In addition to paving the way toward new experiments that observe the interaction between light and matter at its most basic level, the researchers that accomplished the feat suggest that their technique could also work with other photon-emitters, including those under study for quantum communication.

Spectroscopy works by finding the frequencies of light that will put an atom or molecule into an excited state - these comprise the chemical's unique absorption and emission spectrum. By using the organic dye dibenzanthanthrene (DBATT) as both the emitter and absorber molecule, the team at the Swiss Federal Institute of Technology, Zurich, ensured that the single-photon source and target would be on the same wavelength. They made both the photon emitter and target of DBATT embedded into a tetradecane matrix and cooled them to 1.5K. In the emitter, the molecules were so diffuse that the team could focus lasers on them one at a time, exciting it so that it produced a stream of single photons. 

Single photon spectroscopy
Single photon spectroscopy could help to develop optical computing

© Shutterstock

Collecting the single photons and funnelling them to the target molecule was 'one of the main challenges' of the experiment, according to Vahid Sandoghdar, who is now at the Max Planck Institute for the Science of Light in Erlangen, Germany. To accomplish this, the team surrounded the emitter with highly efficient lenses which allowed little light to escape, and these directed the photons into an optical fibre which took them to the target. They then took advantage of the fact that a molecule's absorption spectrum is influenced by its immediate environment in a matrix. By tweaking the frequencies of the incoming photons, the team could tune into a particular DBATT molecule like they would a radio station, and a matching set of lenses focused the light into the target. The team deduced the number of photons absorbed by the target molecule by monitoring the intensity of the single photon beam before and after it reached the target.

'It is an important contribution towards the controlled interaction of single photons and single quantum systems,' says Jürgen Eschner of the University of Saarland in Saarbrücken, Germany. He suggests that these interactions could have application in quantum communication or optical computing, in which single photon emitters and absorbers send and receive information. 'The transmission of a single photon is communication between the most fundamental physical entities - making their quantum properties accessible at the same time,' he says.

 

 

References

Y L ARezus et al, 2012, arXiv:1110.4255 [pre-print]

Also of interest

Ions in helium nanodroplets

Helium nanodroplets host ion analysis

28 September 2010

New infrared spectroscopy technique uses freezing helium to provide detailed structural information of molecular ions


Calculating hydrogen's molecular energy with quantum computers

Quantum computer hits hydrogen bullseye

15 January 2010

A basic quantum computer has successfully calculated hydrogen's molecular energy


Three-in-one spectroscopy

A way to monitor chemical reactions as they happen during catalysis has been developed.



TOPICS: Culture/Society; News/Current Events; Technical
KEYWORDS: chemistry; computing; physics; spectroscopy
Single-photon spectroscopy of a single molecule
1 posted on 01/16/2012 10:20:27 PM PST by neverdem
[ Post Reply | Private Reply | View Replies]

To: neverdem

Maybe now they can start Spectrographing nanos in general.
Wouldn’t it be loverley to know WTF (Winning the Future) is in nanos?


2 posted on 01/16/2012 11:00:43 PM PST by acapesket
[ Post Reply | Private Reply | To 1 | View Replies]

To: neverdem

Oh. I thought this was going to be an article about the TSA.


3 posted on 01/16/2012 11:27:12 PM PST by Jim Robinson (Rebellion is brewing!! Impeach the corrupt Marxist bastard!!)
[ Post Reply | Private Reply | To 1 | View Replies]

To: neverdem

Now I’m hungry


4 posted on 01/17/2012 12:25:46 AM PST by onona (FR is continuing education)
[ Post Reply | Private Reply | To 1 | View Replies]

To: neverdem

Very impressive.


5 posted on 01/17/2012 12:27:56 AM PST by TChad
[ Post Reply | Private Reply | To 1 | View Replies]

To: neverdem

Bookmarked for after coffee.... which is why I am not a Chemistry major.


6 posted on 01/17/2012 2:20:46 AM PST by momincombatboots (Back to West by G-d Virginia.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: El Gato; Ernest_at_the_Beach; Robert A. Cook, PE; lepton; LadyDoc; jb6; tiamat; PGalt; Dianna; ...
Synthetic Windpipe Is Used to Replace Cancerous One

New Storage Device Is Very Small, at 12 Atoms

Too Much Vitamin D Could Be Harmful to Heart

Scientists Shed New Light On Link Between 'Killer Cells' and Diabetes

FReepmail me if you want on or off my health and science ping list.

7 posted on 01/17/2012 7:14:39 AM PST by neverdem (Xin loi minh oi)
[ Post Reply | Private Reply | To 1 | View Replies]

To: El Gato; Ernest_at_the_Beach; Robert A. Cook, PE; lepton; LadyDoc; jb6; tiamat; PGalt; Dianna; ...
Synthetic Windpipe Is Used to Replace Cancerous One

New Storage Device Is Very Small, at 12 Atoms

Too Much Vitamin D Could Be Harmful to Heart

Scientists Shed New Light On Link Between 'Killer Cells' and Diabetes

FReepmail me if you want on or off my health and science ping list.

8 posted on 01/17/2012 7:15:29 AM PST by neverdem (Xin loi minh oi)
[ Post Reply | Private Reply | To 1 | View Replies]

To: El Gato; Ernest_at_the_Beach; Robert A. Cook, PE; lepton; LadyDoc; jb6; tiamat; PGalt; Dianna; ...
Synthetic Windpipe Is Used to Replace Cancerous One

New Storage Device Is Very Small, at 12 Atoms

Too Much Vitamin D Could Be Harmful to Heart

Scientists Shed New Light On Link Between 'Killer Cells' and Diabetes

FReepmail me if you want on or off my health and science ping list.

9 posted on 01/17/2012 7:15:50 AM PST by neverdem (Xin loi minh oi)
[ Post Reply | Private Reply | To 1 | View Replies]

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
News/Activism
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson