Navigation Links
Lasers used to form 3-D crystals made of nanoparticles
Date:6/1/2011

ANN ARBOR, Mich.---University of Michigan physicists used the electric fields generated by intersecting laser beams to trap and manipulate thousands of microscopic plastic spheres, thereby creating 3-D arrays of optically induced crystals.

The technique could someday be used to analyze the structure of materials of biological interest, including bacteria, viruses and proteins, said U-M physicist Georg Raithel.

Raithel is co-author of a research paper on the topic published online May 31 in the journal Physical Review E. The other author is U-M research fellow Betty Slama-Eliau.

The standard method used to characterize biological molecules like proteins involves crystallizing them, then analyzing their structure by bombarding the crystals with X-rays, a technique called X-ray crystallography. But the method cannot be used on many of the proteins of highest interest---such as cell-membrane proteins---because there's no way to crystallize those molecules.

"So we came up with this idea that one could use, instead of a conventional crystal, an optically induced crystal in order to get the crystallization of a sample that could be suitable for structural analysis," said Raithel, professor of physics and associate chair of the department.

To move toward that goal, Raithel and his colleagues are developing the laser technique using microscopically small plastic spheres instead of the molecules. Other researchers have created 3-D optically induced crystals, but Raithel said the crystals his team created are denser than those previously achieved.

The process involves shining laser beams through two opposed microscope lenses, one directly beneath the other. Two infrared laser beams are directed through each lens, and they meet at a common focal point on a microscope slide that holds thousands of plastic nanoparticles suspended in a drop of water.

The intersecting laser beams create electric fields that vary in strength in a regular pattern that forms a 3-D grid called an optical lattice. The nanoparticles get sucked into regions of high electric-field strength, and thousands of them align to form optically induced crystals. The crystals are spherical in shape and about 5 microns in diameter. A micron is one millionth of a meter.

Imagine an egg crate containing hundreds of eggs. The cardboard structure of the crate is the optical lattice, and each of the eggs represents one of the nanoparticles. Stack several crates on top of each other and you get a 3-D crystal structure.

"The crate is the equivalent of the optical lattice that the laser beams make," Raithel said. "The structure of the crystal is determined by the egg carton, not by the eggs."

The optical crystals dissipate as soon as the laser is switched off.


'/>"/>

Contact: Jim Erickson
ericksn@umich.edu
734-647-1842
University of Michigan
Source:Eurekalert

Related biology technology :

1. Ultrafast lasers give CU-Boulder researchers a snapshot of electrons in action
2. Aerolase Reports Strong Sales in 2008 for Portable Aesthetic Lasers
3. Plasmonic whispering gallery microcavity paves the way to future nanolasers
4. Breaking barriers with nanoscale lasers
5. Scientists demonstrate multibeam, multi-functional lasers
6. Quantum leap for phonon lasers
7. Capasso lab demonstrates highly unidirectional whispering gallery microlasers
8. Engineers grow nanolasers on silicon, pave way for on-chip photonics
9. Better lasers for optical communications
10. New imaging technique reveals the atomic structure of nanocrystals
11. Physicists discover important step for making light crystals
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/20/2017)... YORK , January 20, 2017 ... Organization, cancer is one of leading causes of death ... 2012. Although the number of cancer related deaths increased ... 1990. Rising in incidence rate of various cancers continues ... to a research report by Global Market Insights, Inc. ...
(Date:1/19/2017)... Jan. 19, 2017  Market Research Future has a half cooked ... Liquid Biopsy is growing rapidly and expected to reach USD 450 ... Highlights ... Liquid Biopsy Market has been assessed as a swiftly growing market ... boom in the coming future. There has been a tremendous growth ...
(Date:1/19/2017)... Research and Markets ... the addition of the "Implantable Biomaterials Market Analysis ... report to their offering. Report Highlights: ... on current and future market trends to identify the investment opportunities ... base numbers Key market trends across the business segments, ...
(Date:1/19/2017)... GAITHERSBURG, Md. , Jan. 19, 2017 /PRNewswire/ ... a privately-held immunotherapeutics company targeting infectious diseases, announced ... the merger of PharmAthene and Altimmune in an ... Fund, HealthCap, Truffle Capital and Redmont Capital. The ... immunotherapeutics company with four clinical stage and one ...
Breaking Biology Technology:
(Date:1/6/2017)... NEWARK, Calif. , Jan. 5, 2017  Delta ... introduced its iris scanning technology for automotive at CESĀ® ... GNTX ) to demonstrate the use of ... to identify and authenticate the driver in a car, ... automobiles during the driving experience. Delta ID ...
(Date:12/22/2016)... NEW YORK , December 22, 2016 ... global provider of secure solutions for the e-Government, Public Safety, HealthCare, ... a subsidiary of SuperCom, has been selected to implement and deploy ... county in Northern California , further expanding its ... ...
(Date:12/16/2016)... 16, 2016 Research and Markets has announced ... Global Forecast to 2021" report to their offering. ... The biometric vehicle access ... a CAGR of 14.06% from 2016 to 2021. The market is ... to reach 854.8 Million by 2021. The growth of the biometric ...
Breaking Biology News(10 mins):