Navigation Links
Harvard University engineers demonstrate quantum cascade laser nanoantenna
Date:10/22/2007

Cambridge, Mass. October 22, 2007 In a major feat of nanotechnology engineering researchers from Harvard University have demonstrated a laser with a wide-range of potential applications in chemistry, biology and medicine. Called a quantum cascade (QC) laser nanoantenna, the device is capable of resolving the chemical composition of samples, such as the interior of a cell, with unprecedented detail.

Spearheaded by graduate students Nanfang Yu, Ertugrul Cubukcu, and Federico Capasso, Robert L. Wallace Professor of Applied Physics, all of Harvards School of Engineering and Applied Sciences, the findings will be published as a cover feature of the October 22 issue of Applied Physics Letters. The researchers have also filed for U.S. patents covering this new class of photonic devices.

The lasers design consists of two gold rods separated by a nanometer gap (a device known as an optical antenna) built on the facet of a quantum cascade laser, which emits invisible light in the region of the spectrum where most molecules have their tell tale absorption fingerprints. The nanoantenna creates a light spot of nanometric size about fifty to hundred times smaller than the laser wavelength; the spot can be scanned across a specimen to provide chemical images of the surface with superior spatial resolution.

Theres currently a major push to develop powerful tabletop microscopes with spatial resolution much smaller than the wavelength that can provide images of materials, and in particular biological specimens, with chemical information on a nanometric scale, says Federico Capasso.

While infrared microscopes, based on the detection of molecular absorption fingerprints, are commercially available and widely used to map the chemical composition of materials, their spatial resolution is limited by the range of available light sources and optics to well above the wavelength. Likewise the so-called near field infrared microscopes, which rely on an ultra sharp metallic tip scanned across the sample surface at nanometric distances, can provide ultrahigh spatial resolution but applications are so far strongly limited by the use of bulky lasers with very limited tunability and wavelength coverage.

By combining Quantum Cascade Lasers with optical antenna nanotechnology we have created for the first time an extremely compact device that will enable the realization of new ultrahigh spatial resolution microscopes for chemical imaging on a nanometric scale of a wide range of materials and biological specimens, says Capasso.

Quantum cascade (QC) lasers were invented and first demonstrated by Capasso and his group at Bell Labs in 1994. These compact millimeter length semiconductor lasers, which are now commercially available, are made by stacking nanometer thick layers of semiconductor materials on top of each other. By varying the thickness of the layers one can select the wavelength of the QC laser across essentially the entire infrared spectrum where molecules absorb, thus custom designing it for a specific application. In addition by suitable design the wavelength of a particular QCL can be made widely tunable. The range of applications of QC laser based chemical sensors is very broad, including pollution monitoring, chemical sensing, medical diagnostics such as breath analysis, and homeland security.


'/>"/>

Contact: Michael Patrick Rutter
mrutter@seas.harvard.edu
617-496-3815
Harvard University
Source:Eurekalert

Related biology technology :

1. Harvard advance improves stem cell research; not a medical revolution
2. GE Healthcare, Harvard medical school to collaborate on nervous system research
3. Fermentation Cell Culture: University Style
4. Fueling our economy with the University of Wisconsin
5. CIO Leadership Series: Ed Meachen, University of Wisconsin System
6. University, business leaders convene in Wausau
7. University of South Florida expands GE Healthcare relationship
8. State and university form network for entrepreneurial outreach
9. University center offers speed boost to manufacturers
10. Building the modern public-purpose university should be UW Systems goal
11. University Research Park to add 20 incubator suites
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/20/2017)... ... June 20, 2017 , ... ... the adulterants which pose the most likely threat to their products at the ... year. , IFT's annual food expo attracts over 20,000 attendees representing food ...
(Date:6/20/2017)... ... June 20, 2017 , ... National executive search ... with extensive assay development and biomarker expertise, as VP of Scientific Affairs at ... specializing in bio-analytical assay development and sample testing services. The organization acts as ...
(Date:6/20/2017)... ... June 20, 2017 , ... GigaGen Inc ., ... immune repertoires, announces launch of its new Surge(TM) Discovery service at ... of GigaGen, will present on Surge at the conference. , Surge is the ...
(Date:6/19/2017)... ... June 19, 2017 , ... EDETEK, Inc., ... today that it is launching two new additions of its award-winning cloud-based platform ... capabilities at the DIA 2017 Annual Meeting in Chicago, IL, June 19-22, 2017. ...
Breaking Biology Technology:
(Date:4/4/2017)... , April 4, 2017   EyeLock LLC , ... that the United States Patent and Trademark Office (USPTO) ... covers the linking of an iris image with a ... and represents the company,s 45 th issued patent. ... is very timely given the multi-modal biometric capabilities that ...
(Date:3/30/2017)... March 30, 2017 Trends, opportunities and forecast ... behavioral), by technology (fingerprint, AFIS, iris recognition, facial recognition, ... others), by end use industry (government and law enforcement, ... and banking, and others), and by region ( ... Asia Pacific , and the Rest ...
(Date:3/24/2017)... -- The Controller General of Immigration from Maldives Mr. ... have received the prestigious international IAIR Award for the most innovative high ... ... Maldives Immigration Controller ... (small picture on the right) have received the IAIR award for the ...
Breaking Biology News(10 mins):