(December 13, 2010 – EurekAlert!) — A new laser-beam steering system that aims and focuses bursts of light onto single atoms for use in quantum computers has been demonstrated by collaborating researchers from Duke University and the University of Wisconsin-Madison.

Described in the journal Applied Physics Letters, published by the American Institute of Physics, the new system is somewhat like the laser-light-show projectors used at rock concerts and planetariums. But it’s much smaller, faster, atom-scale accurate and aimed at the future of computing, not entertainment.

In theory, quantum computers will be able to solve very complex and important problems if their basic elements, called qubits, remain in a special "quantum entangled" state for a long enough time for the calculations to be carried out before information is lost to natural fluctuations. One of several promising approaches to quantum computing uses arrays of individual atoms suspended by electromagnetic forces. Pulses of laser light manipulate the internal states of the atoms that represent the qubits, to carry out the calculation. However, the lasers must also be focused and aimed so accurately that light meant for one atom doesn’t affect its neighbors.

In the new system, tiny micromirrors, each twice the diameter of a human hair, pointed to each target atom in as little as 5 microseconds, which is about 1,000 times faster than sophisticated beam-steering mirrors developed for optical communications switching (units for light shows are slower). The researchers saw that the laser pulses also correctly manipulated the quantum properties of each target atom — in this case a line of five rubidium-87 atoms — without disturbing any neighboring atoms, which were separated by just 8.7 microns, about one-tenth the diameter of a human hair.

"Our experiments demonstrated the crucial requirement that our micromirror system maintain the laser-beam quality necessary to manipulate the internal states of the individual atoms," said Jungsang Kim, leader of the Duke researchers who designed the micromirror system. The atomic physics experiments were performed in Mark Saffman’s group at University of Wisconsin-Madison.

The groups plan to continue their collaboration, with future experiments targeting two-qubit gates, which are expected to be the basic building block of quantum logic, and atoms confined in larger two-dimensional arrays.

The article, "Independent individual addressing of multiple neutral atom qubits with a micromirror-based beam steering system" by Caleb Knoernschild, Xianli Zhang, Larry Isenhower, Alex T. Gill, Felix P. Lu, Mark Saffman, and Jungsang Kim appears in the journal Applied Physics Letters. See: http://link.aip.org/link/applab/v97/i13/p134101/s1

This work was funded by the Army Research Office, the Intelligence Advanced Research Projects Activity (IARPA), and the National Science Foundation.

Applied Physics Letters, published by the American Institute of Physics, features concise, up-to-date reports on significant new findings in applied physics. The American Institute of Physics is a federation of 10 physical science societies representing more than 135,000 scientists, engineers, and educators. Emphasizing rapid dissemination of key data and new physical insights, Applied Physics Letters offers prompt publication of new experimental and theoretical papers bearing on applications of physics phenomena to all branches of science, engineering, and modern technology. See: http://apl.aip.org/

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by Michael A. Fury, Techcet Group

December 9, 2010 – The second day of the IDTechEx combined Printed Electronics USA 2010 and Photovoltaics USA 2010 expanded from three parallel tracks to four, adding one degree of difficulty to covering the talks of interest. (Still, this was a cakewalk compared to covering an ECS or MRS meeting…I just wonder how long it will stay that way!)

Mike O’Reilly of Optomec described their ink atomizer system for printing inks up to 1000 cP viscosity and several microns thick, much more than can be done by inkjet. One application is a 3D stacked chip interconnect scheme that prints 10μm lines at a 30μm pitch. This sounds like the interconnect scheme developed by Vertical Circuits Inc., a Scotts Valley startup. The Optomec print nozzle delivers atomized ink focused by a shroud gas, so a 150μm nozzle can print 30μm traces that are 6μm tall.

Joshua Windmiller of UC San Diego talked about textile printed biosensors in the UCSD nanoengineering program. These flexible sensors are screen printed down to 100μm features on fabrics that contact the skin. Active elements include, for example, glucose oxidase in a graphite electrode on a Nafion film. Flexing the substrate exposes more active enzyme, thus enhancing the sensitivity of the sensor. The combined requirements of skin contact and flexing make the elastic waist band of underwear the obvious location for these sensors. Another example shown was a disposable wipe for high-sensitivity detection of explosives using a Gore-TEX substrate. These were not intended for use with underwear — the market consists of only one individual.

Heliovolt boasts the highest efficiency for CIGS PV at 11.5% peak, with a volume production average of >10%, noted company CEO Billy Stanbery. The material is the result of a CRADA (cooperative R&D agreement) with NREL, and is due to the exceptionally large grain size they are able to produce.

David Icke of MC10 has integrated off-the-shelf components with flexible substrates to product a class of stretchable electronics that are highly conformal. One application is a brain overlay sensor array that is 13-25μm thick. (Do not try this at home!) Other applications paper-based medical diagnostics and sensing devices.

Stan Farnsworth at NovaCentrix talked again this year about their Pulse Forge equipment that enables flash annealing of metals on plastic substrates without delamination or deformation. Tools have been shipped to labs and pilot lines, and products manufactured with the process will start to ship in 2011. In conjunction with their equipment, NovaCentrix developed a copper ink called Metalor, which is printed as copper oxide with a reducing agent. It is a screen printing paste that sells for $75/kg, making it an attractive alternative to silver paste. The reduced copper is mesoporous but still quite conductive.

Tony Killard of the Biomedical Diagnostics Institute at Dublin City University is developing a family of biosensors with screen printed materials with the intention of migrating them to inkjet systems. Demonstrated components include sensors for NH₃, urea, glucose, and cholesterol. The goal is to combine several sensors into what he calls a "smart integrated miniaturized sensor system" that includes heterogeneous integration of the sensors with a display, power, electronics and communications.

Erik Garnett of Stanford described their advanced nanostructured PV that combines Si and OPV into a single cell for greater conversion efficiency. The Si substrate is processed to form vertical Si nanowire arrays for light trapping; this surface exhibits absorption 70× greater than Si with conventional surface roughening. The gaps between the Si fingers are then filled with PEDOT for the OPV component. The vertical nanowire arrays are formed by coating the Si surface with a self-assembled monolayer of uniform SiO₂ spheres which act as a plasma etch mask. After Si etching, the SiO₂ is removed with HF, leaving the free-standing forest of Si pillars.

Davor Sutija of Thin Film Electronics showed a family of printed rewritable permanent memory devices using a ferroelectric polymer ink that was originally co-developed with Intel. The devices are fully R2R printable, with a single roll holding 3.6M memory devices with 20 bits each. It takes 50μsec and 20μC charge to set/reset the bits. The first commercial products are for games, in the form of their Toy Development Kit now available. In October 2010 they formed an alliance with PARC for 128-bit EPC memories with bipolar transistors. In 24-30 months they expect to have system products with 1000-5000 transistors.

Warren Jackson at HP is working on ZnSnO-channel transistors for R2R production on flexible substrates. The entire device film stack is blanket deposited on the roll, including a thick photoresist top layer. The thick resist is then patterned by a 3D roller stamp, which allows regions to selectively remove the layers down to the gate for contact. They are building 7×7cm display devices as a yield learning vehicle, using the eyeball as a rapid inexpensive tester.

Stephan Kirchmeyer at Heraeus Clevios (HC Stark Clevios GmbH) is using PEDOT-PSS as an ITO replacement for OPV, achieving 100Ω/square at 90% transparency. They are also working on materials for OLED that can serve as an ITO replacement for hole injection.

Shiv Chiruvolu of NanoGram talked about their 5-10nm Si particle inks, available in both n⁺ and p⁺. The different formulations can be applied by spin coating or screen printing. Inkjet is still in development, though already achieving 70μm lines at 100μm pitch. For TFT applications, they use low temperature laser sintering <180°C on a polycarbonate substrate. The company was acquired by Teijin in July 2010.

For the final stretch of the conference, all of the attendees were brought back to a single track. However, one room provided adequate capacity for the die-hards whereas the conference opening was 3× as large.

John Knight of PARC talked about fostering the PE product development infrastructure through their collaboration with Soligie. There is a gap between PE R&D and product realization/commercialization, which this alliance intends to bridge. There is also a gap between PE R&D and materials & process & equipment suppliers, which PARC intends to bridge. The objective of this PARC-Soligie alliance is to provide one stop shopping for PE product designers, a service that does not exist elsewhere.

Jani-Mikael Kuusisto of VTT Technical Research Center of Finland described their government-funded strategic initiative to foster R&D for product development and pilot production of several technologies, including PE. Successful programs include Orion Diagnostica and PrintoCent.

Peter Harrop of event organizer IDTechEx provided the last hurrah, looking forward to PE in 2010-2020. This market is expected to be $300B in <20 years. This is not unreasonable, considering that a good portion of PE will be directed toward consumer goods, itself a whopping $3T market. "The driver is to modernize print, not electronicsm," he said.

On both days of the conference, the schedule included an extended lunch break that allowed time for the exhibit floor, networking, and supplier seminars. This is a good arrangement that returns value to the supplier effort and expense of exhibiting.

The conference concluded on Dec.3 with five more short courses. The topics were:

• Displays and lighting

• Creating new products with PE

• Flexible substrates, transparent conductors, and barriers for flexible electronics

• RFID and its progress toward being printed

• Energy harvesting and storage for small electronic devices

Michael A. Fury, Ph.D, is senior technology analyst at Techcet Group, LLC, P.O. Box 29, Del Mar, CA 92014; e-mail [email protected].

(December 9, 2010) — Panasonic, core partner within imec’s Human++ program, and imec presented at the International Electron Devices Meeting (IEDM) in San Francisco various critical components of a biomedical lab-on-chip sensor enabling fast detection of Single Nucleotide Polymorphisms (SNPs) in DNA, such as a miniaturized pump for on-chip generation of high pressures, a micropillar filter optimized for DNA separation achieving record resolution, and a SNP detector allowing on-chip detection using very small sample volumes.

A SNP is a single nucleotide replacement in a DNA sequence that can result in different reaction by people to pathogens and medicines. Detection of these SNPs is increasingly important with the move towards more personalized healthcare.

Existing methods to detect SNPs require many sample processing steps in dedicated medical tools at medical laboratories. Such tests are labor-intensive, time-consuming and expensive. Moreover, large blood samples are needed. A lab-on-chip device can bring advantages to the patient and the healthcare system. Such devices enable fast, easy-to-use, cost-effective test methods which can be performed at regular times in a doctor’s office or even near the patient’s bed. This is very interesting for point-of-care applications such as personalized medicine.

By combining advanced micro-electronic fabrication processes with heterogeneous integration, imec and Panasonic aim to realize a state-of-the-art microfluidic device for SNP detection. In order to do this, advanced microfluidic components have been fabricated and optimized, such as a miniaturized pump for on-chip generation of high pressure, a micropillar filter optimized for DNA separation achieving world-record resolution, and a SNP detector allowing on-chip detection using very small sample volumes.

The entrance unit of the SNP detection system samples very small volumes of blood. This entrance unit features a miniaturized high-pressure pump based on an advanced conductive polymer actuator. After optimization, the actuator generates high pressures (up to 3MPa) at low voltage (~1.5V). The high pressure is essential to generate a fluid flow through the next unit of the SNP detection system. The on-chip low voltage operation is important because it opens the path to autonomy and portability of the lab-on-chip device.

Next, the DNA separation unit featuring an advanced micro-pillar array filter was developed. This deep-UV patterned silicon pillar array was realized using advanced MEMS technology. It consists of many micron-scale pillars, being typically 20µm high and with 1-2µm inter-pillar distance. The pillar array is used for DNA separation based on ion-pair reversed-phase (IR-RP) liquid chromatography. Imec and the VUB (Vrije Universiteit Brussel), a scientific partner of imec, optimized the pillar-based IR-RP liquid chromatography technique for DNA separation. This resulted in the first miniaturized on-chip system that enables fast and highly selective separation of short, double stranded DNA strands which only differ 50 base pairs in length. The resolution of the system is the highest in the world and proves the potential to handle 5 SNPs at the same time in the final SNP detection system.

The other functional units of the SNP detector are a unit for DNA extraction and polymerase chain reaction (PCR) using heaters and temperature sensors, and a SNP detection unit based on electrochemical sensors. The miniaturization of these sensors was of crucial importance, since the minimum required sensor volume determines the blood sampling volume needed for the SNP detection, and hence the dimensions of all components of the device. Scientists of Panasonic and imec demonstrated SNP detection capabilities using on-chip sensors handling a volume as small as 0.5µL.

Imec’s Human++ program provides a multidisciplinary R&D platform for industrial partners to collaborate on finding industry-relevant solutions for future healthcare and wellness needs by combining nanoelectronics and biotechnology into heterogeneous systems for diagnosis and therapy. Human++ partners build on imec’s 25 years of expertise in micro- and nanoelectronics and expertise in several healthcare-relevant domains.

More MEMS news from Panasonic and imec at IEDM here.

Imec performs world-leading research in nanoelectronics. Further information on imec can be found at www.imec.be.

Panasonic Corporation is a worldwide leader in the development and manufacture of electronic products for a wide range of consumer, business, and industrial needs.

The Vrije Universiteit Brussel (VUB) offers a quality education to more than 9000 students and hosts more than 150 research teams working on its campuses, and is one of the biggest centres of knowledge in the capital of Europe.

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