May 2012

White Paper

R&D Results – The Development of a High Accuracy Multipole Strip Magnet for Non-Contact Linear and Rotary Position Measurement

In global industry there is a need for the accurate, repeatable and reliable measurement of linear and rotary motion and position. This includes needs in the fields of ...

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Research & Development

Beyond the High-Speed Hard Drive: Topological Insulators Open a Path to Room-Temperature Spintronics  Berkeley Lab researchers and their colleagues demonstrate unique new materials for innovative electronic and magnetic applications 
Strange new materials experimentally identified just a few years ago are now driving research in condensed-matter physics around the world. First theorized and then discovered by researchers at the US Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) and their colleagues in other institutions, these strong 3-D topological insulators (TIs for short)  are seemingly mundane semiconductors with startling properties. For starters, picture a good insulator on the inside that's a good conductor on its surface, something like a copper-coated bowling ball.

A topological insulator's surface is not an ordinary metal, however. The direction and spin of the surface electrons are locked together and change in concert. And perhaps the most surprising prediction is that the surface electrons cannot be scattered by defects or other perturbations and thus meet little or no resistance as they travel. In the jargon, the surface states remain topologically protected - they can't scatter without breaking the rules of quantum mechanics.

"One way that electrons lose mobility is by scattering on phonons," said Alexis Fedorov, staff scientist for beamline 12.0.1 of Berkeley Lab's Advanced Light Source (ALS). Phonons are the quantized vibrational energy of crystalline materials, treated mathematically as particles. "Our recent work on a particularly promising topological insulator shows that its surface electrons hardly couple with phonons at all. So there's no impediment to developing this TI for spintronics and other applications."

The TI in question is bismuth selenide, Bi2Se3, on whose surface electrons can flow at room temperature, making it an attractive candidate for practical applications like spintronics devices, plus farther-out ones like quantum computers. Much of the research on electron-phonon coupling in Bi2Se3 was conducted at beamline 12.0.1 by a team including Fedorov, led by Tonica Valla of Brookhaven National Laboratory.

The right tool for the job

To study a TI's surface conductivity, electron transport on its surface has to be separated from total conductivity, including the poorly conducting bulk. One experimental technique, called angle-resolved photoemission spectrometry (ARPES), is adept at doing just this.

ARPES shines bright light, like that produced by the Advanced Light Source, on a sample and captures the electrons that the energetic photons knock free. By recording the angle and energy of these photoemitted electrons on a CCD detector, ARPES gradually builds up a direct graphic visualization of the sample's electronic structure.

"Of the several ARPES beamlines at the ALS, beamline 12.0.1 seems to have an ideal balance of energy, resolution, and flux for research on topological insulators," said Fedorov. "This beamline was used for some of the first experiments establishing that 3-D TIs actually occur in nature, and several teams have worked here validating the characteristics of TIs."

The photoemitted electrons in an ARPES experiment directly map out such features as the material's band structure - the energy difference, or gap, between electrons bound in atoms' outer shells, the valence band, and charge carriers that are free to rove, the conduction band. Insulators have wide band gaps, semiconductors have narrower ones.

The band structure of the surface states of a topological insulator like Bi2Se3 appear as two cones that meet at a point, called the Dirac point. There's no gap at all between the valence and conduction bands, only a smooth transition with increasing energy. This is similar to the band structure of the fascinating material graphene, a single sheet of carbon atoms, the thinnest possible surface. ARPES diagrams of band structures like these look like slices through the cones, an X centered on the Dirac point.

Although graphene and topological insulators have similar band structures, other electronic characteristics are very different. The combinations of different speeds and orientations equivalent to a material's highest particle energies (at zero degrees) make up its momentum space, mapped by the Fermi surface. While the Fermi surface of graphene lies between the conical bands at the Dirac point, this is not true of TIs. The Fermi surface of Bi2Se3 cuts high across the conical conduction band, mapping a perfect circle. It's as if the circular Fermi surface were drawn right on the surface of the topological insulator, showing how spin-locked surface electrons must change their spin orientation as they follow this continually curving path.

Values including electron-phonon coupling can be calculated from the diagrams that ARPES builds up. ARPES measures of Bi2Se3 show that coupling remains among the weakest ever reported for any material, even as the temperature approaches room temperature.

"Although there's still a long way to go, the experimental confirmation that electron-phonon coupling is very small underlines Bi2Se3's practical potential," said Fedorov. With continued progress, the spin-locked electronic states of room-temperature topological insulators could open a gateway for spintronic devices - and for more exotic possibilities as well.

For example, by layering a superconducting material onto the surface of a topological insulator, a feat recently achieved by a group of Chinese scientists working at beamline 12.0.1, it may be possible to create a theoretical but yet unseen particle that is its own antiparticle, one that could persist in the material undisturbed for long periods. Discovery of these so-called Majorana fermions would be an achievement in itself, and could also provide a way of overcoming the main obstacle to realizing a working quantum computer, a method of indefinitely storing data as "qubits."

The experimental examination of strong, 3-D topological insulators is a field hardly more than five years old, and the potential rewards, both for fundamental and applied science, have only begun to be explored.

Magnetics 2013: Call for Presentations

MEDER electronic, Inc. MMS - 2.8 mm Implantable MEMS Reed Sensors Need No Power

A new, ultra-small magnetically actuated reed sensor that requires no power and is designed for switching CMOS gates and other low power signal switching devices such as implantable medical pacemakers and insulin pumps is being introduced by MEDER electronic.

MEDER MMS Reed Sensors are magnetically actuated on/off sensors that feature no power draw and measure only 2.8 mm (L) [0.110”] by 2.05 mm (W) [0.080”] by 1.2 mm (H) [0.047"].  Designed for switching low power devices where size is critical, they are available with magnetic sensitivity ranges from 1 to 4 millitesla and are tested to withstand up to 15,000 G's shock from any direction.  Choose from 2 surface mount lead designs in a SPST-NO (Form A) version: lead design 1 (straight cut axial lead), and lead design 2 (Gull Wing).

Manufactured using semiconductor wafer technology, MEDER MMS Reed Sensors are supplied in tape and reel according to IEC 286/part 3, suitable for auto pick and place equipment. These SPST reed sensors have a switching voltage of 3 VDC max., with 109 insulation resistance across the contacts.  These reed sensors are EDS sensitive and RoHS compliant.  Available today at Digi-Key Corporation.

Nanotec Launches Stepper Motors with Magnetic 24 V Encoder And An Optional Brake
Nanotec Electronic, US, Inc. has introduced new models AS5918-EMN24 and AS5918-EMN24B, expanding its product portfolio by adding IP-rated stepper motors with an integrated, magnetic 24 V encoder and, on the EMN24B model, an integrated brake.

The two new AS5918-EMN24 and AS5918-EMN24B models from the renowned stepper motor manufacturer distinguish themselves chiefly with their magnetic 24V encoder. The encoder was developed by Nanotec for integration into IP-protected motors. Magnetic encoders are less sensitive to vibrations, dust, dirt and humidity. The encoder generates 1,024 increments per revolution. Because of the 24 V connection at the encoder, the motors are well-suited for direct control via a PLC or a higher-level control system. Of course, they can be controlled using Nanotec control systems as well.

The option with a safety brake (1 Nm of holding torque) is typically used wherever vertical loads have to be kept in place even during a power failure or an emergency stop in order to prevent damage to persons or property. This applies to Z-axes and other safety-critical applications.

Featuring a holding torque of 1.98 Nm, the AS5918-EMN24 and AS5918-EMN24B stepper motors are viable alternatives to servomotors with gearboxes in Torque Mode and Closed Loop at low speeds. This is because they are more compact and have greater energy efficiency - whether in mechanical engineering devices or other systems where operating in a harsh environment and precise positioning are crucial.

The motors have a high degree of electromagnetic compatibility and feature M12 and M8 connections. With a flange dimension of 56 mm (NEMA 23), they are compatible with all Nanotec stepper motors and thus can be used in mixed environments.

Cordless Magnetic Drill Press from Metabo Features Permanent Rare Earth Magnet
Metabo Corp. has introduced a cordless magnetic drill press. The MAG 28 LTX utilizes a 25.2 V Li-Ion battery to power the tool. A permanent rare earth magnet, requiring no energy from the battery, allows the use of the mag drill in remote and previously inaccessible environments.

The unique rare earth magnet offers up to 2,500 lbs of holding force, which can be adjusted for precise positioning when drilling on vertical, horizontal and sloped surfaces.  The drill has a prism-shaped magnetic base that enables users to work on pipe as well, further increasing the flexibility of this drill throughout steel construction applications.  A safety strap is supplied for working on overhead or vertical surfaces.

This first-to-market cordless electromagnetic drill press can be used with annular cutters, spiral drills and countersinks, featuring a maximum drilling diameter of 1.25 inches with an annular cutter and 0.5 inch with a spiral drill.  The tool offers a maximum drilling depth of 2 inches.

The tool's magnetic stand has a maximum stroke of 6.3125 inches.  The 2-speed tool boasts 380 or 680 no load revolutions per minute and is designed with a dual-level, permanently lubricated gearbox for speed and torque optimization. 

The MAG 28 LTX features electronic thermal overload protection and jam protection to help ensure the longevity of the 25.2 V motor.  A safety cut-out protects the operators in the event a battery is inserted with the machine in the on position. An integrated gravity coolant container with through-the-spindle coolant feed is also included.

The cordless tool's 25.2 V, 3.0 Ah Li-Ion battery pack charges in a 15 minute charger. Metabo's air-cooled charging technology cools the battery pack during charging to shorten the charging process by up to 30 percent, diminishing tool down-time and boosting useable tool life per charge.  A spare battery pack can also be stored in the drill's stand.  The battery packs and charger are further protected by a three-year warranty.  In addition, the MAG 28 LTX is warranted for three-years.

A Weldon 0.75-inch tool holder, ejector pin, chuck adaptor and geared chuck, chuck key, MT 2 drift key, safety strap, allen key and two 25.2 V, 3.0 Ah Li-Ion battery packs come standard with Metabo's MAG 28 LTX.

Infolytica Releases MagNet and ThermNet v7.3
Infolytica Corp. has released the newest versions of its simulation suite of software: MagNet, ElecNet, ThermNet and OptiNet.

Obtaining an accurate prediction of an electric motor’s performance is no trivial task, particularly when you wish to couple the effects of heating and motion. It can be tedious to setup these types of problems for simulation. MagNet and ThermNet share the same model file and run a two-way coupled electromagnetic and thermal simulation, making it both easy to use and accurate.

Several substantial updates have been made to ThermNet, increasing the software’s accuracy and capability to account for cooling options. Global results for temperature, heat capacity, heat flow and heat source are now reported. New boundary conditions, improved modeling of touching surfaces, anisotropic and composite materials, stranded coils and enhanced convection options work in tandem to improve the simulation of motors, generators or any other electromechanical device.

MagNet v7.3 introduces freezing the operating points of the BH property throughout a component for use in different simulations. One example of the application of this new feature is the study of small signals in the presence of a large DC offset.

Material properties can be overridden on an element by element basis in order to account for other phenomena or processes affecting the performance of a device. An example of this application is when the material properties of certain regions of a component vary due to a manufacturing process.

3D coil modeling, particular highly complex geometries, is made easier with an updated extension to MagNet which supports all common types of windings.

General improvements have also been made to third party file interoperability, specifically CATIA V5 and Inventor 2012, as well as the utility which detects and corrects faults with imported models.

MagNet, ElecNet ThermNet and OptiNet v7.3 can now be downloaded for PC’s running Microsoft Windows XP, Vista and 7.

New 14-Bit Magnetic Encoder from austriamicrosystems Makes Accurate Angle Measurement For Microcontroller Users
austriamicrosystems has released the AS5048, a 14-bit magnetic encoder IC offering new features that make it easier to achieve accurate, reliable angle measurements in microcontroller-based applications.

The AS5048, which provides a PWM output and either an SPI or I2C interface, supplies absolute angle measurements to a host microcontroller. The application’s mechanical design does not need to allow for precise initial alignment of the sensor IC and the two-pole magnet it is paired with: instead, the zero position is programmed into the AS5048 magnetic encoder one time only on assembly, via a simple SPI or I2C command, with no requirement for a special programming device.

The AS5048 is also highly tolerant of misalignment between the sensor IC and its paired magnet and of variations in the air gap, as well as of variations in temperature from -40°C to 150°C.

The new AS5048 magnetic rotary encoder offers more precise measurement than previous members of austriamicrosystems’ family of magnetic rotary encoders. Its 14-bit measurement engine provides for resolution down to 0.0219°. With linearization and averaging implemented in the host microcontroller, it can deliver angle measurements accurate to 0.05°.

The new AS5048 also takes advantage of proprietary manufacturing processes developed at austriamicrosystems’ wafer fab in Graz, Austria that enable the production of extremely sensitive analog circuits. The IC’s high sensitivity means that it can be paired with low-cost magnet types such as ferrites, operating reliably in magnetic fields as weak as 30 mT.

Like austriamicrosystems’ existing magnetic encoders, this new device rejects interference from stray magnetic fields, because of the unique design of the IC’s integrated Hall sensors and signal processing circuitry. This makes the AS5048 well suited for use in electrically and magnetically noisy industrial and medical environments.

An internal voltage regulator enables the AS5048 to operate from either a 3.3 V or 5 V supply. It is available in a 14-pin TSSOP package. Multiple devices can be daisy-chained to produce a serial data read-out.

“austriamicrosystems is a long-standing supplier of magnetic encoders to thousands of customers, and feedback from these customers on our existing devices has helped us to make the new AS5048 a very attractive product,” said Alfred Binder, marketing manager at austriamicrosystems. “It is accurate and robust like all of austriamicrosystems’ magnetic encoders, easy to assemble in an end product, and now even easier to implement in microcontroller-based designs.”

New Versatile FE-SEM Series for Sub-Nanometer Imaging and Analysis of Nanostructures and Magnetic Samples
JEOL has launched a new series of field emission scanning electron microscopes (FE-SEM) that offer expanded imaging and analysis capabilities customizable to performance requirements. The JEOL JSM-7100F series offers sub-1 nm imaging capabilities and analytical characterization at the sub-100 nm scale, accomplished through the combination of large beam currents with a small probe size at any accelerating voltage.

Designed for the budget-conscious lab, the JSM-7100F model is a versatile, analytical field emission SEM that offers a new level of expanded performance. Through the unique 'in-lens field emission gun', the SEM delivers ≥ 200 nA of beam current to the sample. An aperture angle control lens (ACL) automatically optimizes both small probe current spot size for high resolution imaging and spot shape for high beam current, high resolution microanalysis, while a beam deceleration mode curtails charging on nonconductive specimens such as ceramics, semiconductors and polymers. 

For advanced high resolution capabilities, the JSM-7100FT model features a newly redesigned hybrid lens and through-the lens detectors with energy filter. The improved electron optics design of this SEM column enables high resolution imaging of nanostructures and specimen surface details for any material type, including magnetic samples. With the integration of in-the-lens acceleration and deceleration of the electron beam, low kV aberrations are reduced, yielding higher resolution at the lowest accelerating voltages. Additionally, JEOL's proven beam deceleration mode (GB Mode) decreases charging while imaging non-conductive specimens, improves spot size at low kV, and enhances surface topography.

This new series of Field Emission SEMs offers increased versatility for multiple analytical techniques and imaging and analysis of non-conductive samples. Each microscope model features a turbo molecular pump (TMP) and a rapid specimen exchange airlock to assure a clean vacuum environment is always maintained. 

The optional LV function (up to 300 Pa) offers additional versatility to both JSM-7100F and JSM-7100FT. The LV function is fully controlled through the microscope user interface and allows all LV orifices to be retracted without breaking vacuum for unrestricted low magnification imaging and maximum beam current (200 nA) in high vacuum. The LV system is equipped with a solid-state BSE detector.

The JSM-7100F series is equipped with a large specimen chamber that accommodates a wide variety of detectors and accessories simultaneously and without compromising the performance of one another, including: multiple EDS, WDS, STEM, BSE, CL and IR camera. The system can also be equipped with a variety of sub stages including tensile, heating and cooling stages for in situ experimentation.

Molycorp Reports First Quarter 2012 Results
Molycorp, Inc. has announced financial and operating results for the first quarter 2012.

“The start of 2012 has been tremendously productive as we continue to hit each of our major milestones on the path to completion of Project Phoenix,” said Mark Smith, president and CEO.  “The start up of our concentrate production circuit is a major accomplishment for the Company.  I could not be more proud of the effort the Molycorp family has devoted to get to this point, especially in light of the more than 2.3 million hours we have worked in the construction of Project Phoenix without a lost time incident. As we continue to build out Project Phoenix to its full Phase 1 and Phase 2 capacities, we remain on track to establish one of the world’s premiere and fully integrated rare earths and rare metals companies.”

Smith continued, “We expanded our sales of XSORBX during the quarter, and we look forward to the opportunities and potential synergies that will arise from our pending acquisition of Neo Material Technologies.”

QUARTERLY RESULTS
Quarterly net sales were $84.5 million, significantly higher than $26.3 million in the first quarter of 2011.  Molycorp Silmet (Sillamäe, Estonia) and Molycorp Metals & Alloys (Tolleson, Arizona) were acquired during the second quarter of 2011, which contributed revenue during Q1 2012.  Even though the first quarter is traditionally soft due the impact of the extended Chinese New Year holiday, we were able to achieve significantly higher revenue this quarter versus the first quarter of 2011. 

Gross profit was $31 million during the quarter, compared to gross profit of $9.6 million during the prior year period.  Gross margin of 36.7 percent increased 23 basis points from the prior year period.

Molycorp’s first quarter GAAP earnings attributable to common stockholders was negative $6.3 million, or a loss of $0.07 per diluted share. Adjusted earnings of $0.18 per diluted share reflects certain non-cash, out-of-ordinary, and business expansion items as compared to US GAAP earnings per share, (e.g. a one-time non-cash expense of $6.6 million related to a foreign currency forward contract, $6.6 million in consolidated inventory write-downs, and $2.5 million related to bad debt expense).

2012 OUTLOOK
As of May 2012, the company is re-affirming its annual production of REO equivalent products to be in a range of 8,000 mt to 10,000 mt for the full year across all of its facilities.  Molycorp continues to believe it is well positioned for year-over-year sales growth, given existing customer orders and a growing pipeline of global business opportunities. 

White Paper on the Management of Thorium and Uranium in Rare Earth Mineral Processing Now Available from REITA
The Rare Earth Industry and Technology Association (REITA) has released the first in a series of white papers devoted to taking a balanced look at a wide variety of issues important to rare earth supply chain stakeholders.

“Handling and Management of Thorium and Uranium in Mining and Processing of Rare Earth Minerals” is available for downloading on the White Papers page of the REITA website http://www.reitaglobal.org.  

The white paper contains background information on a variety of issues related to the effective recovery and management of thorium and/or uranium.  “On the one hand we cover issues related to the known health effects from thorium and uranium exposure in addition to the major exposure pathways for workers and the environment in mining and milling operations,” said the white paper’s author, Brian Park of the Center for Advanced Mineral and Metallurgical Processing (CAMP) at Montana Tech.

“On the other hand the paper also gets into the regulatory issues and procedures from International Atomic Energy Agency (IAEA) guidance documents on the permitting process, and finishes with four case studies describing how current and prospective rare earth operations are approaching these issues.  Numerous internet references are also provided for the interested reader if they desire to learn more,” said Park.

“Brian and his collaborators have done an excellent job in documenting how the very real risks associated with the removal of Thorium and Uranium from rare earth minerals can be accomplished and managed safely protecting workers and the environment,” said Keith Delaney, REITA’s executive director.  “One of REITA’s guiding principles is that environmental excellence must be applied throughout rare earth supply chains, and this paper demonstrates that worker and environmental health are imperatives that can be totally compatible with the commercialization of rare earth resources in a variety of global jurisdictions.”

For more informationn about REITA visit the website or contact Keith Delaney at keith.delaney@reitaglobal.org

BEI Kimco Magnetics Announces New Stocking Program for Faster Voice Coil Actuator Delivery and Improved Design Process Management
BEI Kimco Magnetics, a brand of Custom Sensors & Technologies (CST), Inc., has announced the Voice Coil Actuator (VCA) Stock Program. Designed to reduce lead time, the new stock program offers customers express VCA delivery.
 
"The new program identifies the most frequently used products and defines the safety stock quantity for each model," said Gareth Yiu, Product Marketing specialist. "The ultimate goal is to provide customers with the confidence that the product they need is in stock and can be processed within hours of order entry."
 
Engineers can now have the product in hand for prototyping, beta testing, and pilot production without waiting the standard 12-week production time. Delivery can be shortened by up to 80 percent. This improves BEI Kimco's response time and allows customers to better manage their design process, especially during the critical stage in their design cycle.
 
Included in the stocking program are more than 30 voice coil actuator models covering the company's Rotary and Linear products, cylindrical un-housed, cylindrical semi-housed, and cylindrical housed actuators.

Event Listings

Sensors Expo & Conference

June 6-7, 2012

Rosemont, IL

Sensors Expo & Conference is the only industry event in North America exclusively focused on sensors and sensor-integrated systems, providing over 25 years of technical innovation and thought leadership! The conference program is dedicated to exploring the most up-to-date innovations in sensor technology, including Big Data, MEMS, Energy Harvesting, Wireless Sensing, Measurement & Detection, and more. Sensors  identifies cutting-edge trends, explores them in an information-packed conference program and reflects those trends throughout the Expo with new product announcements, key technology-focused areas, such as Big Data, Energy Harvesting, MEMS and Wireless Pavilions, and a showcase of hundreds of products and services. Special Offer for Subscribers: Register with code A301H in advance at www.sensorsexpo.com to save on conference pass rates!

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