2015年4月25日星期六

Quantum Hall effect: Quantization of 'surface Dirac states' could lead to exotic applications -- ScienceDaily

Quantum Hall effect: Quantization of 'surface Dirac states' could lead to exotic applications -- ScienceDaily

Topological insulators are an unusual type of material, which do not conduct electricity in the inside but only on the surfaces. Their surfaces are populated by massless electrons and electron holes--known as Dirac fermions--which can conduct electricity in a nearly dissipationless fashion, like a superconductor. As a result, their properties are being studied in an intense way with the hope of creating low-power consumption electronic devices. However, impurities in the crystal structures of these topological conductors have, up to now, made it difficult to realize this potential.

In the current research, published in Nature Communications, the group was able to overcome these limitations through careful engineering of the material. The group fabricated a 3D topological conductor made from bismuth, antimony, and tellurium, successfully eliminating the impurities that have plagued previous efforts. By fixing the material on an indium phosphide semiconductor substrate and then placing an insulating oxide film and electrodes on top, they transformed the films into electric gating devices known as "field effect transistors," and measured the Hall resistance, a type of electric resistance, while tuning the strength of the electric field, using a constant magnetic field. By doing this, they were able to show that the resistance became constant at certain plateaus, demonstrating the presence of the quantum Hall effect in the material.

In addition, by tuning the external voltage placed on the films, they were able to show that the Dirac states could be switched between the integer quantum Hall state and insulating state by changing the electrical current.

According to Ryutaro Yoshimi of the Strong Correlation Physics Research Group, who led the research, "It was very exciting to see this exotic effect in a 3D topological insulator, and we plan to continue our work to show how materials can be finely tuned to have various electronic properties. In the future, these results could I hope be used for the creation of high-speed and low-power-consumption electronic elements."


Welcome to SUV System Ltd!

SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.

We have built up long term business relationship with about many companies which are stockers and authorized agents. we have a steady and reliable supply to meet customer's demands to the greatest extent .Confidently, we are able to lower your cost and support your business with our years of professional service.

SUV System Ltd is Electronic Components Distributor Supplies,Find Quality Electronic Components Supplies Products IC(Integrated Circuits),Connectors,Capacitor,Resistors,Diodes,Transistors,LED at Suvsystem.com. Sourcing Other Energy, Environment, Excess Inventory Products from Manufacturers and Suppliers at Suvsystem.com

Electronic Components distributor:http://www.suvsystem.com

Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html

IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html

LED Distributor:http://www.suvsystem.com/l/LED-1.html

Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html

Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html

Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html

Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html

SUV System Ltd insists on the managing faith ofsincereness,speciality,foresight, win-win,so we build up stable-relationship customers located all over the world, including the States, Europe, Argentina, UAE, Malaysia, Australia,and India etc

we are focus on the following fields,and hope we can help you.


AVX Resistors Resistors TOSHIBA Diodes Switching Diodes ROHM Resistors Vishay resistors NXP Transistors Ligitek LED Chip Inductors ELPIDA IC High Precision Resistors Diodes Inc Texas Instruments(TI) IC Microchip IC Renesas parts IC MURATA IC NXP Diodes Resistor Arrays Fast Recovery Diodes MAXIM IC Bipolar Transistors NEC Transistors TOSHIBA Transistors Transistors Thin Film Resistors Chip Fuses AD IC INTERSIL IC ALTERA IC components Electronic News Zener Diodes FAIRCHILD diodes Freescale Semiconductor TI IC Cypress IC YAGEO Resistors Kingbrigt LED LED part Military IC
http://www.suvsystem.com/a/43485.aspx