Menu
Scientific developments
NASA's WISE Mission Captures Black Hole's Wildly Flaring Jet

Climatic Fluctuations Drove Key Events in Human Evolution, Researchers Find

Researchers Discover How 'Promiscuous Parasites' Hijack Host Immune Cells

Using Human Genomes to Illuminate the Mysteries of Early Human History

Carnivorous Plant Inspires Coating That Resists Just About Any Liquids

From the Comfort of Home, Web Users May Have Found New Planets

Aquarium Fishes Are More Aggressive in Reduced Environments, New Study Finds

Bioengineers Reprogram Muscles to Combat Degeneration

Asia Was Settled in Multiple Waves of Migration, DNA Study Suggests

Some Brain Wiring Continues to Develop Well Into Our 20s

Evolutionary Tree of Life for Mammals Greatly Improved

Nitrate Levels Rising in Northwestern Pacific Ocean

Nanoscale Nonlinear Light Source Optical Device Can Be Controlled Electronically

Cloaking Magnetic Fields: First Antimagnet Developed

Nature Offers Key Lessons On Harvesting Solar Power, Say Chemists

Monkeys Also Reason Through Analogy, Study Shows

Invasion of Genomic Parasites Triggered Modern Mammalian Pregnancy, Study Finds

Jumping Gene Enabled Key Step in Corn Domestication

Salty Water and Gas Sucked Into Earth's Interior Helps Unravel Planetary Evolution

People Learn While They Sleep, Study Suggests

New Technique Maps Twin Faces of Smallest Janus Nanoparticles

New 'FeTRAM' Is Promising Computer Memory Technology

Hide-And-Seek: Altered HIV Can't Evade Immune System

Scientists Reveal Molecular Sculptor of Memories

Correcting Sickle Cell Disease With Stem Cells

Physicists Move One Step Closer to Quantum Computer
Rice University physicists have created a tiny "electron superhighway" that could one day be useful for building a quantum computer, a new type of computer that will use quantum particles in place of the digital transistors found in today's microchips.

In a recent paper in Physical Review Letters, Rice physicists Rui-Rui Du and Ivan Knez describe a new method for making a tiny device called a "quantum spin Hall topological insulator." The device, which acts as an electron superhighway, is one of the building blocks needed to create quantum particles that store and manipulate data.

Today's computers use binary bits of data that are either ones or zeros. Quantum computers would use quantum bits, or "qubits," which can be both ones and zeros at the same time, thanks to the quirks of quantum mechanics.

This quirk gives quantum computers a huge edge in performing particular types of calculations, said Du, professor of physics and astronomy at Rice. For example, intense computing tasks like code-breaking, climate modeling and biomedical simulation could be completed thousands of times faster with quantum computers.

"In principle, we don't need many qubits to create a powerful computer," he said. "In terms of information density, a silicon microprocessor with 1 billion transistors would be roughly equal to a quantum processor with 30 qubits."

In the race to build quantum computers, researchers are taking a number of approaches to creating qubits. Regardless of the approach, a common problem is making certain that information encoded into qubits isn't lost over time due to quantum fluctuations. This is known as "fault tolerance."

The approach Du and Knez are following is called "topological quantum computing." Topological designs are expected to be more fault-tolerant than other types of quantum computers because each qubit in a topological quantum computer will be made from a pair of quantum particles that have a virtually immutable shared identity. The catch to the topological approach is that physicists have yet to create or observe one of these stable pairs of particles, which are called "Majorana fermions" (pronounced MAH-yor-ah-na FUR-mee-ons).

The elusive Majorana fermions were first proposed in 1937, although the race to create them in a chip has just begun. In particular, physicists believe the particles can be made by marrying a two-dimensional topological insulator -- like the one created by Du and Knez -- to a superconductor.

Topological insulators are oddities; although electricity cannot flow through them, it can flow around their narrow outer edges. If a small square of a topological insulator is attached to a superconductor, Knez said, the elusive Majorana fermions are expected to appear precisely where the materials meet. If this proves true, the devices could potentially be used to generate qubits for quantum computing, he said.

Knez spent more than a year refining the techniques to create Rice's topological insulator. The device is made from a commercial-grade semiconductor that's commonly used in making night-vision goggles. Du said it is the first 2-D topological insulator made from a material that physicists already know how to attach to a superconductor.

"We are well-positioned for the next step," Du said. "Meanwhile, only experiments can tell whether we can find Majorana fermions and whether they are good candidates for creating stable qubits."

The research was funded by the National Science Foundation, Rice University, the Hackerman Advanced Research Program, the Welch Foundation and the Keck Foundation.


First Comet Found With Ocean-Like Water

Laser Light Used to Cool Object to Quantum Ground State

Biologists Find 'Surprising' Number of Unknown Viruses in Sewage

Long-Lost Lake Agassiz Offers Clues to Climate Change

Series of Bumps Sent Uranus Into Its Sideways Spin, New Research Suggests

Venus Has an Ozone Layer Too, Space Probe Discovers

Supersaturated Water Vapor in Martian Atmosphere

Is Chivalry the Norm for Insects?

Crab Pulsar Beams Most Energetic Gamma Rays Ever Detected from a Pulsar

Subtly Shaded Map of Moon Reveals Titanium Treasure Troves

Ancient Climate Change Has Left a Strong Imprint On Modern Ecosystems

Astrophysics and Extinctions: News About Planet-Threatening Events

Giant 'Kraken' Lair Discovered: Cunning Sea Monster That Preyed On Ichthyosaurs


Menu
Easily Embarrassed? Study Finds People Will Trust You More

Stardust Discovered in Far-Off Planetary Systems

Galaxy Caught Blowing Bubbles

Sharks Are in Trouble, New Analysis Confirms

Engineers 'Cook' Promising New Heat-Harvesting Nanomaterials in Microwave Oven

NASA Space Telescope Finds Fewer Asteroids Near Earth

Scientists Release Most Accurate Simulation of the Universe to Date

'Superfast' Muscles Responsible for Bat Echolocation

Space Telescopes Reveal Secrets of Turbulent Black Hole

'Alarm Clock' Gene Explains Wake-Up Function of Biological Clock

Mechanism Uncovered for the Establishment of Vertebrate Leftright Asymmetry

Astronomers Reveal Supernova Factory

Reefs Recovered Faster After Mass Extinction Than First Thought

Gravitational Waves That Are 'Sounds of the Universe'

Decline and Recovery of Coral Reefs Linked to 700 Years of Human and Environmental Activities

Unprecedented Arctic Ozone Loss Last Winter

'Mirage-Effect' Helps Researchers Hide Objects

Electricity from the Nose: Engineers Make Power from Human Respiration

Natural Compound Helps Reverse Diabetes in Mice

Physicists Move One Step Closer to Quantum Computer

Pumice Proposed as Home to the First Life Forms

Arctic Sea Ice Continues Decline, Hits Second-Lowest Level

Sociability May Depend Upon Brain Cells Generated in Adolescence

Last Universal Common Ancestor More Complex Than Previously Thought

Monkeys 'Move and Feel' Virtual Objects Using Only Their Brains