New energy pattern observed at National High Magnetic Field Laboratory
2013-05-17 0:00

By Thomas Anderson | TGDaily

Two research teams at the National High Magnetic Field Laboratory (MagLab) smashed through a nearly 40-year barrier recently when they observed a never-before-seen energy pattern.

The butterfly-shaped pattern was first theorized by physicist Douglas Hofstadter in 1976, but it took the tools and technology now available at the MagLab to prove its existence.

"The observation of the ’Hofstadter butterfly’ marks a real landmark in condensed matter physics and high magnetic field research," said Greg Boebinger, director of the MagLab. "It opens a new experimental direction in materials research."

This groundbreaking research demanded the ability to measure samples of materials at very low temperatures and very high magnetic fields, up to 35 tesla. Both of those conditions are available at the MagLab, making it an international destination for scientific exploration.

The unique periodic structure used to observe the butterfly pattern was composed of boron nitride (BN) and graphene. Graphene is a Nobel Prize-winning material that holds tremendous promise in revolutionizing computers, batteries, cell phones, televisions and even airplanes. A one-atom thick, honeycomb array of carbon atoms, graphene is virtually see-through, yet 300 times stronger than steel and 1,000 times more conducting than silicon.

"This is about a puzzle that has been solved," said Eric Palm, deputy director at the MagLab. "It is really about scientific curiosity. It is an exciting confirmation of a theory that was made years ago."

MagLab physicist Nicholas Bonesteel agreed, adding "The Hofstadter butterfly is a beautiful fractal energy pattern that has intrigued physicists for decades. Seeing clear experimental evidence for it is a real breakthrough."

[...]

Read the full article at: tgdaily.com




What the teams did was place graphene – a layer of carbon just one atom thick – on an extremely flat surface of a boron-nitride crystal. As both materials have similar hexagonal structures, the researchers observed "Moiré patterns", which are regular patterns created whenever two similar 2D lattices are overlaid. (The Manchester and MIT groups used single-layer graphene, while the Columbia-led experiment involved bilayer graphene.) By tweaking the relative orientation of the two lattices, the teams were able to create superlattices with appropriate spacing. Source


Butterfly seen at long last





Related Articles
Nature: Hofstadter’s butterfly and the fractal quantum Hall effect in moiré superlattices
Scientists use magnetic nano-rods to investigate how matter assembles
New Discovery Provides Unprecedented Control of Magnetic Fields


Latest News from our Front Page

UK Police Tell Subjects Not to Harm Their Attackers, Get a Rape Alarm
2015-07-01 1:17
The latest dispatch from the United Kingdom’s ongoing campaign to eliminate all forms of armed self-defense seems too incredible to be true. Unfortunately, after tracking down the origin of a publicly distributed statement regarding self-defense products on the country’s “Ask the Police” website, we can confirm that British subjects continue to live at the mercy of their potential attackers.  Even ...
Activists Plan to Burn American Flags in New York City Ahead of Fourth of July
2015-07-01 1:52
Burning the flag in Charleston, South Carolina on June 22, 2015 A group calling for the immediate disarmament of the New York Police Department plans to burn American flags in a Brooklyn park on Wednesday, just days before the Fourth of July holiday. “Disarm NYPD” announced the “Burn the American Flags” event on Facebook, inviting individuals to join the organization at Fort ...
Ruiz: Diversity of New York City languages makes staying involved in kids’ education difficult for immigrant parents
2015-07-01 1:08
Immigrant parent seek better translation and interpretation services from the Department of Education at the New York Immigration Coalition. New Yorkers, who come from every corner of the world, speak 180 languages. Not surprisingly, nearly half of public school students speak a language other than English at home. This makes life difficult for the city's Department of Education, which, according to federal ...
Ethnic Studies to Become Mandatory in Sacramento Schools by 2016
2015-06-30 22:36
The fourth most diverse school district in the nation is finally adding an ethnic studies graduation requirement—in 2020. The Sacramento City Unified School District's Board of Trustees unanimously approved the proposal from its Student Advisory Council on June 4. The proposal will create an ethnic studies pilot program for fall 2016. In collaboration with community organizations, local university professors and college students, ...
It Begins: New Calls To Strip Churches of Tax Exempt Status After Same-Sex Marriage Ruling
2015-06-30 20:22
For years conservatives and proponents of religious liberty in America have warned that if same-sex marriage became legal, the left would then pursue revoking the tax exempt status for religious institutions, particularly Christian churches, around the country. Just days after the Supreme Court ruled in a 5-4 decision that gay marriage is a constitutional right, progressive activists like Mark Oppenheimer of ...
More News »