The Best View in Philadelphia

The University of Pennsylvania recently finished their newest addition to the campus, Penn Park, which adds a brilliant contrast to the Philadelphia skyline and gives multiple sports teams a new place to practice and engage in athletics.

Majorana Fermions, Topological Insulators and Superconductors

Magnetic diffraction pattern for a Josephson junction with a topological insulator weak link. Building on a theoretical description published in 2008 by Prof. Charles Kane and Liang Fu at Penn, Stanford researchers believe the unusual behavior is explained in terms of Majorana fermions.

Alternatives to Dark Energy

Perhaps the deepest mystery in physics today is the origin of the accelerating expansion of the universe.  Professors Khoury and Trodden work, among other things, on the possibility that it is due to a dark sector with new light degrees of freedom.  Screening mechanisms, such as chameleon and symmetron, may explain why such scalars, if light, have escaped detection.

 

Jammed States of Matter

Almost any system composed of discrete pieces large enough that thermal fluctuations can be ignored can have a jamming transition: a point at which fluid flow is impeded by a change of state into a stable amorphous solid.  The behavior is general enough to explain a pile of sand, a jar of candies, or cars in a traffic jam.  Professor Andrea Liu was involved in recent theoretical breakthroughs in the study of this phenomenon.

 

Molecular Electronics

A synthetic peptide candidate that can be used for single molecule electronic measurements.  Single molecules can act as a functioning part of a field effect transistor device as studied in Professor Charlie Johnson's lab.

 

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