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.

Premelting of Colloidal Crystals

Premelting is the localized loss of crystalline order at surfaces and defects at temperatures below the melting transition.  This result is from the lab of Prof. Arjun Yodh.


Dark Energy Studies

Professor Masao Sako uses Type Ia supernovae to study the expansion history of the universe.  The graphs show (left and middle) Hubble diagrams from a simulated 5-year Type Ia sample from the Dark Energy Survey.  The right graph shows the 95% confidence limits on dark energy parameters.

Protein-Nanotube Hybrid

The image depicts a nanobiosensor consisting of a carbon nanotube (gray) covalently attached to the coxsackie-adenovirus receptor (magenta). This device detects the adenovirus, one of the viruses responsible for the common cold, when Knob proteins from the virus capsid (orange) bind to the receptor (magenta). These devices were synthesized in Prof. Charlie Johnson's group.


Topological Insulators

Recent physics research shows how spin-orbit coupling can rearrange electronic bands in a solid to make a "topological insulator" - a new quantum phase of matter with conductive surfaces even though its bulk is insulating.  Penn physicists Professor Charlie Kane and Professor Gene Mele pioneered the theoretical discovery of such materials in 2005.