The work by Chen et. al. explores the quantum hall effect (QHE) that develops in BiSbTeSe2 at low temperatures and high magnetic fields. BiSbTeSe2 is a topological insulator, meaning it is a bulk insulating material that at low temperatures develops a quantum mechanical state that allows conduction of electrons at the surface similar to a metal. The observation of the QHE in BiSbTeSe2 is further confirmation of the theory governing these unique materials.
SmB6 has been studied for a number of years and its observed behavior had presented investigators with a conflicting set of observations that resisted explanation until recently. The observation of quantum oscillations by Li et. al. in what is a bulk insulator confirm that SmB6 becomes a topological insulator at low temperatures. A topological insulator is a material that develops a unique quantum mechanical state on its surface, which allows electrons to flow in a fashion similar to a metal.
High magnetic fields reveal the electronic interactions underlying high-temperature superconductivity in the iron pnictides. This research unifies the superconducting phase diagram of the pnictides with those of other quantum critical, high-temperature superconductors, such at the cuprates.
Researchers from Columbia University working at the MagLab have observed a physical phenomenon in bilayer graphene that could usher in a new generation of quantum computers.
Using the 45T hybrid magnet, researchers uncover the quantum Hall effect in hydrogenated graphene.
Using the 45 tesla hybrid magnet, researchers at the MagLab observed the long-predicted but never-before-seen fractal known as the Hofstadter butterfly. This work enriches our understanding of the basic physics of electrons in a magnetic field and opens a new route for exploring the role of topology in condensed matter systems.
A long-theorized phenomenon has been observed in the MagLab's high magnetic fields.
A superconducting ground state has been observed at T < 3.8 K in copper-doped Bi2Se3 single crystals. Topological superconductivity is predicted in this material, assuming the superconducting electrons follow the linear energy-momentum dispersion (Dirac-like) seen in graphene and other materials of current interest. However, this presumption had not yet been confirmed by quantum oscillation measurements.
We report two-dimensional (2D) Dirac fermions and quantum magnetoresistance (MR) in Bi square nets of CaMnBi2 crystals.
This experiment probes the nature of the 12/5 Fractional Quantum Hall state by using a hydraulic-driven rotator to tilt the two-dimensional system in a magnetic field.