Professor Lu Li and research team including graduate students Tomoya Asaba and Benjamin Lawson are first to discover rotational symmetry breaking in a magnetic property of an unconventional superconductor. Since the discovery of the topological insulator, a new phase of matter where electrons can only move on the material surface, scientists have been interested to discover another, more exotic phase of matter – topological superconductivity. Lu Li and his team found that the topological insulator, bismuth selenide (Bi2Se3), when doped with niobium becomes superconducting and a potential candidate to realize this new physical phenomena. By applying a magnetic field, they discovered this material’s magnetic response is much stronger in one particular direction. Although the atoms in the crystal are oriented in triangles, the crystal’s magnetic property doesn’t follow this symmetry. This is called “rotational symmetry breaking” and was predicted to be a property of the sought-after topological superconductor.

As the demand for faster and more volume of information processing arises, so does the search for superconductor elements that can ultimately lead to the building of a topological quantum computer. The quest to build a quantum computer has been very difficult because the quantum states that make such a computer work are easily destroyed. However, there is a prediction that a very robust quantum computer could be made from a Majorana Fermion, an exotic particle that is its own antiparticle. A new theory predicts that rotational symmetry breaking would help confirm the existence of Majorana Fermions in a topological superconductor. This new discovery of rotational symmetry breaking could pave the way for realizing this new technology, which may be the silicon of the next generation of computers.

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