After her MBA degree, Sebastian worked as a management consultant for a few years. She then decided to pursue physics as a career, and joined Stanford University for doctoral studies. Suchitra Sebastian's doctoral research was into barium copper silicate's transformation from a non-magnetic into a magnetic insulator under high magnetic field and low temperature. She discovered that the point of phase transition, the quantum critical point, occurs when the electrons' behaviour becomes two-dimensional, with the third dimension having almost no effect. In 2006, she co-published a paper revealing these findings. When the silicate is in its insulating state, the electron spins cancel each other out, but in the magnetic phase, under strong magnetic fields and low temperatures, the electrons form a Bose-Einstein condensate, with the electron spins suddenly unified. At the critical point, the spins from parallel layers stop affecting each other, and the magnetic waves stay within the plane of each layer, propagating in two dimensions. Sebastian's experiment was the first exploration of the immediate neighbourhood of the critical point in Bose-Einstein condensates. In 2015, Sebastian received a five-year grant from the European Research Council to work with cuprates to determine why they behave as high temperature superconductors. This entailed the suppression superconductivity under strong magnetic fields, and the examination of their resistive state. This revealed that electrons were forming twisted pockets in the weakest areas of superconductivity, in contrast to other researchers' finding that pockets formed in strong superconductive regions. She also discovered that the waves formed by alignment of electrons by their charge, called charge ordering, produce the pockets that are involved in the substance's superconductivity. In 2015, Sebastian and her team discovered that samarium hexaboride, an insulator at low temperatures, displays simultaneous conduction-like properties under strong magnetic fields. Samarium hexaboride also belongs to the class of topological insulators, which are insulators within their bulk but conductive on their surface. Sebastian found that samarium hexaboride acts as a simultaneous conductor and insulator within its bulk.
