Dr. Sudeep Ghosh, Indian Institute of Technology Kanpur
Time-reversal symmetry breaking in superconductors
Superconductivity and magnetism are antagonistic states of matter. The presence of spontaneous magnetic fields inside the superconducting state is, therefore, an intriguing phenomenon prompting extensive experimental and theoretical research. In this talk, I will first introduce such novel unconventional superconductors which spontaneously break time-reversal symmetry. Then, I will talk about recent progress in understanding the nature of different classes of these superconductors and their properties.
Dr. Sambit Mohapatra, Centre for Nanosciences and Nanotechnologies, CNRS, Université Paris-Saclay
Toward direct thermodynamic measurements of quantum Hall states
Quantum Hall effect is one of the most fascinating subjects in the condensed matter research. Despite over forty years of intensive research, only recently have experiments shown the importance of thermodynamic investigations of low-dimensional and mesoscopic systems. In this talk, I shall present how we are developing the nanotechnology required to directly and experimentally probe the thermodynamics of quantum Hall states, in particular to directly measure the specific heat capacity of a thin layer of electron system. First, I shall very briefly introduce the quantum Hall states and explain the state-of-the art experimental efforts in achieving high mobility semiconductors, indispensable for observing such states. Next, I shall introduce the motivation behind my idea to study the quantum Hall thermodynamics experimentally. And finally, I shall present to you the technology I developed in our cleanroom for the above study. This will also include the delicate thermal measurement technique for an electron layer.