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.
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. Shrikant Utagi,
IIT Madras
Quantum Error Correction for non-Markovian Noise
Recently, there has been renewed interest among theorists to investigate the theory of quantum error correction (QEC) beyond the white noise limit. By giving a brief overview of open system theory, we will address the question of QEC and approximate QEC for non-Markovian noise. Using the well known Petz recovery map, we first show that conditions for approximate QEC can be easily generalized for the case of non-Markovian noise, in the strong coupling regime where the noise map becomes non-completely-positive at intermediate times. While certain approximate QEC schemes are ineffective against quantum non-Markovian noise, in the sense that the fidelity vanishes in finite time, the Petz map adapted to non-Markovian noise uniquely safeguards the code space even at the maximum noise limit. Focusing on the case of non-Markovian amplitude damping noise, we further show that the non-Markovian Petz map also outperforms the standard, stabilizer-based QEC code. Since implementing such a non-Markovian map poses practical challenges, we also construct a Markovian Petz map that achieves similar performance, with only a slight compromise on the fidelity. Some implications for the scalability of quantum computers will be mentioned, leaving a number of open questions for discussions.
Dr. Kaushalya Jhuria
Indian Institute of Technology Tirupati
Beyond Moore’s Law: Harnessing Spins and Photons for the NextGeneration of Computing
As the limitations of Moore’s Law become more evident, there is a critical need for new
paradigms in information processing to meet the demands of next-generation computing. This
talk will explore how spins and photons offer a promising path beyond the capabilities of
classical computing. By leveraging quantum emitters, spintronics, and nanophotonics, we can
open up innovative approaches for data processing, communication, and storage that transcend
traditional performance limits. I will present key findings from my PhD and postdoctoral
research, including results on picosecond spin-orbit-driven magnetization switching in
ferromagnets and the programmable formation of spin-photon qubits in silicon.