Quantum Mechanics

Over the last century, Quantum Mechanics has emerged as a fundamental ingredient for understanding various facets of nature such as atomic and sub-atomic physics, quantum optics and a plethora of phenomena in condensed matter physics. Modern developments in computing could be said to have started from the work of Alan Turing, while information theory was put on the pedestal of modern science by the efforts of Claude Shannon. The amalgamation of quantum physics with computing and information theory could be historically traced from the works of EPR (Einstein, Podolsky and Rosen), followed by that of John Bell and culminating in efforts made by Charles Bennett. This was further cemented by the efforts of William Wootters. Experimental developments over the last few decades have brought the subject of quantum information to the threshold of technology development.

Quantum Information and Computation

The proposed interdisciplinary research group in Quantum Information and Computation (QIC) at IIT Jodhpur will lead us towards establishing a consilience between diverse academic spaces. In this inter-disciplinary joint collaboration, we propose to study quantum correlations in nonclassical states from the perspective of a practical interface between quantum optics and quantum information processing. Such correlations occupy a central position in the quest for understanding and harvesting the power of quantum mechanics and fundamentals of quantum information processing. Another dimension would be to analyze and characterize multiqubit entangled states for establishing shared communication network among multiple users; one of the key issues in applications such as quantum key distribution, quantum dense coding, quantum teleportation, quantum cryptography, quantum game theory and quantum secure communication. The intricacy of the problem increases even further when one considers real conditions, i.e., the interaction between the principal system and environment, leading to decoherence, which adversely impacts the efficiency of quantum systems; in general. In fact, for a practical implementation of any quantum information task, it is important to consider the role of noise on the chosen task. The systematic study of quantum mechanics in realistic scenarios, including the effect of ambient noise, can be made by using ideas and techniques of Open Quantum Systems. In the proposed collaboration, we will make systematic use of Open Quantum Systems to study various facets of quantum information and computation, including quantum cryptographic tasks. Applications are invited for Ph.D. positions in Quantum Information and Computation group. Interested applicants may apply through the online Application Submission link.

Current Focus

QKD: Implement Quantum key distribution protocols like the ones by Bennet and Brassard (BB84), and by Ekert (E91). We will also be studying various physical attacks against these protocols. Further, we will also study and implement these protocols in combination with Cryptographic authentication mechanisms in order to prevent some of the physical attacks.

Quantum Crypto-analysis: In this line of work, we are studying the security of classical cryptographic algorithms such as block ciphers and hash functions against quantum adversaries. We are not only developing new attacks against such schemes, but also precisely quantifying the number of qubits and depth of the circuit for these attacks.

Quantum memory (non-Markovian): Development of techniques to analyze the role of memory in quantum communication systems.

Quantum noise can undermine the secrecy and robustness of practical quantum key distribution (QKD). This motivates the investigation of the security of relevant quantum communication systems.