Quantum exists only when you look!

Quantum Computation Group-VIT


The interest of this group is to explore the areas of quantum computing and quantum information along with the application of these concepts in quantum game theory. 

RESEARCH SPOTLIGHTS

    No-Go Theorems

Quantum computation and information use quantum mechanical systems to efficiently perform meaningful computational and information tasks. Though quantum computation is argued to be superior over the classical computation, there are tasks that cannot be achieved in the quantum domain.

No-go theorems are statements that state operations that are impossible to achieve in the description of quantum mechanics. The impossibility of perfect cloning and the impossibility of perfect deleting are two of the no-go theorems that have become core theorems in quantum information theory. These two theorems are attributable to the fact that quantum physics' linearity prevents perfect solutions, the unknown quantum states can be cloned and deleted perfectly. In light of this, we introduced a new deletion machine and observed the non-local characteristics of them. No-go theorem led to the law of conservation of quantum information theory that the information cannot be created nor destroyed in the quantum world.

Quantum Game Theory

Game theory is a mathematical model to understand the real world situations. In quantum version of classical game theory, we try to understand quantum games through quantum operators and see how these operators can be used to describe the game dynamics of both open and closed quantum systems. Currently, we are working on the role of two-qubit entangling operators in controlling the payoffs of the players in both simultaneous and sequential games. We are also trying to address the competitive market games namely duopoly games through the perspective of quantum operators. 

We have introduced a new quantization scheme named as modified Eisert-Wilkens-Lewenstein scheme to explore a wide range of two-qubit entangling operators which is otherwise not possible using the traditional EWL and MW scheme. 



Quantum Communication and Information Theory

Qubits are the building blocks of quantum communication and cryptography. The overwhelming power of quantum communication over classical communication inspired us to work in this field. Existing quantum communication protocols are analyzed and studied on the basis of their reliability, practical possibility, quantum efficiency, noise effects, and the role of eavesdroppers.

Currently, our work is more inclined to quantum bidirectional communication protocols. Recently, damping studies were done on an existing protocol, and the effects of damping and the intruder were distinguished the same. We are trying to develop a quantum dialogue protocol that should be secure, simple, efficient, and practically feasible, considering the noise effects also.  

Quantum Networks

A quantum network creates a link between two or more distant parties to communicate the quantum information. The network involves several nodes, quantum gates, and quantum channels and the information is transferred by exchanging qubits. The main concern in quantum communication is to protect the qubit from external distortion causing decoherence.

We have successfully implemented the quantized cop and robber game on the quantum network using a peer-to-peer scheme. Further, the quantum network is analyzed under several noise conditions. Mainly, amplitude damping, phase damping, phase flip damping, and bit-flip damping noise models are studied to understand their effect on the fidelity of the transferred quantum state.