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Nikhitha Nunavath

Publications and source records attributed to Nikhitha Nunavath.

3 recordsLinked to original sources

Communicating Properties of Quantum States over Classical Noisy Channels

Transmitting information about quantum states over classical noisy channels is an important problem with applications to science, computing, and sensing. This task, however, poses fundamental challenges due to the exponential scaling of state space with system size. We introduce shadow tomography-based transmission with unequal error protection (STT-UEP), a novel communication protocol that enables efficient transmission of properties of quantum states, allowing decoder-side estimation of arbitrary local Pauli observables. Unlike conventional approaches requiring the transmission of a number of bits that is exponential in the number of qubits, STT-UEP achieves communication complexity that scales logarithmically with the number of observables, depending on the observable weight. The protocol exploits classical shadow tomography for measurement efficiency, and applies unequal error protection by encoding measurement bases with stronger channel codes than measurement outcomes. We provide theoretical guarantees on estimation accuracy as a function of the bit error probability of the classical channel, and validate the approach against several benchmarks via numerical results.

quant-ph

Quantum Teleportation using Quantum Candies

Quantum Candies or Qandies provide us with a lucid way of understanding the concepts of quantum information and quantum science in the language of candies. The critical idea of qandies is intuitively depicting quantum science to the general public, making sense as most of the research in this domain is funded by the taxpayers. The qandies model is already used to explain the essential concepts of quantum science and quantum cryptography. However, teleportation and related concepts are yet to be explained. Motivated by this fact, we investigate and extend the idea of Jacobs and Lin-Mor-Shapira to explain teleportation using qandies. Here, we explicitly design the teleportation protocol and perform a circuit model using qandy gates. The protocol is successful when the correlated qandies are appropriately pre-shared and use of some local operations at both ends. The model we develop can be a valuable tool for science and engineering educators who want to help the general public to gain more insights into quantum science and technology.

physics.pop-ph

Open quantum system dynamics of $X$-states: Entanglement sudden death and sudden birth

The origin of disentanglement for two specific sub-classes of $X$-states namely maximally nonlocal mixed states (MNMSs) and maximally entangled mixed states (MEMSs) is investigated analytically for a physical system consisting of two spatially separated qubits interacting with a common vacuum bath. The phenomena of entanglement sudden death (ESD) and the entanglement sudden birth (ESB) are observed, but the characteristics of ESD and ESB are found to be different for the case of two photon coherence and single photon coherence states. The role played by initial coherence for the underlying entanglement dynamics is investigated. Further, the entanglement dynamics of MNMSs and MEMSs under different environmental noises namely phase damping, amplitude damping and RTN noise with respect to the decay and revival of entanglement is analyzed. It's observed that the single photon coherence states are more robust against the sudden death of entanglement indicating the usability of such states in the development of technologies for the practical implementation of quantum information processing tasks.

quant-ph