Arpita Chatterjee | Jawaharlal Nehru University (original) (raw)

Papers by Arpita Chatterjee

Annalen der Physik, 2021

The significance of photon addition in engineering the single-and two-mode (bipartite correlation... more The significance of photon addition in engineering the single-and two-mode (bipartite correlations) nonclassical properties of a quantum state is investigated. Specifically, we analyzed the behavior of the Wigner function of two quasi-Werner states theoretically constructed by superposing two normalized bipartite m-photon added coherent states. This allowed us to quantify the amount of nonclassicality present in the quantum states using Wigner logarithmic negativity (WLN), while quantum correlations are measured in terms of concurrence, entanglement of formation, and quantum discord. The WLN for a two-mode state corresponds to the sum of the single-mode nonclassicality as well as quantum correlations, and both of these are observed to enhance with photon addition manifesting the efficacy of photon addition in the entanglement distillation. Usefulness of photon addition is further established by showing that the performance of the quasi-Werner states as quantum channel for the teleportation of a single-mode coherent and squeezed states, as quantified via teleportation fidelity, improves with the photon addition. Further, in contrast to a set of existing results, it is established that the negative values of two-mode Wigner function cannot be used in general as a witness of quantum correlation.

Journal of Physics B: Atomic, Molecular and Optical Physics, 2015

We investigate the states generated in continuous variable (CV) optical fields on operating them ... more We investigate the states generated in continuous variable (CV) optical fields on operating them with a number-conserving operator of the type sââ † + tâ †â , formed by the generalised superposition of products of field annihilation (â) and creation (â †) operators, with s 2 + t 2 = 1. Such an operator is experimentally realizable and can be suitably manipulated to generate nonclassical optical states when applied on single-and two-mode coherent, thermal, and squeezed input states. At low intensities, these nonclassical states can interact with a secondary mode via a linear optical device to generate two-mode discrete entangled states, which can serve as a resource in quantum information protocols. The advantage of these operations are tested by applying the generated entangled states as quantum channels in CV quantum teleportation, under the Braunstein and Kimble protocol. We observe that, under these operations, while the average fidelity of CV teleportation is enhanced for the nonclassical channel formed using input squeezed states, it remains at the classical threshold for input coherent and thermal states. This is due to the fact that though these operations can introduce discrete entanglement in all input states, it enhances the Einstein-Podolosky-Rosen (EPR) correlations only in the nonclassical squeezed state inputs, leading to an advantage in CV teleportation. This shows that nonclassical optical states generated using the above operations on classical coherent and thermal state inputs are not resourceful for CV teleportation. This investigation could prove useful in efficient implementation of noisy non-Gaussian channels, formed by linear operations, in future teleportation protocols.

International Journal of Theoretical Physics, 2007

In this paper we study quantum mechanical phase distribution of some nonlinear optical phenomena ... more In this paper we study quantum mechanical phase distribution of some nonlinear optical phenomena in a general setting of interacting Fock space. We have investigated the optical phenomena of propagation through a nonlinear medium as in optical fiber and the process of photon absorption from a thermal beam. The input and output phase distribution have been investigated analytically in these two cases.

In this paper we study approximate quasi-probability distribution functions of non-classical stat... more In this paper we study approximate quasi-probability distribution functions of non-classical states such as incoherent states, Kerr states, squeezed states and k-photon coherent states in interacting Fock space.

In this paper, we study Susskind–Glogower phase distribution of entangled state in the framework ... more In this paper, we study Susskind–Glogower phase distribution of entangled state in the framework of interactions involving two modes of interacting Fock space which in its turn provides an interesting insigth into the structure of entangled state.

The quantum mechanical phase distribution and the quantum oscillations of population are studied ... more The quantum mechanical phase distribution and the quantum oscillations of population are studied for a cavity field togetherwith a driven classical field. The atom is sent through the cavity and driven by a classical field. Also the time evolution of the system including decay is obtained. The graph showing the Rabi oscillations for this system is changed into a bit pattern from the system without decay. The phase probability function is also affected due to the presence of cavity decay.

We discuss nonclassicality of a superposition of coherent states in terms of sub-Poissonian photo... more We discuss nonclassicality of a superposition of coherent states in terms of sub-Poissonian photon statistics as well as the negativity of the Wigner function. We derive an analytic expression for the Wigner function from which we find that the function has some negative region in phase space. We obtain a compact form of the Wigner function when decoherence occurs and study the effect of decoherence on the state. We demonstrate the behavior of the nonclassicality indicator. Résumé : Nous discutons le caractère non-classique d'une superposition d'états cohétents en fonction d'une distribution sous-Poisson de photons ainsi que la négativité de la fonction de Wigner. Nous trouvons une expression analytique pour la fonction de Wigner d'où nous déduisons que la fonction a des régions négatives dans l'espace de phase. Nous obtenons une forme compacte de la fonction de Wigner quand se produit la décohérence et étudions l'effet de la décohérence sur l'état. Nous montrons le comportement de l'indice de non-classicalité. [Traduit par la Rédaction]

We study the phase properties and quasiprobability distributions of different states produced in ... more We study the phase properties and quasiprobability distributions of different states produced in a cavity. The number-phase properties of the states are investigated using a methodology based on the Susskind–Glogower formalism. Also the Husimi Q-functions are obtained and illustrated graphically.

We have discussed the time evolution along with the nonclassicality phenomena of a system contain... more We have discussed the time evolution along with the nonclassicality phenomena of a system containing a vee-type three-level atom interacting with a bimodal electromagnetic field. A general expression for the atomic inversion is presented. It is found that the model undergoes Rabi oscillation. The total noise of the output state is measured.

Journal of Modern Optics Publication details, including instructions for authors and subscription... more Journal of Modern Optics Publication details, including instructions for authors and subscription information: We formulate the density matrices of a quantum state obtained by first adding multi-photons to and then subtracting multi-photons from any arbitrary state as well as performing the same process in the reverse order. Considering the field to be initially in a thermal (or in an even coherent) state, we evaluate the photon number distribution, Wigner function and Mandel's Q parameter of the resulting field. We show graphically that the order in which multi-photons are added and subtracted has a noticeable effect on the temporal behavior of these statistical properties.

We investigate the states generated in continuous variable (CV) optical fields by operating them ... more We investigate the states generated in continuous variable (CV) optical fields by operating them with a number-conserving operator of the type saa ta a ˆ ˆ ˆ ˆ † † + , formed by the generalized superposition of products of field annihilation (a ˆ) and creation (a ˆ †) operators, with s t 1 2 2 + =. Such an operator is experimentally realizable and can be suitably manipulated to generate nonclassical optical states when applied on single-and two-mode coherent, thermal and squeezed input states. At low intensities, these nonclassical states can interact with a secondary mode via a linear optical device to generate two-mode discrete entangled states, which can serve as a resource in quantum information protocols. The advantage of these operations are tested by applying the generated entangled states as quantum channels in CV quantum teleportation, under the Braunstein and Kimble protocol. We observe that, under these operations, while the average fidelity of CV teleportation is enhanced for the nonclassical channel formed using input squeezed states, it remains at the classical threshold for input coherent and thermal states. This is due to the fact that though these operations can introduce discrete entanglement in all input states, it enhances the Einstein–Podolosky–Rosen correlations only in the nonclassical squeezed state inputs, leading to an advantage in CV teleportation. This shows that nonclassical optical states generated using the above operations on classical coherent and thermal state inputs are not useful for CV teleportation. This investigation could prove useful for the efficient implementation of noisy non-Gaussian channels, formed by linear operations, in future teleportation protocols.

Journal of Physics B: Atomic, Molecular and Optical Physics, 2014

We consider a generalized Jaynes-Cummings model of a two-level atom interacting with a multimode ... more We consider a generalized Jaynes-Cummings model of a two-level atom interacting with a multimode nondegenerate coherent field. The sum of the mode frequencies is equal to the two-level transition frequency, creating the resonance condition. The intermediate levels associated with the multiphoton process are adiabatically eliminated using the non-resonant conditions for these transitions. Under such general conditions, the infinite atom-multiphoton interaction is effectively mapped onto an equivalent reduced 2 × 2 bipartite qubit system that facilitates the study of the nonclassical features of the interaction using known information-theoretic measures. We observe that the bipartite pure system is highly entangled as quantified by its entanglement of formation. Furthermore, it is shown that the dynamics of the mapped system can be generated using optically truncated, quantum scissored states that reduce the infinite atom-multiphoton interaction to a finite 2 × k system, where k is a suitable truncation number. This allows us to introduce atomic dephasing and study the mixed state dynamics, characterized by the decay of quantum correlations such as quantum discord, which is observed to be more robust than entanglement. The quantum correlation dynamics of the dissipative system qualitatively complements the behaviour of collapse and revival of the Rabi oscillations in the system. The effective mapping of the composite system proves to be an efficient tool for measuring information-theoretic properties.

Physics Letters A, 2012

We successively pass two V -type three-level atoms through a single-mode cavity field. Considerin... more We successively pass two V -type three-level atoms through a single-mode cavity field. Considering the field to be initially in a classical state, we evaluate various statistical properties such as the quasiprobability Q function, Wigner distribution, Mandel's Q parameter and normal squeezing of the resulted field. We notice that the sequential crossing of atoms induces nonclassicality into the character of a pure classical state (coherent field). The initial thermal field shows sub-Poissonian as well as squeezing property after interacting with the V atoms.

Journal of Physics B: Atomic, Molecular and Optical Physics, 2012

We consider an experimentally realizable scheme for manipulating quantum states using a general s... more We consider an experimentally realizable scheme for manipulating quantum states using a general superposition of products of field annihilation (â) and creation (â † ) operators of the type (sââ † + tâ †â ), with s 2 + t 2 = 1. Such an operation, when applied on states with classical features, is shown to introduce strong nonclassicality. We quantify the generated degree of nonclassicality by the negative volume of Wigner distribution in the phase space and investigate two other observable nonclassical features, sub-Poissonian statistics and squeezing. We find that the operation introduces negativity in the Wigner distribution of an input coherent state and changes the Gaussianity of an input thermal state. This provides the possibility of engineering quantum states with specific nonclassical features.

Annals of Physics, 2013