K. V. S. Shiv Chaitanya

Aspects of coherent states of nonlinear algebras

Various aspects of coherent states of nonlinear su(2) and su(1, 1) algebras are studied. It is shown that the nonlinear su(1, 1) Barut–Girardello and Perelomov coherent states are related by a Laplace transform. We then concentrate on the derivation and analysis of the statistical and geometrical properties of these states. The Berrys phase for the nonlinear coherent states is also derived.

Algebraic solution of master equations in quantum optics

The techniques in thermo field dynamics are applied to solve a certain class of master equations associated with su(1,1) × su(1,1) symmetries exactly by an algebraic approach using disentanglement theorem.

A generalized master equation for Janus-faced coherent states

A general master equation for the eigenstates of Janus-faced commutation relations is constructed.

Entanglement in two-site Bose–Hubbard model with non-linear dissipation

In this paper, we study the decoherence and entanglement properties for the two-site Bose–Hubbard model in the presence of a non-linear damping. We apply the techniques of thermo field dynamics and then use Hartree-Fock approximation to solve the corresponding master equation. The expectation values of the approximated field operators appearing in the solution of master equation are computed self-consistently. We solve this master equation for a small time t so that we get the analytical solution, thereby we compute the decoherence and entanglement properties of the solution of the two-mode bosonic system. We have found that for a small initial time t, the entanglement of the system increases but at the same time the system decoheres exponentially.

Baryon asymmetry, inflation and squeezed states

We use the general formalism of squeezed rotated states to calculate baryon asymmetry in the wake of inflation through parametric amplification. We base our analysis on a B and CP violating Lagrangian in an isotropically expanding universe. The B and CP violating terms originate from the coupling of complex fields with non-zero baryon number to a complex background inflaton field. We show that a differential amplification of particle and antiparticle modes gives rise to baryon asymmetry.

Harmonic oscillator Wigner function extension to exceptional polynomials

In this paper, we construct isospectral Hamiltonians without shape invariant potentials for a harmonic oscillator Wigner function on a real line. In this case, we actually remove the ground state of the second Hamiltonian, which forms a special case,

Exceptional polynomials and SUSY quantum mechanics

m=0

Entanglement Criterion for Multi-Mode Gaussian States

m=0, of an exceptional Laguerre differential equation with solutions