arXiv subjects

Seyed Mahmoud Ashrafi

Publications and source records attributed to Seyed Mahmoud Ashrafi.

4 recordsLinked to original sources

arXiv2023

Single-photon generation at room temperature using molecular optomechanics in a hybrid photonic-plasmonic cavity

We propose a novel integrated structure for single photon generation at room temperature based on a molecular optomechanics system in a hybrid photonic-plasmonic cavity. The proposed structure comprises a single molecule within a plasmonic cavity, coupled to a 2D photonic crystal resonator. In this paper, we theoretically identify the ability of the scheme through calculation second order correlation function g^2 (0) for four different coupling regimes. We demonstrate the quantum paths and the destructive interference mechanism through the selection of efficient and preferred basis. Furthermore, we find that the unconventional photon blockade effects can occurs in the weak molecular optomechanics coupling. This structure holds the potential to serve as an integrated single-photon source for quantum networks at room temperature.

physics.optics↗

arXiv2023

Quantum Multiplication Algorithm Based on the Convolution Theorem

The problem of efficient multiplication of large numbers has been a long-standing challenge in classical computation and has been extensively studied for centuries. It appears that the existing classical algorithms are close to their theoretical limit and offer little room for further enhancement. However, with the advent of quantum computers and the need for quantum algorithms that can perform multiplication on quantum hardware, a new paradigm emerges. In this paper, inspired by convolution theorem and quantum amplitude amplification paradigm we propose a quantum algorithms for integer multiplication with time complexity $O(\sqrt{n}\log^2 n)$ which outperforms the best-known classical algorithm, the Harvey algorithm with time complexity of $O(n \log n)$. Unlike the Harvey algorithm, our algorithm does not have the restriction of being applicable solely to extremely large numbers, making it a versatile choice for a wide range of integer multiplication tasks. The paper also reviews the history and development of classical multiplication algorithms and motivates us to explore how quantum resources can provide new perspectives and possibilities for this fundamental problem.

quant-ph↗

arXiv2014

New approach for Damping in a squeezed bath and its time evolution through Complete Class of Gaussian Quasi-distributions

By virtue of the thermal entangled states representation of density operator and using dissipative interaction picture we solve the master equation of a driven damped harmonic oscillator in a squeezed bath. We show that the essential part of the dynamics can be expressed by the convolution of initial Wigner function with a special kind of normalized Gaussian in phase space and relate the dynamics with the change of Gaussian ordering of density operator.

quant-ph↗

arXiv2014

New approach for solving master equations of density operator for the Jaynes Cummings Model with Cavity Damping

By introducing thermal entangled state representation which can map master equations of density operator in quantum statistics as state vector evolution equations and using dissipative interaction picture we solve the master equation of J-C model with cavity damping. In addition we derive the Wigner function for density operator when the atom is initially in the up state and the cavity mode is in coherent state.

quant-ph↗