Dr. Elnaz Pilehvar, Dr. Ehsan Amooghorban, Prof. Mohammad Kazem Moravvej-Farshi,
Volume 15, Issue 2 (7-2021)
Abstract
We investigate the propagation of the normal two-photon number state and coherent state of light through a dispersive non-Hermitian bilayer structure composed of gain and loss layers, particularly at a discrete set of frequencies for which this structure holds PT-symmetric. We reveal how dispersion and gain/loss-induced noises in such a bilayer structure affect the antibunching property of the incident light. For this purpose, we have calculated the second-order coherence of the output state of the bilayer. Varying the loss layer coefficient, we show that the antibunching property of the incident light only retains to some extent, for small values of loss coefficient for the transmitted number state.
Mojgan Momeni-Demneh, Ali Mahdifar, Rasoul Roknizadeh,
Volume 16, Issue 1 (1-2022)
Abstract
ABSTRACT—One of the nonlinear optical phenomena which arise out of a χ(3) nonlinearity, is the intensity dependence of the refractive index. In this paper, we describe this phenomenon based on the nonlinear coherent states approach. We show that the deformed two-dimensional oscillator algebra can be used to describe this nonlinear optical system. Then, we construct the nonlinear coherent states for this nonlinear optical system and study their quantum statistical properties. Finally, we find that by changing nonlinearity of the media, it is possible to control the nonclassical properties of the system.
Hoda Sadat Lotfipour, Majid Khodabandeh, Zahra Bagheri, Hassan Sobhani,
Volume 16, Issue 2 (7-2022)
Abstract
This paper describes the second-order coherence degree of photons produced in SPDC. First, the nonlinear BBO crystal generates the twin correlated signal and idler photons in the experimental setup. Then, g2 (0) is obtained experimentally via Hanbury Brown-Twiss set-up for investigation of the light source nature. The results show this value is less than 1 which verifies the generated photons are in the heralded single photon (HSP) regime.
Arash Tirandaz,
Volume 16, Issue 2 (7-2022)
Abstract
A generalized Born-Markov master equation for describing inelastic tunneling under non-equilibrium interaction is recommended. Rate equations are extracted and analyzed for reaching maximization in tunneling rates. Possible rooms for reviving quantum coherence despite the role of the environment have been surveyed. The scheme extended in this article can provide a general framework for the analysis of quantum tunneling in different realms of quantum optics and quantum biology. It is shown how the non-equilibrium character of the system-environment interaction may strengthen the chance of predominance probability of occurrence of inelastic tunneling against elastic tunneling despite the usual expectation.
Zohre Mahmoudi Meimand, Omid Hamidi, Ali Reza Bahrampour,
Volume 16, Issue 2 (7-2022)
Abstract
ta charset="UTF-8" >In This paper a ground-state cooling method for bad optomechanical systems is proposed. Previous authors show that an optical cavity with equal loss and gain has a parity-time reversal (PT) symmetry. We introduced an optomechanical cavity coupled to the two modes of a PT symmetry and a passive optical cavity. A quarter-wave plate provides linear mixing interaction between the PT symmetry and passive cavities. In this study, our proposed system improved the cooling rate by utilizing two effects: energy localization and quantum interference. These two impacts increase the cooling rate while the system is red or blue-detuned. It is demonstrated that optomechanical cooling occurs in both the bad-cavity limit and the weak optomechanical coupling regime. These innovations can be attained by parameter management of the system.
Arash Tirandaz,
Volume 17, Issue 2 (6-2023)
Abstract
A quantum demon is a thought experiment in quantum mechanics that describes a hypothetical being that can manipulate individual quantum states, violating the second law of thermodynamics. It is shown how the interaction-free measurement of the observers on a macroscopic thermal field, can make a superposition of cat states even at high-temperature limits. The ability of Alice and Bob to reduce the entropy of the fields without disturbing it directly is surveyed. Then, they can act as quantum demons. Investigation of making cat states under non-equilibrium conditions and the change in the Heisenberg uncertainty relation has been surveyed. Finally, we have also introduced the temperature-dependent Bell’s inequality and studied the change in the limit of violation according to the non-equilibrium character of the dynamics.