We numerically investigate the thermal entanglements of spins (1/2, 1) and spins (1/2, 1/2) in the three-mixed (1/2, 1, 1/2) anisotropic Heisenberg XXZ spin system on a simple triangular cell under an inhomogene...We numerically investigate the thermal entanglements of spins (1/2, 1) and spins (1/2, 1/2) in the three-mixed (1/2, 1, 1/2) anisotropic Heisenberg XXZ spin system on a simple triangular cell under an inhomogeneous magnetic field. We show that the external magnetic field induces strong plateau formation in the pairwise thermal entanglement for fixed parame-ters of the Hamiltonian in the cases of ferromagnetic and antiferromagnetic interactions. We also .observe an unexpected critical point at finite temperature in the thermal entanglement of spins (1/2, 1) for the antiferromagnetic case, while the entanglement of spins (1/2, 1) in the ferromagnetic case and the entanglement of spins (1/2, 1/2) in both ferromagnetic and antiferromagnetic cases almost decay exponentially to zero with increasing temperature. The critical point in the en-tanglement of spins (1/2, 1) in the antiferromagnetic case may be a signature of the quantum phase transition at finite temperature.展开更多
The transport of externally overdriven particles confined in entropic barriers is investigated under various types of oscillating and temporal forces.Temperature,load,and amplitude dependence of the particle current a...The transport of externally overdriven particles confined in entropic barriers is investigated under various types of oscillating and temporal forces.Temperature,load,and amplitude dependence of the particle current and energy conversion efficiency are investigated in three dimensions.For oscillating forces,the optimized temperature–load,amplitude–temperature,and amplitude–load intervals are determined when fixing the amplitude,load,and temperature,respectively.By using three-dimensional plots rather than two-dimensional ones,it is clearly shown that oscillating forces provide more efficiency compared with a temporal one in specified optimized parameter regions.Furthermore,the dependency of efficiency to the angle between the unbiased driving force and a constant force is investigated and an asymmetric angular dependence is found for all types of forces.Finally,it is shown that oscillating forces with a high amplitude and under a moderate load lead to higher efficiencies than a temporal force at both low and high temperatures for the entire range of contact angle.展开更多
The relaxation behavior of complex-disordered systems, such as spin glasses, polymers, colloidal suspensions, structural glasses,and granular media, has not been clarified. Theoretical studies show that relaxation in ...The relaxation behavior of complex-disordered systems, such as spin glasses, polymers, colloidal suspensions, structural glasses,and granular media, has not been clarified. Theoretical studies show that relaxation in these systems has a topological origin. In this paper, we focus on the rotational stretched exponential relaxation behavior in complex-disordered systems and introduce a simple phase space model to understand the mechanism of the non-exponential relaxation of these systems. By employing the Monte Carlo simulation method to the model, we obtain the rotational relaxation function as a function of temperature. We show that the relaxation function has a stretched exponential form under the critical temperature while it obeys the Debye law above the critical temperature.展开更多
In this study, we deal with the holographic model of interacting dark components of dark energy and dark matter quadratic case of the equation of state parameter (EoS). The effective equations of states for the inte...In this study, we deal with the holographic model of interacting dark components of dark energy and dark matter quadratic case of the equation of state parameter (EoS). The effective equations of states for the interacting holographic energy density are derived and the results are analyzed and compared with the solution of the linear form in the literature. The result of our work shows that the value of interaction term between dark components affects the fixed points at far future in the DE-dominated universe in the case of quadratic EoS parameter; it is a different result from the linear case in the theoretical results in the literature, and as the Quintom scenario the equations of state had coincidence at the cosmological constant boundary of - 1 from above to below.展开更多
We investigate the time dependence of the survival probability of quantum walks governed by Fibonacci walks with phase parameters on the trapped two-dimensional lattice. We have shown that the survival probability of ...We investigate the time dependence of the survival probability of quantum walks governed by Fibonacci walks with phase parameters on the trapped two-dimensional lattice. We have shown that the survival probability of the quantum walk decays with time obey to the stretched exponential law for all initial states of walkers. We have also shown that stretched exponential decay parameter β can be arranged by phase parameter combination. Obtained numerical results show that phase parameters can be used as a control parameter to determine the decay rate of the survival probability of the quantum walk.展开更多
基金Project supported by˙Istanbul University(Grant Nos.19240 and 28432)
文摘We numerically investigate the thermal entanglements of spins (1/2, 1) and spins (1/2, 1/2) in the three-mixed (1/2, 1, 1/2) anisotropic Heisenberg XXZ spin system on a simple triangular cell under an inhomogeneous magnetic field. We show that the external magnetic field induces strong plateau formation in the pairwise thermal entanglement for fixed parame-ters of the Hamiltonian in the cases of ferromagnetic and antiferromagnetic interactions. We also .observe an unexpected critical point at finite temperature in the thermal entanglement of spins (1/2, 1) for the antiferromagnetic case, while the entanglement of spins (1/2, 1) in the ferromagnetic case and the entanglement of spins (1/2, 1/2) in both ferromagnetic and antiferromagnetic cases almost decay exponentially to zero with increasing temperature. The critical point in the en-tanglement of spins (1/2, 1) in the antiferromagnetic case may be a signature of the quantum phase transition at finite temperature.
基金Project supported by the Istanbul University,Turkey(Grant No.55383)
文摘The transport of externally overdriven particles confined in entropic barriers is investigated under various types of oscillating and temporal forces.Temperature,load,and amplitude dependence of the particle current and energy conversion efficiency are investigated in three dimensions.For oscillating forces,the optimized temperature–load,amplitude–temperature,and amplitude–load intervals are determined when fixing the amplitude,load,and temperature,respectively.By using three-dimensional plots rather than two-dimensional ones,it is clearly shown that oscillating forces provide more efficiency compared with a temporal one in specified optimized parameter regions.Furthermore,the dependency of efficiency to the angle between the unbiased driving force and a constant force is investigated and an asymmetric angular dependence is found for all types of forces.Finally,it is shown that oscillating forces with a high amplitude and under a moderate load lead to higher efficiencies than a temporal force at both low and high temperatures for the entire range of contact angle.
基金Project supported by Istanbul University(Grant Nos.28432 and 45662)
文摘The relaxation behavior of complex-disordered systems, such as spin glasses, polymers, colloidal suspensions, structural glasses,and granular media, has not been clarified. Theoretical studies show that relaxation in these systems has a topological origin. In this paper, we focus on the rotational stretched exponential relaxation behavior in complex-disordered systems and introduce a simple phase space model to understand the mechanism of the non-exponential relaxation of these systems. By employing the Monte Carlo simulation method to the model, we obtain the rotational relaxation function as a function of temperature. We show that the relaxation function has a stretched exponential form under the critical temperature while it obeys the Debye law above the critical temperature.
文摘In this study, we deal with the holographic model of interacting dark components of dark energy and dark matter quadratic case of the equation of state parameter (EoS). The effective equations of states for the interacting holographic energy density are derived and the results are analyzed and compared with the solution of the linear form in the literature. The result of our work shows that the value of interaction term between dark components affects the fixed points at far future in the DE-dominated universe in the case of quadratic EoS parameter; it is a different result from the linear case in the theoretical results in the literature, and as the Quintom scenario the equations of state had coincidence at the cosmological constant boundary of - 1 from above to below.
基金supported by the Istanbul Uni-versity under Project No:28432.
文摘We investigate the time dependence of the survival probability of quantum walks governed by Fibonacci walks with phase parameters on the trapped two-dimensional lattice. We have shown that the survival probability of the quantum walk decays with time obey to the stretched exponential law for all initial states of walkers. We have also shown that stretched exponential decay parameter β can be arranged by phase parameter combination. Obtained numerical results show that phase parameters can be used as a control parameter to determine the decay rate of the survival probability of the quantum walk.