Browsing by Author "Yesilyurt, Can"

Now showing 1 - 7 of 7

Citation Count: 19
Constructing quantum logic gates using q-deformed harmonic oscillator algebras
(Springer, 2014) Altintas, Azmi Ali; Ozaydin, Fatih; Yesilyurt, Can; Bugu, Sinan; Arik, Metin
We study two-level q-deformed angular momentum states, and using q-deformed harmonic oscillators, we provide a framework for constructing qubits and quantum gates. We also present the construction of some basic one-qubit and two-qubit quantum logic gates.
Citation Count: 28
Deterministic local doubling of W states
(Optical Soc Amer, 2016) Yesilyurt, Can; Bugu, Sinan; Ozaydin, Fatih; Altintas, Azmi Ali; Tame, Mark; Yang, Lan; Ozdemir, Sahin Kaya
In large quantum systems, multipartite entanglement can be found in many inequivalent classes. Preparing states of arbitrary size in different classes is important for performing a wide range of quantum protocols. W states, in particular, constitute a class with a variety of quantum networking protocols. However, all known schemes for preparing polarization encoded photonic W states are probabilistic, with resource requirements increasing at least sub-exponentially. We propose a deterministic scheme for preparing W states of size of any power of 2, which requires no prior entanglement and can be performed locally. We introduce an all-optical setup that can efficiently double the size of W states of arbitrary size. Our scheme advances the use of W states in real-world quantum networks and could be extended to other physical systems. (C) 2016 Optical Society of America
Citation Count: 71
Enhancing the W-state quantum-network-fusion process with a single Fredkin gate
(Amer Physical Soc, 2013) Bugu, Sinan; Yesilyurt, Can; Ozaydin, Fatih
Integrating a single Fredkin (controlled swap) gate to the previously introduced W state fusion mechanism [Ozdemir et al., New J. Phys. 13, 103003 (2011)] and using an ancillary photon, we increase the size of the fused W states and essentially, we improve the success probability of the fusion process in a promising way for a possible deterministic W-state fusion mechanism. Besides fusing arbitrary size W states, our setup can also fuse Bell states to create W states with a success probability 3/4 which is much higher than the previous works. Therefore using only this setup, it is now possible to start with Bell pairs to create and expand arbitrary size W states. Since a higher probability of success implies a lower cost of resource in terms of the number of the states spent to achieve a target size, our setup gives rise to more cost-efficient scenarios. DOI: 10.1103/PhysRevA.87.032331
Citation Count: 68
Fusing multiple W states simultaneously with a Fredkin gate
(Amer Physical Soc, 2014) Ozaydin, Fatih; Bugu, Sinan; Yesilyurt, Can; Altintas, Azmi Ali; Tame, Mark; Ozdemir, Sahin Kaya
We propose an optical scheme to prepare large-scale entangled networks of W states. The scheme works by simultaneously fusing three polarization-encoded W states of arbitrary size via accessing only one qubit of each W state. It is composed of a Fredkin gate (controlled-swap gate), two fusion gates [as proposed in S. K. Ozdemir et al., New J. Phys. 13, 103003 (2011)], and an H-polarized ancilla photon. Starting with three n-qubit W states, the scheme prepares a new W state with 3(n - 1) qubits after postselection if both fusion gates operate successfully, i.e., a fourfold coincidence at the detectors. The proposed scheme reduces the cost of creating arbitrarily large W states considerably when compared to previously reported schemes.
Citation Count: 51
An optical gate for simultaneous fusion of four photonic W or Bell states
(Springer, 2013) Yesilyurt, Can; Bugu, Sinan; Ozaydin, Fatih
In order to create large-scale polarization entangled W states, there have been several proposals and some experimental demonstrations. An outstanding proposal is a simple setup which probabilistically fuses two W states of arbitrary sizes n >= 3 and m >= 3, creating a W state of size n + m - 2 (Ozdemir et al., in: New J Phys 13:103003, 2011). Using this setup as building blocks, we propose a new setup which can fuse four W states simultaneously. The proposed setup can fuse W states of size 2, i.e. Bell states, as well. We study the resource cost of our fusion process for two main scenarios, i.e. starting from sizes 2 and 3. We present some cost efficient cases, as compared to the previous work.
Citation Count: 22
Quantum Fisher Information of N Particles in the Superposition of W and GHZ States
(Springer/plenum Publishers, 2013) Ozaydin, Fatih; Altintas, Azmi Ali; Bugu, Sinan; Yesilyurt, Can
We investigate the quantum Fisher information of a multipartite entangled state of N particles in a superposition of W and GHZ states. We find that the mean quantum Fisher information per particle (RMQFI) decreases with respect to the number of the particles and the peak is observed between 0.6 and 0.8 values of the superposition coefficient of W state. We present the behavior of RMQFI for N from 2 to 10 and discuss some interesting results.
Citation Count: 18
Quantum Fisher Information of Several Qubitsin the Superposition of A GHZ and two W Stateswith Arbitrary Relative Phase
(Springer/plenum Publishers, 2014) Ozaydin, Fatih; Altintas, Azmi Ali; Bugu, Sinan; Yesilyurt, Can; Arik, Metin
We study the quantum Fisher information (QFI) of a system of several particles which is in a superposition of a GHZ and two W states with arbitrary relative phase. We show that as the number of particles increases from 3 to 4, the behavior of QFI drastically changes. We also show how the dependence of QFI on the relative phase weakens as the number of particles increases. We also analyze the QFI for the state for several instances of N due to the change of the relative phases.