183 citations · 444 across the 12 of their papers we have counts for
12 papers
Expectation Values from the Single-Layer Quantum Approximate Optimization Algorithm on Ising Problems
Asier Ozaeta, Wim van Dam, Peter L. McMahon
We report on the energy-expectation-value landscapes produced by the single-layer () Quantum Approximate Optimization Algorithm (QAOA) when being used to solve Ising problems.…
A Jacobi Diagonalization and Anderson Acceleration Algorithm For Variational Quantum Algorithm Parameter Optimization
Robert M. Parrish, Joseph T. Iosue, Asier Ozaeta +1
The optimization of circuit parameters of variational quantum algorithms such as the variational quantum eigensolver (VQE) or the quantum approximate optimization algorithm (QAOA)…
Decoherence of up to 8-qubit entangled states in a 16-qubit superconducting quantum processor
Asier Ozaeta, Peter L. McMahon
We report on the coherence of Greenberger-Horne-Zeilinger (GHZ) states comprised of up to 8 qubits in the IBM ibmqx5 16-qubit quantum processor. In particular, we evaluate the cohe…
Readiness of Quantum Optimization Machines for Industrial Applications
Alejandro Perdomo-Ortiz, Alexander Feldman, Asier Ozaeta +9
There have been multiple attempts to demonstrate that quantum annealing and, in particular, quantum annealing on quantum annealing machines, has the potential to outperform current…
Transport phenomena in superconducting hybrid nanostructures
A. Ozaeta
This PhD thesis is divided in 6 chapters. In chapter 1 we introduce basic superconducting phenomena. Such as, the BCS theory, the Andreev reflection and the proximity effect, and t…
Heat transport and electron cooling in ballistic normal-metal/spin-filter/superconductor junctions
Shiro Kawabata, Andrey S. Vasenko, Asier Ozaeta +2
We investigate electron cooling based on a clean normal-metal/spin-filter/superconductor junction. Due to the suppression of the Andreev reflection by the spin-filter effect, the c…
Huge thermoelectric effects in ferromagnet-superconductor junctions in the presence of a spin-splitting field
A. Ozaeta, P. Virtanen, F. S. Bergeret +1
We show that a huge thermoelectric effect can be observed by contacting a superconductor whose density of states is spin-split by a Zeeman field with a ferromagnet with a non-zero…
Efficient electron refrigeration using superconductor/spin-filter devices
Shiro Kawabata, Asier Ozaeta, Andrey S. Vasenko +2
Efficient electron-refrigeration based on a normal-metal/spin-filter/superconductor junction is proposed and demonstrated theoretically. The spin-filtering effect leads to values o…
Andreev current and subgap conductance of spin-valve SFF structures
A. S. Vasenko, A. Ozaeta, S. Kawabata +2
The Andreev current and the subgap conductance in a superconductor/ insulator/ ferromagnet (SIF) structure in the presence of a small spin-splitting field show novel interesting fe…
Electron cooling in diffusive normal metal - superconductor tunnel junctions with a spin-valve ferromagnetic interlayer
A. Ozaeta, A. S. Vasenko, F. W. J. Hekking +1
We investigate heat and charge transport through a diffusive SIF1F2N tunnel junction, where N (S) is a normal (superconducting) electrode, I is an insulator layer and F1,2 are two…
Andreev current enhancement and subgap conductance of superconducting hybrid structures in the presence of a small spin-splitting field
A. Ozaeta, A. S. Vasenko, F. W. J. Hekking +1
We investigate the subgap transport properties of a S-F-Ne structure. Here S (Ne) is a superconducting (normal) electrode, and F is either a ferromagnet or a normal wire in the pre…
Supercurrent and Andreev bound state dynamics in superconducting quantum point contacts under microwave irradiation
F. S. Bergeret, P. Virtanen, A. Ozaeta +2
We present here an extensive theoretical analysis of the supercurrent of a superconducting point contact of arbitrary transparency in the presence of a microwave field. Our study i…