Quantum phases of out of equilibrium systems in quantum information problems

• Grant number: 14/26356-9
• Support Opportunities: Regular Research Grants
• Start date: April 01, 2015
• End date: March 31, 2017
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Eduardo Peres Novais de Sá
• Grantee: Eduardo Peres Novais de Sá
• Host Institution: Centro de Ciências Naturais e Humanas (CCNH). Universidade Federal do ABC (UFABC). Santo André , SP, Brazil
• City of the host institution: Santo André

Abstract

The present project has two different and complementary parts in order to explore the relation between decoherence and out of equilibrium systems used for quantum information processing. 1) In its first part the project explores the physics of systems out of equilibrium, with special emphasis in quantum computers with a large number of degrees of freedom. Specifically, I will study quantum memories protected by topological quantum error correction codes. 2) The second part of the project complements the first part by studying the physics of a single qubit out of equilibrium in the presence of decoherence sources. More specifically, I will consider the problem of quantum dots coupled to reservoirs in a dissipative environment simulated by quantum fluctuations on the circuit. Albeit a simple model, it will serve as a starting point to the understanding of decoherence due to fluctuations on qubit fields control. The project has the following specific aims:Aim 1.1: determine the quantum error threshold for a topological quantum error correction code (the surface code) in the presence of correlated errors for many error correction cycles.Aim 2.1: study a quantum dot coupled to two terminals in the presence of a noise circuit.Aim 2.2: study a double quantum dot coupled to two terminals in the presence of a noise circuit. (AU)

Scientific publications

(6)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

LOPEZ-DELGADO, D. A.; NOVAIS, E.; MUCCIOLO, E. R.; CALDEIRA, A. O.. Long-time efficacy of the surface code in the presence of a super-Ohmic environment. Physical Review A, v. 95, n. 6, JUN 23 2017. (14/26356-9)

NOVAIS, E.; STANFORTH, A. J.; MUCCIOLO, EDUARDO R.. Surface code fidelity at finite temperatures. Physical Review A, v. 95, n. 4, APR 26 2017. (14/26356-9)

ZHANG, GU; NOVAIS, E.; BARANGER, HAROLD U.. Rescuing a Quantum Phase Transition with Quantum Noise. Physical Review Letters, v. 118, n. 5, FEB 2 2017. (14/26356-9)

NOVAIS, E.; STANFORTH, A. J.; MUCCIOLO, EDUARDO R.. Surface code fidelity at finite temperatures. PHYSICAL REVIEW A, v. 95, n. 4, p. 14-pg., 2017-04-26. (14/26356-9)

LOPEZ-DELGADO, D. A.; NOVAIS, E.; MUCCIOLO, E. R.; CALDEIRA, A. O.. Long-time efficacy of the surface code in the presence of a super-Ohmic environment. PHYSICAL REVIEW A, v. 95, n. 6, p. 8-pg., 2017-06-23. (14/26356-9)

ZHANG, GU; NOVAIS, E.; BARANGER, HAROLD U.. Conductance of a dissipative quantum dot: Nonequilibrium crossover near a non-Fermi-liquid quantum critical point. Physical Review B, v. 104, n. 16, OCT 25 2021. (14/26356-9)