Quantum-information processing under the auspices of the scattering-matrix formalism

• Grant number: 18/00796-3
• Support Opportunities: Regular Research Grants
• Start date: June 01, 2018
• End date: May 31, 2020
• Field of knowledge: Physical Sciences and Mathematics - Physics - Atomic and Molecular Physics
• Principal Investigator: Reginaldo de Jesus Napolitano
• Grantee: Reginaldo de Jesus Napolitano
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

We will approach a unified theory of quantum information and scattering. We willinvestigate three collisional aspects: the preparation of an entrance asymptotic state, the timeevolution from the initial wave packet under the collisional interaction, and the post-selectionand detection of the exit asymptotic state. From the informational viewpoint, we have alreadyformulated the generalized-continuous-dynamical-decoupling (GCDD) method and will studyit systematically. As expected results, we will answer these questions: In what circumstancesis the GCDD method effective? Could it be made more efficient? If it could, how? Is itpossible to build a logical qudit, protected against environmental noise, using real atoms and/ormolecules together with control fields? How can we describe weak measurements using theformal theory of quantum scattering? How to use the scattering-matrix formalism when wehave a strong interaction, as in the case of a quantum logical operation, and a weak interaction,as in the case of environmental noise? For a diatomic system, in the presence of external fields,how to describe the momentum distribution of the system and the corresponding exchange ofmomentum, angular momentum, and energy with the environment? Could we, for example,with control fields, decelerate the system using its internal-state multiplicity? To answer thesequestions, we will face scientific and technological challenges that we will overcome by: (1)simulating the application of the GCDD method to qudits; (2) recalculating the results of theoriginal article on weak measurements under the point of view of the S-matrix formalism;and (3) applying the split-operator method to obtain the translational dynamics of a molecularsystem under the action of external fields. (AU)

Scientific publications

(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)

NAPOLITANO, REGINALDO DE JESUS; FANCHINI, FELIPE FERNANDES; DA SILVA, ADONAI HILARIO; BELLOMO, BRUNO. Protecting operations on qudits from noise by continuous dynamical decoupling. PHYSICAL REVIEW RESEARCH, v. 3, n. 1, MAR 12 2021. (18/00796-3, 19/05445-7)

BRASIL, CARLOS ALEXANDRE; MOUSSA, MILED HASSAN YOUSSEF; NAPOLITANO, REGINALDO DE JESUS. Phase-retrieval from Bohm's equations. EUROPEAN PHYSICAL JOURNAL PLUS, v. 135, n. 12, DEC 1 2020. (18/00796-3)

DE CASTRO, LEONARDO ANDRETA; BRASIL, CARLOS ALEXANDRE; NAPOLITANO, REGINALDO DE JESUS. Weak values in collision theory. ANNALS OF PHYSICS, v. 392, p. 272-286, MAY 2018. (18/00796-3, 11/19848-4)