Curriculum Vitae (August 1998)
Name:                 Rogério Costa Reis de Sousa
Date of Birth:     November 1st, 1974
Place of Birth:    Belo Horizonte - State of Minas Gerais - BRAZIL
E-Mail:               rsousa@physics.umd.edu
Address (Mail): 4303 Rowalt Dr. apt 201 - College Park, MD - USA - 20740
Family Address: Rua Bernardo Figueiredo 104/ap301 - Serra - Belo Horizonte - MG - 30220-140 - BRASIL
 
Education

Phd:                                Current enrolled as a Full time Teaching assistant at the University of Maryland at College Park, MD - USA - Started August 1998
                                        Will take Phd Qualifying Exam by August 99.

Master's degree:           Master program at the "Institute of Physics Gleb Wathaghin" at  State University of Campinas (Unicamp) - March 1997 - July 1998

Undergraduate course:  Bachelor in Physics - State University of Campinas (Unicamp) - Campinas - SP
                                        March 1993 to December 1996

High School - 4th year:  Mineola High School - Mineola, Texas, USA - August 1991 to June 1992 - (Received a High School diploma)
(Corresponds to the 3rd year in Brazil) 

High School - 1st and 2nd years: Colégio Santo Antônio - Belo Horizonte - MG - February 1990 to June 1991
 

 
Work Experience

Current Work:    Full time Teaching Assistant for PHYS 262 (General Physics: Vibrations, Waves, Heat, Electricity and Magnetism)
Period:                 August 98 - December 21
Description:        Office hours, Grading exams, lecture homeworks and tutorial homeworks; assisting students during tutorial sessions. About 20 hours a week.

Type of Work:     Teaching Assistant
Period:                 August 1997 - December 1997
Description:         Part Time work - about 12 hours a week - Grading
                             assignments, tests and giving problem solving lectures twice a
                             month.

 

Scholarships - Research Projects
 
"Study of the metal-insulator transition of the t-J model using the variational principle"

Project advisor:  Prof. G. G. Cabrera - Department of Condensed Matter Physics
                            Institute of Physics - Unicamp
Period:                Started on march 1997 - To be finished by July 1998
Funding:              Funded by CNPq as a Master at Sciences project grant.

Abstract

This project will lead to a Master at Sciences degree at State University of Campinas (Unicamp) and consists basically of the generalization of Prof. G.G. Cabrera et al article "Interplay of Holon and Spinon dynamics on doped anisotropic Heisenberg chains" (Solid State Commun. 88, 33, 1993). There we find a mean field model of the metal-insulator transition of a one dimensional Heisenberg lattice doped with holes. They use a variational wave function based on the Bethe Ansatz solution; in our work we plan to treat the two dimensional case using a variational wave function with a spiral spin density. This choice is based on neutron scattering experiments that determine the magnetic order of High Tc materials near the critical temperature. We plan to use this model to describe the metal-insulator transition (and perhaps the metal-superconductor transition) that occurs in the reference compounds of the High Tc materials (Copper oxides) when we dope them. We plan to make a phase diagram (with d , the hole density on an axis and J the magnetic interaction magnitude on the other) showing the metal and insulator regions.

"Finite Clusters in Statistical Mechanics"

Project advisor:  Prof. G. G. Cabrera - Department of Condensed Matter Physics
                            Institute of Physics - Unicamp
Period:                November 1995 to February 1997
Funding:             Funded by FAPESP as a Scientific Initiation Project

Abstract

The objective of this work is to analyse the frustration on the triangular Ising lattice (Antiferromagnetic case) at T = 0. Using the Kikuchi method (Cluster variational method) we showed that a pair probability aproximation (of the Bethe-Peierls type) applied to the triangular lattice divided in three sublatices is sufficient to show that the magnet is disordered at all temperatures (This result is yet to be published).
In the second part of the project we studied the analogy between classical Statistical Mechanical systems and Quantum Spin models. The main reference used was the review article of J. B. Kogut, "An introduction lattice gauge theory and Spin Systems" (Rev. Mod. Phys. 51, 659, 1979).

 
"Monte Carlo Method applied to the 2d and 3d Ising Model"

Project advisor:  Prof. G. G. Cabrera - Department of Condensed Matter Physics
                            Institute of Physics - Unicamp
Period:                June - July 1996
Funding:             Undergraduate research project - Not funded

 

Abstract

Here we made Monte Carlo simulations using the Metropolis algorithm to obtain precise graphs of the spontanious magnetization versus temperature of finite spin clusters in a bidimensional square lattice (Ferromagnetic Ising model) and a tridimensional cubic one (20X20X20 Spins). In the case of the square lattice we compared our result with Onsager´s exact solution, noting that a finite cluster has the magnetization rounded near the critical temperature. In the case of the cubic lattice we obtained a rather precise estimate for the critical temperature: Tc = (4.4 ± 0.2) J/K .

 
"Mathematical Methods in Statistical Mechanics"

Project advisor:   Prof. Hugo H. Torriani - Department of Mathematics - Unicamp
Period:                 August 1994 to July 1995

Funding:               Funded by CNPq as a Scientific Initiation Scholarship

Abstract

In this project I was initiated at the empirical basis of Statistical Mechanics by the elementary books like "Statistical Physics" of F. Reif (Berkeley Physics Course, vol 5, Mc Graw Hill, NY, 1967). This study was complemented by advanced topics like the Ising Model in one and two dimensions (We used the book "Statistical Mechanics" from Kerson Huang). Then we made a detailed study of the first five chapters of C. J. Thompson´s book "Mathematical Statistical Mechanics", Princeton University Press, Princeton, NJ, 1972. This constituted a reasonable introduction to Statistical Mechanics from the Mathematical point of view.

 

Summer and Winter Courses

Summer Course:  Expositive lectures about the research areas of the Institute of
                              Theoretical Physics - IFT - Unesp - São Paulo - Brazil
                              January 20-24, 1997

Winter Course:    Expositive lectures about the research areas of the Department of
                              Physics of the Federal University of Minas Gerais - UFMG - Belo
                              Horizonte - Brazil - July 8-12, 1996

Summer Course:   Introduction to the Theory of Probability
(Funded by CNPq)Institute of Pure and Applied Mathematics - IMPA
                               Rio de Janeiro - Brazil - January to February 1995

 

 

 

 

Congresses attended and Works presented

 

 

"Mathematical Methods in Statistical Mechanics"
Presented in the III Internal Congress of Scientific Initiation - State University of Campinas (Unicamp) - Brazil - August 28 to September 1st - 1995
 
"Monte Carlo Method applied to the 2d and 3d Ising Model"
Presented at the Panel exhibition - Department of Physics - Unicamp - July 5 - 1996