Zhe Feng

Introduction

Feng Zhe received his Bachelor of Engineering in Space Science and Technology from Nanjing University of Aeronautics and Astronautics in 2014. He once lead an Undergraduate Innovation Fund Project under Prof. LI Jin Bin on understanding the mechanisms of phase transition and negative pressure. After graduating from NUAA, he started his PhD under the supervision of Prof. C H Woo this September.

Education Experience

Ph.D. Candidate	2014-	Department of Physics and Materials Science, City University of Hong Kong
Bachelor of Engineering	2010-2014	Space Science and Technology, Nanjing University of Aeronautics and Astronautics

On going projects

Magnetic induced anharmonic effects on the thermodynamics of Amorphous iron, the relation between ferromagnetism and microstructure, and the associated thermodynamic, mechanical, magnetic properties.

Basic knowledge and skill required to finish Ph.D. degree

* Basic Knowledge

1. Theoretical Mechanics.

    Lagrange mechanics, and Hamiltonian mechanics. Ask Lu to collect the book to get this knowledge.

2. Magnetism

   A. fundamental kinds of magnetism in condensed matters: To get a general picture.
      Diamagnetism; 
      Paramagnetism; 
      Ferromagnetism: ferromagnetic order; anti-ferromagnetic order, ferrimagnetism
      Non-linear magnetic structure.

   B. Quantum theory of magnetism. Able to familiar with the deduction and get a clear physical picture.
      Heisenberg Model
      RKKY model for indirect exchange interaction
      Spin wave theory
      Molecule field approximation
      Ferro/para-magnetic phase transition
      Itinerant magnetic theory

   C. Ferromagnetic crystal and magnetic domain structure
      Exchange interaction energy, external field energy; demagnetizing energy
      Magnetic anisotropy
      Magnetic induce thermal expansion
      Single domain magnetic particle
      Super-paramagnetism

   D. Magnetization Process
      Hysteresis loop; coercivity;
      
   Reference:
   1. Chinese Version. 《凝聚态磁性物理》 姜寿亭，李卫编著； 科学出版社。
   2. Peter Mohn, Magnetism in the Solid State: An Introduction. 
   

3. Spin Lattice Dynamics

   A. Basic Knowledge about atomistic simulations
      Density function theory
      Molecular Dynamics simulation
      Monte Carlo simulation
      Phase field model
   Get to know the fundamental algorithm about the above methods, and tell the relation of them.

   B. Learn Detail of molecular dynamics
      a. Write a basic flow chat of MD
      b. Interatomic potentials used, like Lennard-Jones, EAM. Learn to generate a potential table.
      c. How to integrate the equation of motion. velocity-verlet, leap-frog, and so on.
      d. Thermostat. rescaling; Breathing; Nose-Hoover; Langevin
      e. Barostat. extended method; constaint method.

   C. Calculation of basic thermodynamic quantities from MD
      a. Energy; volume; heat capacity
      b. Virial Pressure (or stress)
      c. Time correlation function
      d. Histogram

4. C++ programming

   A. Basic instruction simple arithmetic expression;
   B. class (or structure), array and pointer
   D. Pre-assembly, or Macro assembly
   C. parallel programming: OpenMP, CUDA

5. Solid-State theory

   A. Stucture of Solid Matter
      Crystal lattice; Reciprocal space; Defect in Solid;
      Brillouin Zones;

   B. Atomic vibtrations in solid
      Simple harmonic Potential; single-atomic or disatomic linear atom chain; 
      phonon; density of state; dispersion relation;
      Thermal energy, heat capacity of harmoinc solid
      Effects due to anharmonicity: thermal expansion, heat conduction

   C. Electrons in solids
      Inifinte square-well potential
      Fermi statistics
      Heat capacity of electrons in solids
      Band-structure
      Tight-binding approximation
      Density of states     

   D. Elastic properties.
      Strain-stress relation

6. Other related background

   A. Quantum mechanics
      a. Schordinger picture
      b. Heisenberg picture
      c. Path integration picture
      d. Spin operator

   B. Statistcal thermodynamics
      a. ensemble theory; Boltzmann most probability theory.
      b. 0th, 1st, 2nd thermodynamic law
      d. thermodynamic function, Maxwell relation.
      c. fluctuation theory
      d. transition theory

   C. Electrodynamics
      Maxwell equations
      Green function

   D. Mathematical method
      a. Fast Fourier transform
      b. numerical method in solving ordinary differential equations; finite differential method
      c. Gaussian integration; 
      d. Residue theorem
      d. optimization method: steepest descent method; conjugated gradient method; Nudge elastic band;
      

* Software

   1. Word processing: Micro-office
   2. Data processing; Origin; Matlab;
   3. Visualized: Origin; Matlab; Atomeye; gnuplot;
   4. Bash script in Linux.

* Literature review

   1. About magnetism
   2. About Amorphous structure
   3. About magneto-caloric, magneto-mechanical, magneto-thermal
   Requirement: One review paper weekly at least.

Class schedule

Monday	Tuesday	Thursday
09:00-10:50 AP8002	10:00-11:50 SG8001	10:00-11:50 SG8001
19:00-21:50 AP8302 & AP8004

Contact

Office:	AC1 - G1417
Email:	zhefeng2-c@my.cityu.edu.hk
Tel:	+(852)-5340-4465