Sabre Kais Group

Quantum Information and Quantum Computation

Finite Size Scaling Method for Quantum Critical Phenomena and Stability of Atomic and Molecular Systems

The study of quantum phase transitions, which are driven by quantum fluctuations as a consequence of Heisenberg's uncertainty principle, continues to be of increasing interest in the field of atomic and molecular physics. This is motivated by the recent experimental searches for the smallest stable multiply charged anions, experimental and theoretical work on the stability of atoms and molecules in external electric and magnetic fields, design and control electronic properties of materials using quantum dots, study of selectively breaking chemical bonds in polyatomic molecules and phase transitions of finite clusters. 

In this field we have established an analogy between symmetry breaking of electronic structure configurations and quantum phase transitions. Furthermore we have developed the finite size scaling method for quantum systems. In this case, the finite size corresponds not to the spatial dimension but to the number of elements in a complete basis set used to expand the exact wave function of a given Hamiltonian.