Quantum chaos, decoherence and quantum computation

Quantum chaos [1,2] has faced over the years problems of increasing complexity, from simple toy models like the kicked rotator to single-particle physics (hydrogen atoms in strong magnetic and/or microwave fields, cold atoms in laser fields, quantum transport in disordered lattices) and to many-body interacting systems [3] such as nuclei, complex atoms, quantum dots, quantum spin glasses and, more recently, quantum computers. In fact, a quantum computer represents a complex system of many coupled qubits, which in general can be viewed as a many-body interacting quantum system. Problems such as the transition to chaos and the thermalization border were studied also for the quantum computer. On the other hand, typical problems in the field of quantum chaos, such as the stability of quantum motion, decoherence and the quantum-to-classical transition, are also essential for any realistic implementation of a quantum computer.