Magnetic-field-driven transitions of chaotic dynamics in quantum cavities

The influence of a magnetic field on the classical dynamics in ballistic cavities is investigated by analyzing conductance fluctuations that result from quantum interference effects. The magnetic field transforms the exponential decay of the probability distributions of the dwell time and the enclosed area to a power-law decay. The conductance fluctuations correspondingly exhibit a transition from a nonfractal to a fractal behavior. We also identify two additional states that take place when the magnetic field is weaker or stronger than that required to achieve the power-law probability distributions.