Kvanttifaasit

Kvanttifaasit refers to the phenomenon of phase transitions occurring at the quantum level, distinct from classical phase transitions driven by thermal energy. In quantum phase transitions, the transition is driven by quantum fluctuations, typically as a control parameter, such as pressure or magnetic field, is tuned to absolute zero temperature. These transitions involve a change in the ground state of a system.

At finite temperatures, thermal fluctuations disrupt the ordered state, leading to a transition to a disordered state. In contrast, at absolute zero, thermal fluctuations are absent. Quantum fluctuations, arising from the Heisenberg uncertainty principle, become dominant and can drive the system into a different ground state. This often involves changes in the symmetry of the system.

Examples of systems exhibiting quantum phase transitions include magnetic materials, superconductors, and superfluids. For instance, in certain magnetic materials, applying a magnetic field can suppress magnetic ordering, leading to a quantum phase transition to a non-magnetic state. Similarly, in superconductors, pressure can tune the system through a quantum critical point, affecting its superconducting properties. The study of quantum phase transitions is crucial for understanding the behavior of matter at low temperatures and exploring exotic quantum phenomena.