You may have already heard that qubits do not preserve their state or information indefinitely. Often the environment causes the qubit to decohere (see the video about (de)coherence). Another way for a qubit to lose its information is through relaxation, a concept that Ph.D. student Jonas Helsen (QuTech) will introduce in the video below.
Suppose that you have full control over your system and on the architecture behind your quantum states. What should you change about the two quantum states for a single qubit to increase your relaxation time to infinity?
If you want an extensive insight on quantum relaxation, take a look at the chapter Quantum Theory of Relaxation (Density Matrix Theory and Applications, Blum K., 1996). This is an excellent way to dive into the subject.
- Blum K. (1996) Quantum Theory of Relaxation. In: Density Matrix Theory and Applications. Physics of Atoms and Molecules. Springer, Boston, MA