How can we "isolate" a qubit

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From Wikipedia : In ion quantum computer, if the ions are not properly isolated, noise can result from ions interacting with external electromagnetic fields, which creates random movement and destroys the quantized energy states.
This statement also appeared on DiVincenzo's criteria for building quantum computer albeit in different terms, that is condition of long decoherence time.
But in nature, a description of quantum state need the inclusion of environment. Which means we need to include interaction and bath Hamiltonian to the whole system. These Hamiltonian can lead to decoherence or dissipation of quantum computing resource (superposition or entanglement).
From these knowledge, intuitively, to build a working quantum computer we need active measure to isolate a qubit from the surrounding environment. Isolation in this context only mean from the environment, qubit can still be entangled with one another or quantumly correlated.
Back on the question on hand ? How can we or what method/technology used in constructing quantum computer today to achieve this ?

Roger Vadim · Accepted Answer

One cannot absolutely isolate a qubit from its environment, but one can do it to a good enough degree/approximation to perform quantum computation. Loss&DiVincenzo discuss it in many details for the electron spins in quantum dots, just like other QM proposals (for nuclear spins, for ions, for Josephson junctions, etc.)
This typically involves lowering a temperature, limiting interactions with the environment (e.g., isolating a few ions in an ion trap or having just one electron spin in a QD), tuning the interactions out of resonance, and performing manipulations adiabatically slowly.

How can we "isolate" a qubit

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