Quasi-exact quantum computation

Understand

We study quasi-exact quantum error correcting codes and quantum computation with them.

• A quasi-exact code is an approximate code such that it contains a finite number of scaling parameters, the tuning of which can flow it to corresponding exact codes, serving as its fixed points.
• The computation with a quasi-exact code cannot realize any logical gate to arbitrary accuracy.
• To overcome this, the notion of quasi-exact universality is proposed, which makes quasi-exact quantum computation a feasible model especially for executing moderate-size algorithms.