# Tag Info

Accepted

### How does magic state distillation overhead scale compare to quantum advantages?

In the context of scalable quantum computing, the polylog scaling needed for magic state distillation should not be a problem. Indeed, it is not the only polylog scaling we need to contend with. ...
Accepted

### Injecting arbitrary rotations into the surface code

Generally speaking, you would never do a $\pi/2^{10}$ rotation by physical injection and distillation. It would be horrendously expensive. It's far cheaper to use a series of T and H gates to ...
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### Good references to learn magic state distillation for fault tolerance

Disclaimer: these links do not all fit the criterion recent. First and foremost, it is important to realize that there is no 'one' magic state, and no 'one' magic state distillation. The term 'magic ...
Accepted

### 15-to-1 distillation protocol: why is the probability of error of the distilled state $35p^3$ and not $\binom{15}{3} p^3=455p^3$?

It's because not every triplet is a failure. Most are detected. A basic error is for one of the T gates to instead be Z*T. There are 15 T gates. Each of the 15 possible basic errors has a unique ...
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### Why is $\rho$ NPT if and only if $\rho^{\otimes N}$ is NPT?

The short answer is that $(\rho^{\otimes N})^{T_B}=(\rho^{T_B})^{\otimes N}$. More explicitly, if $\rho=\sum_{ii'jj'}\rho_{ii',jj'}|i\rangle\!\langle i'|\otimes |j\rangle\!\langle j'|$, then we can ...
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### Motivation for the definition of k-distillability

Remember that the partial transpose condition is generally good for detecting entanglement, i.e. a bipartite state $\rho$ is certainly entangled if the partial transpose is not non-negative. In other ...
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### What do entanglement cost and distillable entanglement have to do with measuring entanglement?

The entanglement entropy (what you call "von Neumann entropy") is a good measure for entanglement of pure states in the asymptotic setting, i.e. when one is dealing with many copies. However, it is ...
Accepted

### Entanglement distillation by local operations and post-selection using one entanglement pair

There are two different contexts where the term "entanglement distillation" is used, and are largely incomparable, even if they are conceptually extremely close (and I'm sure you'll be able to find ...