Recent content by qubits

What is antiferromagnetic/ferromagnetic coupling, and what is the difference between the two? I'm referring to coupling between two two-level half-flux quantum systems for example.

Look at the recent articles in Science and Nature by the guys (Wineland) from NIST and the guys in Austria. They did teleportation using ion trap quantum computing.

Is the potential operator (in positional/space basis) of the Hamiltonian always diagonal in that basis? And is the kinetic energy operator always diagonal in complementary momentum space?

Basically I want to write this in operator notation where I have defined the basis states. \hat{H} = \frac{1}{2m} \hat{p}_{1}^2 - \frac{1}{4 \pi \epsilon_0} \frac{Z e}{\hat{r}_{1} - R}

For the Schrödinger equation for a hydrogen atom, we need to write out: p^2/2m for the electron. If we define our basis states to be a linear discrete array of points, let's say 4 points. 0,d,2d, and 3d, where is some distance, on the order of a Bohr radius. How do I write p as an...

I don't know why NMR is even on there; it will never work past a few tens of qubits, and that's if they're lucky.

No, superconductor-based approaches would probably use niobium or, most likely, aluminium.