+1 vote
asked by (140 points)

Hi Miles,

we would like to use the GateTevol method with swap gates for spinful fermions and run into trouble with the anticommutation of the C-operators. Are there already working solutions to this problem or do we have to come up with our own. Are there any solutions you would be suggesting?

1 Answer

+1 vote
answered by (70.1k points)

Hi good question, we are working on a more automatic system to make working with fermions easier. However, it might be the end of this summer at best before it's put in and fully tested.

In the meantime, using swap gates with fermionic operators should work well as long as you define fermionic swap gates. As you may know, these are like usual swap gates, except they include a minus sign when the swap operation swaps two sites that are both in fermion-parity-odd states.

If you do proceed with this route, you could test your code by using the AutoMPO system to help you out, because AutoMPO does handle fermion signs automatically and the toExpH function lets you approximately exponentiate a Hamiltonian defined via AutoMPO.

commented by (140 points)
Thank you very much. It's working now.
commented by (70.1k points)
Great, thanks for letting me know
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