I'm trying to build a quantum walk circuit. I have the C0 matrix as follows
import numpy as np
C0 = np.array([[-1, 0], [0, -1]])
As we can see, it's the (-)Identity matrix. How to build the -I matrix using quantum gates?
OPENQASM 2.0;
include "qelib1.inc";
gate unitary139793144506800 p0 {
u3(0,pi,pi) p0;
}
qreg q[2];
unitary139793144506800 q[0];
unitary139793144506800 q[1];
I obtained the above using qiskit unitary. Is there a way to decompose this into Pauli gates?