# Quantum Deutsch Problem

1. Oct 25, 2009

### Kreizhn

1. The problem statement, all variables and given/known data
In a quantum information setting:

I'm given a function $f: \{0,1\} \to \{0,1\}$ and my goal is to construct a quantum circuit that constructs the two qubit gate
[tex] \frac1{\sqrt3} \left( (-1)^{f(0)}|00\rangle + (-1)^{f(1)} | 01 \rangle + |11\rangle \right) [/itex]

3. The attempt at a solution
The goal of this problem is to find a quantum algorithm that computes a variation of Deutsch's problem. I've tried the standard techniques of applying Hadamards to a target and control qubit and then queuring f. I've tried fourier transforms, Toffoli gates, everything, but I can't see how to construct this state. Any help would be much appreciated.