Standard Quantum Process Tomography
SQPT approaches this using linearly independent inputs, where is the dimension of the Hilbert space . For each of these input states, sending it through the process gives an output state which can be written as a linear combination of the, i.e. . By sending each through many times, quantum state tomography can be used to determine the coefficients experimentally.
Write
- ,
where is a matrix of coefficients. Then
- .
Since form a linearly independent basis,
- .
Inverting gives :
- .
Read more about this topic: Quantum Tomography, Quantum Process Tomography
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