Quantum process tomography with informational incomplete data of twoJ-coupled heterogeneous spins relaxation in a time window much greater thanT₁

Abstract

We reconstruct the time dependent quantum map corresponding to the relaxation process of a twospin system in liquid-state NMR at room temperature. By means of quantum tomography techniques that handle informational incomplete data, we show how to properly post-process and normalize the measurements data for the simulation of quantum information processing, overcoming the unknown number of molecules prepared in a non-equilibrium magnetization state (N j ) by an initial sequence of radiofrequency pulses. From the reconstructed quantum map, we infer both longitudinal (T 1 ) and transversal (T 2 ) relaxation times, and introduce the J-coupling relaxation times (T T , J J 1 2 ), which are relevant for quantum information processing simulations. We show that the map associated to the relaxation process cannot be assumed approximated unital and trace-preserving for times greater than T . J 2 OPEN ACCESS RECEIVED

Optimal and robust experiment design for quantum state tomography of star-topology register

“…Besides, due to the readout operations generated by PQCs are flexible to be adjusted, they can be further optimized according to the specific experimental conditions, such as measurement noise [38], control errors [39,40] and relaxation effect [41]. Our work also has potential applications in multiparameter quantum metrology [42], quantum enhanced imaging [43,44] and various quantum-process-tomography experiments [45][46][47][48].…”

Characterizing quantum instruments: from non-demolition measurements to quantum error correction

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True experimental reconstruction of quantum states and processes via convex optimization

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