Two-qubit pure state tomography by five product orthonormal bases<xref rid="cpb_27_10_100306_fn1" ref-type="fn">*</xref><fn id="cpb_27_10_100306_fn1"><label>*</label><p>Project supported partially by the National Key Research and Development Program of China (Grant No. 2016YFB1000902), the National Natural Science Foundation of China (Grant No. 61472412), and the Program for Creative Research Group of the National Natural Science Foundation of China (Grant No. 61621003).</p></fn>

Two-qubit pure state tomography by five product orthonormal bases**

Project supported partially by the National Key Research and Development Program of China (Grant No. 2016YFB1000902), the National Natural Science Foundation of China (Grant No. 61472412), and the Program for Creative Research Group of the National Natural Science Foundation of China (Grant No. 61621003).

Wang Yu^{1, 2}, Shang Yun^{1, 2, 3, 4, †}

Simulation of swap operation. The swap operation is: |00⟩⟨00| + |10⟩⟨ 01| + |01⟩⟨10| + |11⟩⟨11|. If we take the swap operation on input state |jk⟩, the output state will be |kj⟩, j, k = 0, 1. It can be decomposed into three control-not operations. The bases states of and would be transformed into the bases states of and by this operation.