Quantum circuit T-depth reduction method and apparatus
View Patent ↗Disclosed herein method and apparatus for reducing a T-depth. According to an embodiment of the present disclosure, there is provided a quantum circuit T-depth reduction method comprising: receiving a quantum circuit including two Toffoli gates and a first quantum circuit between the two Toffoli gates; adding a pair of first control P gate and second control P gate to the quantum circuit; and swapping the first quantum circuit and any one of the first control P gate and the second control P gate such that the first quantum circuit is disposed between the first control P gate and the second control P gate.
1 . A quantum circuit T-depth reduction method comprising:
receiving a quantum circuit including two Toffoli gates and a first quantum circuit between the two Toffoli gates;
adding a pair of first control P gate and second control P gate to the quantum circuit; and
swapping the first quantum circuit and any one of the first control P gate and the second control P gate such that the first quantum circuit is disposed between the first control P gate and the second control P gate.
2 . The quantum circuit T-depth reduction method of claim 1 , further comprising determining whether the first quantum circuit and the control P gate are swappable,
wherein the swapping comprises swapping the first quantum circuit and the any one control P gate when the first quantum circuit and the control P gate are swappable.
3 . The quantum circuit T-depth reduction method of claim 2 , wherein the determining comprises that the first quantum circuit and the any one control P gate are swappable, when a phase when passing through the any one control P gate and the first quantum circuit and a phase when passing through the first quantum circuit and the any one control P gate after the any one control P gate and the first quantum circuit are swapped are the same.
4 . The quantum circuit T-depth reduction method of claim 2 , wherein the determining comprises:
removing a X gate, H gate and R z gate of the first quantum circuit; and
determining that the first quantum circuit and the any one control P gate are swappable, when a control portion of a control NOT gate of the first quantum circuit, from which the X gate, H gate and R z gate are removed, is located on any one of two lines of the any one control P gate and a target portion is located on a third line.
5 . The quantum circuit T-depth reduction method of claim 4 , wherein the removing comprises removing all H gates located on two lines of the any one control P gate and removing all R z gates present in the first quantum circuit, after removing the X gate from the first quantum circuit through X gate propagation.
6 . The quantum circuit T-depth reduction method of claim 1 , further comprising converting the first quantum circuit into a second quantum circuit corresponding to a function of the first quantum circuit, when the first quantum circuit and the any one control P gate are swapped.
7 . The quantum circuit T-depth reduction method of claim 1 , wherein the adding comprises adding a pair of first control P gate and second control P gate in consideration of a control portion and target portion of the Toffoli gate.
8 . The quantum circuit T-depth reduction method of claim 1 , wherein the adding comprises adding a control P gate and a control P† gate to the quantum circuit.
9 . A quantum circuit T-depth reduction method comprising:
adding a control P gate and a control P† gate to a quantum circuit including two Toffoli gates and a first quantum circuit between the two Toffoli gates;
determining whether the first quantum circuit and any one of the control P gate and the control P† gate are swappable;
swapping the first quantum circuit and any one gate when the first quantum circuit and any one gate are swappable.
10 . The quantum circuit T-depth reduction method of claim 9 , wherein the determining comprises:
removing a X gate, H gate and R z gate of the first quantum circuit; and
determining that the first quantum circuit and the any one gate are swappable, when a control portion of a control NOT gate of the first quantum circuit, from which the X gate, H gate and R z gate are removed, is located on any one of two lines of the any one gate and a target portion is located on a third line.
11 . The quantum circuit T-depth reduction method of claim 10 , wherein the removing comprises removing all H gates located on two lines of the any one gate and removing all R z gates present in the first quantum circuit after removing the X gate from the first quantum circuit through X gate propagation.
12 . The quantum circuit T-depth reduction method of claim 9 , further comprising converting the first quantum circuit into a second quantum circuit corresponding to a function of the first quantum circuit when the first quantum circuit and the any one gate are swapped.
13 . A quantum circuit T-depth reduction apparatus comprising:
a receiving unit configured to receive a quantum circuit including two Toffoli gates and a first quantum circuit between the two Toffoli gates;
an adding unit configured to add a pair of first control P gate and second control P gate to the quantum circuit; and
an swap unit configured to swap the first quantum circuit and any one of the first control P gate and the second control P gate such that the first quantum circuit is disposed between the first control P gate and the second control P gate.
14 . The quantum circuit T-depth reduction apparatus of claim 13 , further comprising a determination unit configured to determine whether the first quantum circuit and the control P gate are swappable,
wherein the adding unit adds the pair of first control P gate and second control P gate when the first quantum circuit and the control P gate are swappable.
15 . The quantum circuit T-depth reduction apparatus of claim 14 , wherein the determination unit determines that the first quantum circuit and the any one control P gate are swappable when a phase when passing through the any one control P gate and the first quantum circuit and a phase when passing through the first quantum circuit and the any one control P gate after the any one control P gate and the first quantum circuit are swapped are the same.
16 . The quantum circuit T-depth reduction apparatus of claim 14 , wherein the determination unit removes a X gate, H gate and R z gate of the first quantum circuit and determines that the first quantum circuit and the any one control P gate are swappable when a control portion of a control NOT gate of the first quantum circuit, from which the X gate, H gate and R z gate are removed, is located on any one of two lines of the any one control P gate and a target portion is located on a third line.
17 . The quantum circuit T-depth reduction apparatus of claim 16 , wherein the determination unit removes all H gates located on two lines of the any one control P gate and removes all R z gate present in the first quantum circuit, after removing the X gate from the first quantum circuit through X gate propagation.
18 . The quantum circuit T-depth reduction apparatus of claim 13 , further comprising a converting unit configured to convert the first quantum circuit into a second quantum circuit corresponding to a function of the first quantum circuit, when the first quantum circuit and the any one control P gate are swapped.
19 . The quantum circuit T-depth reduction apparatus of claim 13 , wherein the adding unit adds a pair of first control P gate and second control P gate in consideration of a control portion and target portion of the Toffoli gate.
20 . The quantum circuit T-depth reduction apparatus of claim 13 , wherein the adding unit adds a control P gate and a control P† gate to the quantum circuit.