Patent ID: 8106717

Claim:
A quantum gate method comprising: causing a common resonator mode to resonate with a first transition between states of |2> i and |3> i in regard to physical systems i (1≦i≦n, n: integer not less than 2), the states of |2> i and |3> i being coupled to each other by the first transition having a homogenous broadening of ΔE homo greater than an energy difference between two states of |0> i and |1> i , an energy difference between the states of |2> i and |3> i being greater than the homogenous broadening of ΔE homo , a plurality of physical systems contained in a resonator being set as the physical systems i, quantum bits being represented by the two states of |0> i and |1> i of each of the physical systems i; transferring states of m (2≦m≦n) quantum bits represented by states of |0> k and |1> k to states of |4> k and |5> k , respectively, when a quantum bit gate operation using the common resonator mode is executed between the quantum bits represented by m physical systems k (k=j(1), j(2), . . . , j(m)) included in the physical systems i, the states of |4> k and |5> k being two states of each of the physical systems k, an energy difference between the states of |4> k and |5> k being greater than the homogenous broadening of ΔE homo , an energy difference between any one of the two states of |4> k and |5> k and any one of states of |2> k and |3> k being greater than the homogenous broadening ΔE homo (|E(|u> k )−E(|v> k )|>ΔE homo , u, vε{2, 3, 4, 5}, u≠v, E(|s>) representing energy of a state s); executing adiabatic passage between the physical systems k, using light that resonates with a second transition between states of |3> k and |4> k and a third transition between states of |3> k and |5> k ; executing, between the quantum bits, a quantum bit gate operation using the common resonator mode; and transferring, to the states of |0> k and |1> k , the states of quantum bits represented by the states of |4> k and |5> k , respectively.