QUANTUM COMPUTER AND QUANTUM MEMORY

摘要

Disclosed is a quantum computer comprising a Pr3+ ion-doped crystal (20) comprising a host crystal meeting three conditions: condition 1 that the maximum phonon energy of the host crystal is so low that the uniform width of the 3F3(1) level of the Pr3+ ion by relaxation attributable to phonon emission is smaller than hyperfine splitting of the 3H4(1) level and 3F3(1) level of the Pr3+ ion, condition 2 that Pr3+ ion sites have no reversal symmetry, and the 3H4(1) level and the 3F3(1) level of the Pr3+ ion are a non-degenerate Stark level, and condition 3 that each atom in the host crystal does not have an electron spin. The quantum computer further comprises an optical resonator (21) that comprises the crystal (20) therein and has a resonator mode which is bound with transition between a hyperfine level which is one of 3H4(1) levels of the Pr3+ ion in the crystal and a hyperfine level which is one of 3F3(1) levels of the Pr3+ ion in the crystal, and a light source (10) that supplies a laser beam which resonates with the 3H4(1)-3F3(1) transition of the Pr3+ ion.