摘要 |
A refractive index changing apparatus includes a plurality of quantum dots (106) each having discrete energy levels including a ground level and an excited level, the excited level being higher than the ground level even if energy due to an ambient temperature is provided on the quantum dots, a barrier structure (106) formed of a dielectric which surrounds the quantum dots, means (105) for injecting an electron into a position of the ground level in each of the quantum dots via the barrier structure, utilizing a tunneling effect, or to prevent injection of an electron into the position, injecting the electron or preventing injection of the electron controlled by changing an energy level of the injection unit, means (101A) for emitting, to the quantum dots, a first light beam having first energy for exciting electrons from the ground level to the excited level, and means (101B) for emitting, to the quantum dots, a second light beam having second energy different from the first energy. |