Beam steering apparatus and system including the same

1. A beam steering apparatus comprising:

a substrate;

at least one light source provided on the substrate;

a first waveguide configured to transmit a first light beam radiated from the at least one light source;

at least one beam splitter configured to split the first light beam transmitted by the first waveguide to obtain a second light beam;

a second waveguide configured to receive the second light beam; and

a quantum dot optical amplifier provided on the second waveguide and comprising a barrier layer, a quantum dot layer, and a wetting layer, the quantum dot optical amplifier being configured to modulate a phase of the second light beam, and to amplify an intensity of the second light beam.

2. The beam steering apparatus of claim 1 , wherein the quantum dot optical amplifier further comprises a first electrode layer provided on the barrier layer and a second electrode layer provided on the wetting layer.

3. The beam steering apparatus of claim 2 , further comprising a first spacer provided between the barrier layer and the first electrode layer, and a second spacer provided between the wetting layer and the second electrode layer.

4. The beam steering apparatus of claim 1 , wherein the quantum dot optical amplifier further is configured to modulate the phase of the second light beam and amplify the intensity of the second light beam based on a current applied to the quantum dot optical amplifier, the current ranging from 0.1×I th to 1×I th , where I th is a threshold current.

5. The beam steering apparatus of claim 1 , wherein, based on a charge supply to the quantum dot optical amplifier reaching a certain level or higher, a carrier density of the quantum dot layer in a ground state is saturated and a substantially constant gain of the quantum dot optical amplifier is maintained, and

wherein, based on an increase of a carrier density of the wetting layer, the wetting layer has a refractive index that is changed, upon which the phase of the second light beam is modulated.

6. The beam steering apparatus of claim 1 , wherein the quantum dot layer comprises a Group III-V semiconductor material.

7. The beam steering apparatus of claim 1 , wherein the quantum dot layer comprises InAs.

8. The beam steering apparatus of claim 1 , wherein the wetting layer comprises In 0.15 GaAs.

9. The beam steering apparatus of claim 1 , wherein, in the quantum dot optical amplifier, the barrier layer, the quantum dot layer, and the wetting layer are repeatedly stacked 2 to 30 times.

10. The beam steering apparatus of claim 1 , further comprising an antenna provided on an end portion of the second waveguide, the second waveguide extending from the quantum dot optical amplifier.

11. A system comprising:

a beam steering apparatus comprising:

a substrate;

at least one light source provided on the substrate;

a first waveguide configured to transmit a first light beam radiated from the at least one light source;

at least one beam splitter configured to split the first light beam transmitted by the first waveguide to obtain a second light beam;

a second waveguide configured to receive the second light beam; and

a quantum dot optical amplifier provided on the second waveguide and comprising a barrier layer, a quantum dot layer, and a wetting layer, the quantum dot optical amplifier being configured to modulate a phase of the second light beam, configured to amplify an intensity of the second light beam;

a receiver configured to receive the second light beam radiated from the beam steering apparatus toward an object and reflected therefrom; and

a processor configured to classify and process a plurality of light beams irradiated toward the object in a plurality of directions based on at least one of a distribution-by-location and a distribution-by-time of the second light beam received by the receiver.

12. The system of claim 11 , wherein the quantum dot optical amplifier further comprises a first electrode layer provided on the barrier layer and a second electrode layer provided on the wetting layer.

13. The system of claim 12 , wherein the beam steering apparatus further comprises a first spacer provided between the barrier layer and the first electrode layer, and a second spacer provided between the wetting layer and the second electrode layer.

14. The system of claim 11 , wherein the quantum dot optical amplifier is further configured to modulate the phase of the second light beam and amplify the intensity of the second light beam based on a current applied to the quantum dot optical amplifier, the current ranging from 0.1×I th to 1×I th , where I th is a threshold current.

15. The system of claim 11 , wherein, based on a charge supply to the quantum dot optical amplifier reaching a certain level or higher, a carrier density of the quantum dot layer in a ground state is saturated and a substantially constant gain of the quantum dot optical amplifier is maintained, and

wherein, based on an increase of a carrier density of the wetting layer, the wetting layer has a refractive index that is changed, upon which the phase of the second light beam is modulated.

16. The system of claim 11 , wherein the quantum dot layer comprises a Group III-V semiconductor material.

17. The system of claim 11 , wherein the quantum dot layer comprises InAs.

18. The system of claim 11 , wherein the wetting layer comprises In 0.15 GaAs.

19. The system of claim 11 , wherein, in the quantum dot optical amplifier, the barrier layer, the quantum dot layer, and the wetting layer are repeatedly stacked 2 to 30 times.