Abstract There is disclosed an injected carrier device for deflecting a guided beam of radiation, such as the 10.6 micron beam from a conventional carbon dioxide laser. The waveguide structure comprises a lightly doped gallium arsenide thin film formed on a lower refractive index aluminum gallium arsenide substrate. Free charge carriers are selectively injected into a localized region of the film laterally displaced from the center of the path of the beam therein. Sufficient densities of carriers are injected either optically or electrically to cause the beam to deflect within the plane of the film away from the localized region. Deflection angles of the order of 1* to 2* and response times as short as 6 nanoseconds have been experimentally obtained with the device.
The apparatus of claim 1 in which said carrier injecting means comprises a source of at least one beam of optical radiation for optically pumping said localized region of said film, said pumping beam having a photon energy exceeding the bandgap energy of the semiconductive material of said film.
Claim 2
Dependent Claim
30 words
The apparatus of claim 2 in which the semiconductive material of said film consists essentially of gallium arsenide and the material of said substrate consists essentially of aluminum gallium arsenide.
Claim 3
Dependent Claim
29 words
The apparatus of claim 3 in which the beam to be deflected has a wavelength of the order of 10 microns in the infrared portion of the electromagnetic spectrum.
Claim 4
Dependent Claim
105 words
The apparatus of claim 1 in which said substrate is formed of a semiconductive material of one conductivity type and said carrier injecting means comprises a contacting layer of a semiconductive material of the other conductivity type formed on the major surface of said film opposite to said substrate, said contacting layer having an index of refraction less than that of said film, and means for applying a forward bias voltage between at least one localized region of said contacting layer and said substrate to inject electrically into the localized region of said film a sufficient density of free charge carriers to deflect the beam.
Claim 5
Dependent Claim
35 words
The apparatus of claim 5 in which the semiconductive material of said film consists essentially of gallium arsenide and the semiconductive material of said substrate and said contacting layer consists essentially of aluminum gallium arsenide.
Claim 6
Dependent Claim
29 words
The apparatus of claim 6 in which the beam to be deflected has a wavelength of the order of 10 microns in the infrared portion of the electromagnetic spectrum.
Claim 7
Dependent Claim
52 words
The apparatus of claim 1 in which said carrier injecting means injects a sufficient density of carriers into two elongated, spaced apart localized regions of said film disposed on opposite sides of the path of the beam therein to confine the beam in the area of said film between said localized regions.