MONOLITHIC SOLID STATE TRAVELLING WAVE TUNABLE AMPLIFIER AND OSCILLATOR

• US 3,835,407 A
• Filed: 05/21/1973
• Issued: 09/10/1974
• Est. Priority Date: 05/21/1973
• Status: Expired due to Term

• Current Assignee: Amnon Yariv, Avraham Gover
• Original Assignee: Amnon Yariv, Avraham Gover
• Inventors: Yariv, Amnon, Gover, Avraham
• Primary Examiner(s): Saalbach, Herman Karl
• Assistant Examiner(s): Mullins, James B.
• Application Number:
  US05/362,821
• Time in Patent Office: 477 Days
• Field of Search: 330/5,38R,38M,43 331/82,17R,17G
• US Class Current: 330/5
• CPC Class Codes: H03F 3/55 with semiconductor devices only

Abstract

A travelling wave amplifier of signals in the millimeter wavelength range consists of a monolithic solid state waveguide structure wherein space harmonics of the input electromagnetic energy wave (signals) are generated due to periodic corrugations of the guide'"'"''"'"'s top surface. The waveguide structure includes a current conductive layer supportive of a stream of electrons with an electron velocity ve, the stream of electrons being located where the amplitude of the spatial first harmonic is a maximum. The corrugation periodicity L is selected so that the equality ve K ( omega /2 pi ) L is satisified. In the equality, omega is the angular frequency of the input wave and K is a factor which is not less than and on the order of one.

Claims

1. A solid state travelling wave device comprising:

a substantially dielectric travelling wavEguide supportive of electromagnetic wave of an angular frequency omega 1, said dielectric waveguide being characterized by a current conductive layer therein adjacent a top surface thereof, and supportive of a stream electrons in the direction of the wave propagation through said dielectric waveguide, the electron velocity being definable as ve, the top surface of said dielectric waveguide being corrugated with a corrugation periodicity of L satisfying the equality ve K 1/2 pi L, wherein K is a factor greater than and on the order of one; and

means including a pair of electrodes in electrical contact with said conductive layer in said dielectric waveguide for controlling the electron velocity as a function of the potential difference between said electrodes.

2. The solid state travelling wave device as described in claim 1 wherein L is less than the micron range, and the thickness of said current conductive layer of said dielectric waveguide from the top surface thereof being of the order of L/2 pi .

3. The solid state travelling wave device as described in claim 1 further including input means for directing an input electromagnetic wave of an angular frequency omega 1 to said waveguide to be propagated therethrough, whereby an amplified electromagnetic wave at omega 1 exits said dielectric waveguide through an end opposite the end through which said input wave enters said waveguide as a result of energy exchange between the stream of electrons and the spatial first harmonic of said wave generated in said waveguide.

4. A solid state travelling wave amplifier comprising:

a dielectric travelling waveguide supportive of an electromagnetic wave of an angular frequency omega , and having a corrugated top surface with a corrugation periodicity definable as L;

means including a solid-state layer deposited on said corrugated top surface of said dielectric waveguide for providing a stream of electrons in said layer with an electron velocity, definable as ve, wherein ve K ( omega /2 pi )L, where K is factor greater than but on the order of one; and

input means for directing electromagnetic wave energy at an angular frequency omega , to said dielectric waveguide in a direction parallel to the electron stream.

5. The solid state travelling wave amplifier as described in claim 4 wherein the thickness of said solidstate layer is on the order of L/2 pi and L is less than one micron.

6. The solid state travelling wave amplifier as described in claim 4 wherein L is on the order of not more than a few microns, and wherein the thickness of said solid-state layer is on the order of L/2 pi .

7. In a monolithic solid state travelling wave amplifier the arrangement comprising:

a substantially dielectric travelling waveguide supportive of an electromagnetic wave of a wavelength lambda , and having a corrugated top surface extending between first and second opposite sides of said waveguide, said top surface being corrugated with a corrugation periodicity, definable as L, whereby when an electromagnetic wave propagates through said waveguide spatial harmonics of said wave are generated therein, said dielectric waveguide being characterized by a current-conductive layer included therein and extending downwardly from said top surface;

potential means coupled to said current-conductive layer for inducing an electron stream to flow in said layer in a direction parallel to said top surface in close proximity thereto with an electron velocity definable as ve, wherein K ve/c . lambda /L, where K is a factor greater than but on the order of one and c is the speed of light; and

input means for directing an electromagnetic wave of wavelength lambda to the first end of said waveguide.

8. The arrangement as described in claim 7 wherein said potential means comprise meanS for varying the electron velocity in said electron stream.

9. The arrangement as described in claim 8 wherein L is in the micron range and ve is on the order of one-tenth c and the thickness of said current conductive layer of said dielectric waveguide is of the order of L/2 pi .

10. The arrangement as described in claim 7 wherein ve is on the order of one-tenth c, L is less than 1 micron and the thickness of said current conductive layer of said dielectric waveguide is of the order of L/2 pi .