US3746879A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Superlattice harmonic generator & mixer for electromagnetic waves
Assignee: International Business Machines Corp
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Filing: 1972-05-25
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Granted: 1973-07-17
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Expires: 1992-05-25
Abstract
Abstract The disclosure relates to a device for generating electromagnetic waves which have wavelengths different from an input wavelength to the device. The device consists of man-made superlattice structure fabricated by epitaxial deposition techniques to which at least one electromagnetic wave is applied. The input wave has an electric field component parallel to the longitudinal axis of the superlattice structure. Because of the special characteristic of the superlattice structure, it is possible to obtain as outputs all the odd harmonics of the input wavelength. By applying an electric field parallel to the longitudinal axis of the superlattice, it is possible to obtain both odd and even harmonics of the input wavelength. By switching the electric field, a gating action is obtained. To select the desired harmonic, appropriate filters are used. Mixing as well as harmonic generation is possible with the arrangements disclosed by applying a plurality of input wavelengths which by multiple photon processes produce outputs having relatively long wavelengths compared to the input wavelength. The mixed outputs in both the presence and absence of an applied electric field are obtainable by filtering. Thus, inputs in the visible range may be mixed to provide outputs in the far infrared region which are not easily obtainable using prior art arrangements.
Inventors
- 👤 L Esaki
- 👤 R Tsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 00:48
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/35; G02F1/353; G02F1/3534
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
176 words
A device for generating electromagnetic waves having wavelengths different from at least an input wavelength comprising: an artificial semiconductor superlattice structure having a given longitudinal axis, said superlattice structure comprising a body of semiconductor material at least a portion of which is a superlattice structure having at least 10 layers of semiconductor material, the first and alternate layers thereof having a given band-edge energy, the second and alternate layers thereof having a band-edge energy different from said given band-edge energy and forming with said first and alternate layers at least five spatial periods, the width of each period being less than the mean free path of a carrier along the direction of the said longitudinal axis, and having an upper bound of the order of 500A, and means for applying at least an electromagnetic wave of at least a single wavelength to said structure at least a substantial component of the electric field of said electromagnetic wave being parallel to said axis to produce a plurality of wavelengths different from said at least an input wavelength.
Claim 2
Independent Claim
176 words
A device for generating electromagnetic waves having wavelengths different from at least an input wavelength comprising: an artificial semiconductor superlattice structure having a given longitudinal axis, said superlattice structure comprising a body of semiconductor material at least a portion of which is a superlattice structure having at least 10 layers of semiconductor material, the first and alternate layers thereof having a given band-edge energy, the second and alternate layers thereof having a band-edge energy different from said given band-edge energy and forming with said first and alternate layers at least five spatial periods, the width of each period being less than the mean free path of a carrier along the direction of the said longitudinal axis, and having an upper bound of the order of 500A, and means for applying at least an electromagnetic wave of at least a single wavelength to said structure at least a substantial component of the electric field of said electromagnetic wave being parallel to said axis to produce a plurality of wavelengths different from said at least an input wavelength.
Claim 3
Dependent Claim
50 words
A device according to claim 1 further including means for applying an electric field to said structure said field having a component in a direction parallel to said longitudinal axis to produce said plurality of wavelengths and an additional plurality of wavelengths different from said at least an input wavelength.
Claim 4
Dependent Claim
19 words
A device according to claim 1 further including means for selecting at least one of said plurality of wavelengths.
Claim 5
Dependent Claim
21 words
A device according to claim 1 wherein said plurality of wavelengths are odd harmonics of said at least an input wavelength.
Claim 6
Dependent Claim
25 words
A device according to claim 1 wherein the frequency of said at least an electromagnetic wave is below the fundamental absorption gap of said semIconductor.
Claim 7
Dependent Claim
45 words
A device according to claim 1 wherein said means for applying at least an electromagnetic wave includes at least a source of electromagnetic waves and means disposed in electromagnetically coupled relationship with said structure for guiding said at least an electromagnetic wave into said superlattice.
Claim 8
Dependent Claim
66 words
A device according to claim 1 wherein said means for applying at least an electromagnetic wave includes means for simultaneously applying a plurality of waves to said structure at least a component of the electric field of each of said plurality of waves being parallel to said axis to produce at least mixtures of said plurality of waves and odd harmonics of said plurality of waves.
Claim 9
Dependent Claim
23 words
A device according to claim 2 further including means for selecting at least one of said plurality and said additional plurality of wavelengths.
Claim 10
Dependent Claim
29 words
A device according to claim 2 wherein said plurality of wavelengths and said additional plurality of wavelengths are odd and even harmonics of said at least an input wavelength.
Claim 11
Dependent Claim
48 words
A device according to claim 2 wherein said means for applying an electric field include a source of d.c. voltage, one terminal thereof being electrically connected to said superlattice, and a transparent electrode disposed on said superlattice connected to the other terminal of said source of d.c. voltage.
Claim 12
Dependent Claim
46 words
A device according to claim 6 wherein said means for guiding includes an input grating and an output grating disposed in juxtaposition with said structure such that said at least an electromagnetic wave propagates in said superlattice with the electric field thereof parallel to said axis.
Claim 13
Dependent Claim
47 words
A device according to claim 7 further including menas for applying an electric field to said structure said field having a component in a direction parallel to said axis to produce mixtures of said plurality of wavelengths and odd and even harmonics of said plurality of wavelengths.
Claim 14
Dependent Claim
17 words
A device according to claim 10 wherein said d.c. voltage source is a variable source of voltage.
Claim 15
Dependent Claim
43 words
A device according to claim 12 wherein said means for simultaneously applying a plurality of waves includes a plurality of sources of electromagnetic waves and means disposed in electromagnetically coupled relationship with said structure for guiding said plurality of waves into said superlattice.
Claim 16
Dependent Claim
22 words
A device according to claim 13 further including means connected to said d.c. voltage source for pulsing said source on and off.
Claim 17
Dependent Claim
30 words
A device according to claim 14 wherein said means for guiding includes a plurality of partially transmitting, partially reflecting elements disposed between said at least a source and said superlattice.
Claim 18
Dependent Claim
44 words
A device according to claim 14 wherein said means for guiding includes an input grating and an output grating disposed in juxtaposition with said structure such that said plurality of waves propagates in said superlattice with the electric fields thereof parallel to said axis.
Claim 19
Independent Claim
231 words
A device for generating electromagnetic waves having output wavelengths different from an input wavelength comprising: an artificial semiconductor superlattice structure having a given longitudinal axis, said superlattice structure comprising a body of semiconductor material at least a portion of which is a superlattice structure having at least 10 layers of semiconductor material, the first and alternate layers thereof having a given band-edge energy, the second and alternate layers thereof having a band-edge energy different from said given band-edge energy and forming with said first and alternate layers at least five spatial periods, the width of each period being less than the mean free path of a carrier along the direction of said longitudinal axis, and having an upper bound of the order of 500A, means for applying a plurality of electromagnetic waves to said structure at least a substantial component of the electric field of each of said plurality of waves being parallel to said given axis, means foR applying a pulsed electric field to said structure said field being parallel to said given axis, and, means electromagnetically coupled to said superlattice for selecting one of a plurality of odd harmonics of said input waves and mixtures of said input waves, when said electric field is off and a plurality of odd and even harmonics of said input wave and mixtures of said input waves when said electric field is on.
Claim 20
Independent Claim
231 words
A device for generating electromagnetic waves having output wavelengths different from an input wavelength comprising: an artificial semiconductor superlattice structure having a given longitudinal axis, said superlattice structure comprising a body of semiconductor material at least a portion of which is a superlattice structure having at least 10 layers of semiconductor material, the first and alternate layers thereof having a given band-edge energy, the second and alternate layers thereof having a band-edge energy different from said given band-edge energy and forming with said first and alternate layers at least five spatial periods, the width of each period being less than the mean free path of a carrier along the direction of said longitudinal axis, and having an upper bound of the order of 500A, means for applying a plurality of electromagnetic waves to said structure at least a substantial component of the electric field of each of said plurality of waves being parallel to said given axis, means foR applying a pulsed electric field to said structure said field being parallel to said given axis, and, means electromagnetically coupled to said superlattice for selecting one of a plurality of odd harmonics of said input waves and mixtures of said input waves, when said electric field is off and a plurality of odd and even harmonics of said input wave and mixtures of said input waves when said electric field is on.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-16 | 1977-01-15 | 1977-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-16 | 1981-01-15 | 1981-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-16 | 1985-01-15 | 1985-07-17 | $7700.00 | Window Closed / Lapsed |