公开(公告)号：US3624553A

公开(公告)日：1971-11-30

申请号：US3624553D

申请日：1969-10-06

Applicant: BELL TELEPHONE LABOR INC

Inventor： TRAN NGUYEN VAN

IPC: H01S5/30 ,  H01S3/18

CPC classification number: H01S5/30 ,  H01S5/3223

Abstract: There is disclosed a cyclotron resonance laser of the type in which the Landau-level ladder is truncated either by the optical phonon or unequal spacings of the levels, in which the semiconductive crystal consists essentially of P-type germanium nearly compensated with antimony and in which, typically at low temperatures, the only effective acceptor level is a zinc energy level so deep in the band gap that the population inversion can be established by pumping radiation at 10.6 microns or 9.6 microns by a carbon dioxide molecular laser. In order to reduce the effective mass of heavy holes and to avoid reabsorption of the stimulated radiation by transitions between the heavy-hole and light-hole bands, suitable pressure, for example, uniaxial pressure, splits the heavy-hole and light-hole bands by about 0.02 electron volts.

公开(公告)号：US3461403A

公开(公告)日：1969-08-12

申请号：US3461403D

申请日：1967-12-13

Applicant: BELL TELEPHONE LABOR INC

Inventor： PATEL CHANDRA K N ,  TRAN NGUYEN VAN

IPC: G02F1/39

CPC classification number: G02F1/39

公开(公告)号：US3617764A

公开(公告)日：1971-11-02

申请号：US3617764D

申请日：1969-05-06

Applicant: BELL TELEPHONE LABOR INC

Inventor： PATEL CHANDRA K ,  TRAN NGUYEN VAN

IPC: G02F1/35 ,  G02F1/39 ,  H03F7/04

CPC classification number: G02F1/3534 ,  G02F1/39

Abstract: A phase-matched tunable millimeter wave or far infrared wave generator or mixer employs semiconductor active media having large bound-electron second-order nonlinear effects but which, in particular instances, are not sufficiently birefringent to be phase-matchable by conventional techniques. There is generated a linearly polarized difference-frequency wave for which free carriers (electrons or holes) have the effect of subtracting an appreciable amount from the index of refraction determining its propagation constant. The linearly polarized wave is generated in crystals of the active medium when the frequencies of a pair of input radiations to be mixed and a tuning condition, such as the magnitude of magnetic field applied transversely to the direction of propagation of the input radiations, are appropriately selected. Also, in a parametric oscillator, one radiation is supplied and a second radiation relatively closely spaced in frequency is highly resonated, the frequency of the second radiation and the difference frequency being variable by variation of the magnetic field magnitude.