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公开(公告)号：SE329220B
公开(公告)日：1970-10-05
申请号：SE624365
申请日：1965-05-13
Applicant: IBM
Inventor： LASHER G
Abstract: 1,071,434. Semi-conductor laser devices. INTERNATIONAL BUSINESS MACHINES CORPORATION. April 30, 1965 [May 13, 1964], No. 18240/65. Headings H1C and H1K. An injection laser is positioned contiguous with an absorber of the output of the laser such that when the energy absorbed by the absorber is reduced an increased quantity of energy is reflected back into the laser to cause the latter to emit coherent radiation. In the arrangement of Fig. 2A a gallium arsenide PN junction crystal 6 with cleaved ends 10, 11 is divided into two electrically isolated portions 12, 13 by slot 14, section 12 being biased by battery 23 to act as a light emitter below the threshold for lasing action and section 13 being biased by 23 1 to act as a light absorber. When the laser injection current is first turned on light passing into the absorber is absorbed forming a new electron hole pair which on recombination emits light in random directions. In this condition of the device the effective reflectivity of the absorber is low, Fig. 1B (not shown), and there is a high laser threshold. When a current from generator 26 is applied to contact 20, or a current pulse applied from generator 26 1 or if an external pulse of light enters the absorber or an external pulse of light travels from the laser to the absorber then the absorbtion of light in region 13 decreases and the effective reflectivity of the device increases. This causes a lowering of the laser threshold and simulated emission occurs which maintains itself after the current pulses or external light pulses terminate. The device is turned to its off state i.e. emitting spontaneous non-coherent light, by a negative trigger pulse from generator 26 or 26 1 or by an external light pulse travelling transversely through the laser 12. In the arrangement of Figs. 3A, 3B (not shown), a second non-linear absorber is added to the basic configuration shown in Fig. 2A transverse to the first absorber. This arrangement is tri-stable in so far as there are two on states when either of the absorbers are bleached and a coherent output is produced and an off state corresponding to high attenuation by the absorbers when there is no coherent output. The three portions may be cut from the same semi-conductor wafer.
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公开(公告)号：SE315348B
公开(公告)日：1969-09-29
申请号：SE1130063D
申请日：1963-10-15
Applicant: IBM
Abstract: 1,045,478. Semi-conductor lasers. INTERNATIONAL BUSINESS MACHINES CORPORATION. Oct. 14, 1963 [Oct. 15, 1962], No. 40363/63. Heading H1K. [Also in Division H3] Charge carriers are injected into a body of direct band gap material at a rate sufficient to stimulate emission of radiation due to recombination of the carriers. A semi-conductor body consists of GaAs with a PN junction formed by diffusion between zinc and tellurium doped regions. A gold and antimony plated washer is attached to one side of the device and an indium contact is applied to the other side. The device is operated at low temperatures, e.g. 25‹ K or 77‹ K. Details of many such devices, and their performance, are given in the Specification, together with several modifications. In one device, cadmium replaces zinc as a dopant, a nickel washer soldered with tin being used as one contact, and an InGaAs alloy as the other. A second device uses a gold-plated MoHg washer as one contact and tin or evaporated gold as the other. A further device is undoped on one side of the junction. Other suitable semi-conductor materials include GaSb, InSb, InP, InAs and GaAs-GaP alloys. Charge carrier injection may be achieved by using a magnetic rectifier structure or a semi-conductor-metal junction instead of a PN junction.
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