In laser science, regenerative amplification is a process used to generate short but strong pulses of laser light. It is based on a pulse trapped in a laser resonator, which stays in there until it extracts all of the energy stored in the amplification medium. Pulse trapping and dumping is done using a polarizer and a Pockels cell, which acts like a quarter wave-plate.
When a pulse with vertical polarization is reflected off the polarizer, after a double pass through the Pockels cell it will become horizontally polarized and will be transmitted by the polarizer. After a double pass through the amplification medium, having the same horizontal polarization, the pulse will be transmitted by the polarizer. If a voltage is applied to the Pockels cell, a double pass through it will change the polarization of the pulse to vertical, so the pulse will be reflected off the polarizer and will exit the cavity. If no voltage is applied, then a double pass through the Pockels cell will not change the polarization and the pulse will get trapped inside the cavity of the resonator. The pulse can stay in the cavity until it reaches saturation or until it extracts most of the energy stored in the gain medium. When the pulse will achieve a high amplification, a second voltage can be applied to the Pockels cell in order to release the pulse from the resonator.
Radio frequency operationedit
Regenerative amplifier can also operate at Radio Frequency,[1] using the feedback between the transistor's source and gate to transform a capacitive impedance on the transistor's source to a negative resistance on its gate. Compared to voltage-gated amplifiers, this "negative resistance amplifier" will only require a tiny amount of power to achieve high gain.
^Qian, C; Duan, Q; Dodd, S; Koretsky, A; Murphy-Boesch, J (2016). "Sensitivity Enhancement of an Inductively Coupled Local Detector Using a HEMT-based Current Amplifier". Magnetic Resonance in Medicine. 75 (6): 2573–2578. doi:10.1002/mrm.25850. PMC4720591. PMID 26192998.
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regenerative, amplification, confused, with, regenerative, circuit, this, article, needs, additional, citations, verification, please, help, improve, this, article, adding, citations, reliable, sources, unsourced, material, challenged, removed, find, sources, . Not to be confused with regenerative circuit This article needs additional citations for verification Please help improve this article by adding citations to reliable sources Unsourced material may be challenged and removed Find sources Regenerative amplification news newspapers books scholar JSTOR April 2016 Learn how and when to remove this message In laser science regenerative amplification is a process used to generate short but strong pulses of laser light It is based on a pulse trapped in a laser resonator which stays in there until it extracts all of the energy stored in the amplification medium Pulse trapping and dumping is done using a polarizer and a Pockels cell which acts like a quarter wave plate Contents 1 Operating principle 1 1 Radio frequency operation 2 See also 3 References 4 External linksOperating principle editWhen a pulse with vertical polarization is reflected off the polarizer after a double pass through the Pockels cell it will become horizontally polarized and will be transmitted by the polarizer After a double pass through the amplification medium having the same horizontal polarization the pulse will be transmitted by the polarizer If a voltage is applied to the Pockels cell a double pass through it will change the polarization of the pulse to vertical so the pulse will be reflected off the polarizer and will exit the cavity If no voltage is applied then a double pass through the Pockels cell will not change the polarization and the pulse will get trapped inside the cavity of the resonator The pulse can stay in the cavity until it reaches saturation or until it extracts most of the energy stored in the gain medium When the pulse will achieve a high amplification a second voltage can be applied to the Pockels cell in order to release the pulse from the resonator Radio frequency operation edit Regenerative amplifier can also operate at Radio Frequency 1 using the feedback between the transistor s source and gate to transform a capacitive impedance on the transistor s source to a negative resistance on its gate Compared to voltage gated amplifiers this negative resistance amplifier will only require a tiny amount of power to achieve high gain See also editChirped pulse amplification Gain switching Modelocking Optical amplifier Q switching Raman amplificationReferences edit Qian C Duan Q Dodd S Koretsky A Murphy Boesch J 2016 Sensitivity Enhancement of an Inductively Coupled Local Detector Using a HEMT based Current Amplifier Magnetic Resonance in Medicine 75 6 2573 2578 doi 10 1002 mrm 25850 PMC 4720591 PMID 26192998 External links editRP Photonics encyclopedia article nbsp This optics related article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Regenerative amplification amp oldid 1188363039, wikipedia, wiki, book, books, library,
