CN1079598A - High power photoconductive switch pulser - Google Patents

High power photoconductive switch pulser Download PDF

Info

Publication number
CN1079598A
CN1079598A CN 92108443 CN92108443A CN1079598A CN 1079598 A CN1079598 A CN 1079598A CN 92108443 CN92108443 CN 92108443 CN 92108443 A CN92108443 A CN 92108443A CN 1079598 A CN1079598 A CN 1079598A
Authority
CN
China
Prior art keywords
transmission line
load
conductor
switching
pulse
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
CN 92108443
Other languages
Chinese (zh)
Other versions
CN1027721C (en
Inventor
顾冠清
支婷婷
陈兰荣
范滇元
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Institute of Optics and Fine Mechanics of CAS
Shanghai Micro Electronics Equipment Co Ltd
Original Assignee
Shanghai Institute of Optics and Fine Mechanics of CAS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai Institute of Optics and Fine Mechanics of CAS filed Critical Shanghai Institute of Optics and Fine Mechanics of CAS
Priority to CN 92108443 priority Critical patent/CN1027721C/en
Publication of CN1079598A publication Critical patent/CN1079598A/en
Application granted granted Critical
Publication of CN1027721C publication Critical patent/CN1027721C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Abstract

A kind of high power photoconductive switch pulser is by pulse-shaping system, switching system, load transmission line, load and laser constitution.Switching system is included in photoconductivity switching, charging capacitor and dc power supply thereof, composite controller and adjustable noninductive resistance, building-out capacitor and the dc power supply thereof that has locking-up effect under the high electric field, in parallel after charging capacitor is connected with composite controller with photoconductivity switching, be in series with building-out capacitor again.Suitably choosing electrical quantity can produce less than 100 seconds -12The square-wave pulse of before and after edge.

Description

High power photoconductive switch pulser
The invention belongs to pulse generator, is about utilizing materials such as GaAs photoconduction the pulse generator of locking-up effect to occur after the short-pulse laser excitation that is subjected to certain wavelength and energy under the high electric field.
At IEEE Transactions on Electron Devices, Vol.38 No.4.P696 in April, 1991 F.J.Zutavern etc. discloses a kind of high-power pulse generator that utilizes the GaAs photoconductive switch locking-up effect, its principle such as Fig. 1,1 is charging capacitor among the figure, charging voltage is made as V 1, 2 and 3 all is GaAs photoconductive switch, is called for short switch, 4 is that a segment length is L 1Open circuited transmission line, characteristic impedance Z 1, row ripple transmission speed is V in the line P1, as the composite controller of switch 2, the 5th, load, impedance are R L
Switch 2 is in the high electric field, and when it was triggered by a short-pulse laser (1.064 μ m), switch 2 both end voltage were reduced to latch voltage V L0, composite controller 4 is by (Z simultaneously 1(V 1-V L0))/(Z L+ R 1) the amplitude voltage charging, obtain V in the load 5 L=(R 2(V 1-V L0))/(R L+ Z 1) voltage.Capable ripple transmission time 2L through twice in the composite controller 4 1/ V P1, charging pulse is with (R 1(V 1-V L0))/(R 1+ Z L) amplitude reflected back input, and, produce (2Z in input and charging pulse stack 1(V 1-V L0))/(Z 1+ R L) amplitude voltage.Because V 1Satisfy formula: V 1=((2Z 1+ R L) (V 1-V L0))/(L), this moment V 1=((R L)/(Z 1)+2) V L0, thereby switch 2 is triggered after (2L by light pulse 1)/(V P1) time, 2 liang of terminal potentials of switch equate that voltage reduces to 0, and switch 2 enters zero electric field in moment, and wherein charge carrier begins compoundly rapidly, and returns to the high resistant normality from lock-out state very soon.Then, switch 3 is delayed the back light pulse and triggers and produce locking-up effect, and the charging pulse voltage in the composite controller 4 discharges to load 5 through switch 3 loops at this moment, and produces inverted pulse in load 5.Switch 3 returns to normality behind the discharge off.This moment, whole system was finished one-period, and waited for the triggering of next light pulse.
There is following problem in this system:
1. system effectiveness is low.In this system, electric capacity charging voltage V 1By GaAs switch 2 composite controllers 4 and load 5 dividing potential drops.This system switching operating efficiency should be: η=(V L)/(V 1) * 100%, that is: η=(R L(V 1-V L0))/((R L+ Z 1) V 1) * 100%.In the prior art, R L=Z 1=50 Ω, that is: η=(V 1-V L0)/(2V 1) * 100%, obviously η＜50%.
2. output pulse waveform is poor.Under composite controller 4 effects, switch is compound with the time of nanosecond magnitude, and pulse voltage makes zero in the nanosecond magnitude time thereupon in the load 5.Because the work of switch 3 produces reversed polarity high-amplitude discharge pulse in the load 5, reduced obtaining the back of pulse more along quality.Thereby in this system, can't produce have psec at a high speed the edge, back and pulse duration at the square wave high-voltage pulse of hundreds of psecs to number nanoseconds.
3. biswitch work not only needs two light pulses, and the synchronization delay control system between the light pulse of needs excitation two switches, system complex.In this system,, will cause electric capacity 1, burn out optical switch by the discharge of switch 2,3 heavy currents if two switches are opened by light simultaneously.
The purpose of this invention is to provide a kind of high power photoconductive switch pulser, can produce the square-wave pulse on the forward position and the edge, back of 100 psecs, it has high efficiency, requires laser energy low, safe and reliable to operation and characteristic of simple structure.
The present invention is by pulse shaping system, switching system, load transmission line, load and laser constitution.Said switching system comprises photoconductivity switching, charging capacitor and dc power supply thereof, composite controller and noninductive adjustable resistance, building-out capacitor and the dc power supply thereof with locking-up effect.In parallel after said charging capacitor is connected with composite controller with said photoconductivity switching, be in series with building-out capacitor again.Said pulse shaping system is connected with load transmission line by switching system, connects load again, and laser provides the picopulse with activation threshold value luminous energy for photoconductivity switching.
In this pulse generator, should satisfy following electricity parameter relation:
①V 1≥2V L0
②R W= (Z 1V 1)/(V 1-2V L0)
③V 2＝-V L0
④Z 1＞＞Z 0
⑤L 1＞ 1/2 L 0
Z wherein 0Characteristic impedance for load transmission line, pulse shaping system communications line;
Z 1Characteristic impedance for coaxial transmission line in the composite controller;
R WResistance for noninductive adjustable resistance;
V L0Latch voltage for photoconductivity switching;
V 1Charging valtage for charging capacitor;
V 2Be the charging voltage of building-out capacitor, its value is-V L0;
L 0Length for the transmission line of pulse shaping system;
L 1Length for the coaxial transmission line of composite controller.
There are three kinds of forms in said pulse shaping system:
1. the endless belt-shaped transmission line made of scale copper.The closed welding of ring conductor in it, outer shroud conductor two tail ends connect the inner wire of two coaxial type load transmission line respectively, two coaxial load transmission line load ends connect two loads respectively, encircle in said switching system is connected between the common place of the closed place of conductor and two load transmission line outer conductors.
Be connected in parallel after the internal and external conductor series connection of two coaxial load transmission-wire terminals and double the single load of load line characteristic impedance, can realize single load output square-wave pulse.
2. single open circuited transmission line.Strip line or coaxial line all can.In the transmission line conductor and load transmission line one conductor altogether, another conductor dbus is crossed switching system and is linked to each other with another conductor of load transmission line.
3. Bu Lumei (Blumlein) transmission line.It is made of two sections isometric transmission lines, and the conductor of a correspondence directly links to each other in two sections transmission lines, and another conductor dbus overload links to each other, and switching system is connected between Bu Lumei transmission line one end two conductors.
The invention will be further described below in conjunction with accompanying drawing.
Fig. 1 is existing high-power pulse generator schematic diagram.
Fig. 2 is the circuit block diagram that the endless belt-shaped transmission line of embodiment of the invention 1-is made the pulse shaping system.
Fig. 3 is the switching system electrical block diagram.
Fig. 4 is the pulse voltage waveform figure of embodiment 1 circuit each point.
When Fig. 5 is the embodiment of the invention 1 order one load, the connection layout of two coaxial load transmission lines order, one load.
Fig. 6 is the circuit block diagram that the single open circuited transmission line of embodiment of the invention 2-is made the pulse shaping system.
Fig. 7 is the circuit block diagram that embodiment of the invention 3-Bu Lumei transmission line is made the pulse shaping system.
Pulse generator of the present invention (referring to Fig. 2) is made up of pulse shaping system 6, switching system 9, coaxial load transmission line 11 and 17, load 12 and 15, laser 18.Pulse shaping system 6 adopts endless belt-shaped transmission line, characteristic impedance Z 0, long is L 0, ripple propagation velocity therein is V P0, obviously the transmission time is L 0/ V P0, ring conductor 7 closures in it, outer shroud conductor 8 tail ends connect the coaxial load transmission line respectively, and (characteristic impedance is Z 0) 10 the inner wire 11 and the inner wire 16 of coaxial load transmission line 17, (characteristic impedance is Z to the coaxial load transmission line 0=50 ohm) 10 and 17 outer conductor 13 and 14 at input altogether, (impedance is Z in load 0) 12 and 14 be connected on respectively between the inner wire and outer conductor of coaxial load transmission line 10 and 17 outputs.Switching system 9 is connected between the common place N of the M of closure place of ring conductor 7 in the endless belt-shaped transmission line and coaxial load transmission line outer conductor 13 and 14.
(voltage is V to switching system (referring to Fig. 3) by photoconductivity switching 2, charging capacitor 1 and dc power supply thereof 1) 19, (resistance is R to have composite controller 4 that the coaxial transmission line of characteristic impedance Z constitutes and noninductive adjustable resistance thereof W) 20, (voltage is V for building-out capacitor 22 and dc power supply thereof 2=-V L0) 21 compositions.In parallel with photoconductivity switching 2 after charging capacitor 1 is connected with composite controller 4, connecting with building-out capacitor 22 constitutes switching system again.
Photoconductivity switching 2 can adopt GaAs photoconductive switch, or undoped gallium arsenide or indium phosphide photoconductivity switching, and they have locking-up effect under High-Field, wherein the locking electric field E of pure GaAs L0Be 3.6 kv/cm, mix the locking electric field E of chromium GaAs L0Be 8 kv/cm, the locking electric field E of indium phosphide L0Be 14.4 kv/cm, when photoconductivity switching electrode gap distance was d, then corresponding latch voltage was V L0=d * E L0, minimum triggering light energy is A L0 Charging capacitor 1 and building-out capacitor 22 all are the capacity plate antennas that adopts scale copper and insulation film or pottery to fit, and have extremely low characteristic impedance r 1And r 2, r for example 1＜5 ohm, r 2＜0.2 ohm, power supply 19 gives charging capacitor 1 charging, and charging voltage is V 1, power supply 21 gives building-out capacitor 22 chargings, charging voltage V 2=-V L0The characteristic impedance Z that constitutes the coaxial transmission line of composite controller 4 is 500 ohm～1000 ohm, obviously Z 1＞＞Z 0, length is L 1, the ripple transmission speed is V therein P1
Laser 18, output wavelength are 1.06 μ m laser, and pulse duration is tens of psecs, energy (A 〉=A L0) little joule of magnitude, the laser of its output directly triggers photoconductivity switching 2.Laser also can adopt frequency doubled light (the 0.53 μ m) way of output, also can adopt the semiconductor short-pulse laser of co-wavelength.
In this pulse generator, following electrical relation is satisfied in design:
V 1≥2V L0
R W= (2V 1)/(V 1-2V L0)
V 2＝-V L0
Z 1＞＞Z 0
L 1＞ 1/2 L 0
The course of work of this pulse generator following (over time, i.e. oscillogram) referring to the voltage of Fig. 4-circuit each point, after power supply 19 and 21 is connected, V in the generator QN=-V L0, V MQ=V 1=V MK, V MN=V 1-V L0=V MC=V MD, V CN=V DN=V QK=V RS=0.
When t=0, when photoconductivity switching 2 is triggered by the laser pulse of tens of psec pulsewidths, enter lock-out state from high-impedance state rapidly, the voltage V of photoconductivity switching 2 MQFrom V 1Reduce to latch voltage V L0, this moment the latch voltage V on the photoconductivity switching 2 L0With the bucking voltage V on the building-out capacitor 22 QN=-V L0Synthetic, at the voltage V of M, N point-to-point transmission MN=0, and alternating-current resistance is approximately 0 between M, N, thereby switching system 9 presents a desirable high frequency channel, promptly switching system is opened.Simultaneously the fast wave process is stored in electric field energy in the endless belt-shaped transmission line from the two ends of endless belt-shaped transmission line 6 simultaneously rapidly by load coaxial transmission line 10 and 17 releases, voltage V MC, V MD, V CN, V DNVariation as shown in Figure 4, have V to the forward wave of 10 and 17 directions transmission CN=V DN=-1/2(V 1-V L0) voltage amplitude, the backward-wave that transmits in endless belt-shaped transmission line 6 from C, D has-1/2(V 1-V L0) voltage amplitude, this moment V MC=V MD=(V 1-V L0)-1/2(V 1-V L0)=1/2(V 1-V L0), through L 0/ V P0Time, the energy storage in the endless belt-shaped transmission line 6 all discharges, thus on load 12 and 15, all obtain to have less than 100 psec before and after edges, width is L 0/ V P0, amplitude is 1/2(V 1-V L0) square wave electric pulse.When wave process began in endless belt-shaped transmission line 6, composite controller coaxial transmission line 4 was recharged, charging incident wave voltage V QK=V 1-V L0, through L 1/ V LOTime produces reflection at adjustable resistance 20 places, and reflected wave voltage is P(V 1-V L0), wherein P is a reflecting system, P=(R W-Z 1)/(R W+ Z 1), reflected wave voltage is again through L 1/ V P1Time, i.e. t=2L 1/ L P1Constantly, V QKBecome the superposition value of incident wave voltage and reflected wave voltage.Because R WValue satisfy relational expression V 1=(2R W)/(R W-Z 1) V L0So, V QK=(1+P) (V 1-V L0)=V 1, this moment, photoconductivity switching was in V 1And V QKResultant voltage under, be in zero electric field and compound immediately, return to high-impedance state from lock-out state.Coaxial transmission line 4 charging pulses are by resistance 20 and charge circuit discharge, and endless belt-shaped transmission line is charged to V immediately simultaneously 1-V L0, when t=T, each point voltage recovers the state before the t=0, and whole pulse generator is finished one-period.Wait for that next light pulse triggers and repeat said process again, so circulate in and present a series of square wave electric pulses outputs in the load.The efficient of this pulse generator is the twice of prior art.
When adopting Fig. 5 form with the single load 23 in parallel of coaxial load transmission-wire terminal internal and external conductor serial connection back, the resultant voltage in the load 23 is V 1-V L0, pulse duration still is V L0/ V P0, load impedance is 2Z 0So the output pulse energy is constant.
Embodiment 2, as shown in Figure 6, are to adopt single open circuited transmission line to make the high power photoconductive switch pulser of pulse shaping system.It is L by length 0(L 0＜L 1), row wave speed is V P0, characteristic impedance is Z 0Single open-circuit line 24, switching system 9, load transmission line 25(characteristic impedance Z 0) and load 26(impedance Z 0) and laser 18 compositions, the coaxial transmission line length of composite controller 4 is greater than single open circuited transmission line length in the switching system.The efficient of this pulse generator and prior art identical, but it can form before and after along precipitous square-wave pulse.
Embodiment 3, as shown in Figure 7, are to adopt the Bu Lumei transmission line to make the high power photoconductive switch pulser of pulse shaping system.It is made up of Bu Lumei transmission line 27, switching system 9 and load 28 and laser 18, and switching system 9 is connected between Bu Lumei transmission line one end two conductor M, the N, N ground connection, and load is connected in the centre position of the conductor of Bu Lumei transmission line one end ground connection.Length of transmission line is 2L 0, characteristic impedance is Z 0, load impedance is 2Z 0The coaxial transmission line length of composite controller 4 is greater than the half as much again of Bu Lumei transmission line length overall in the switching system 9.The efficient of this pulse generator is with embodiment 1.
In sum, the advantage compared with prior art of the present invention is as follows:
1. the present invention is owing to have building-out capacitor and dc power supply thereof in the switching system, and switching system becomes the picosecond photoconductivity switching of an approximate ideal, has high frequency zero electricity Resistance. The switch efficiency of switch efficiency of the present invention and prior art is identical, or doubles.
2. the shaping width of the present invention by Charging transmission line determined by the length of pulse shaping transmission line, thereby can produce and have the high power electrical pulse that is lower than 100 psec forward positions and rear edge, improved especially the quality of pulse back edge.
3. the present invention is only with a GaAs photoconductive switch with locking-up effect, thereby do not need to consider to trigger the synchronous of light or postpone, simplified equipment, switch is safe and reliable, has avoided many switchs time error to cause big electric current to the destruction of discharge photoconductivity switching.
4. the introducing of composite controller terminal regulating resistance can make system at different charging voltage V1Noninductive adjustable resistance is suitably regulated in lower work, reaches RW= (Z 1V 1)/(V 1-2V L0), realize that switch is reliably compound, keep normal repetition rate work.

Claims (5)

1, a kind of high power photoconductive switch pulser is characterized in that:
1) it is by pulse shaping system, switching system, load transmission line, load and laser constitution, said pulse shaping system is connected with load transmission line by switching system, connect load again, laser provides the triggering luminous energy of picosecond pulse for the photoconductivity switching of switching system;
2) said switching system is included in photoconductivity switching, charging capacitor and dc power supply thereof, composite controller and adjustable noninductive resistance, building-out capacitor and the dc power supply thereof that has locking-up effect under the high electric field, its annexation is: in parallel after charging capacitor is connected with composite controller with said photoconductivity switching, be in series with building-out capacitor again;
3) should satisfy following electricity parameter relation:
①V 1≥2V L0
②R W= (Z 1V 1)/(V 1-2V L0)
③V 2=-V L0
④Z 1＞＞Z 0
⑤L 1＞ 1/2 L 0
Z wherein 0Characteristic impedance for load transmission line, pulse shaping system communications line;
Z 1Characteristic impedance for coaxial transmission line in the composite controller;
R WResistance for noninductive adjustable resistance;
V L0Latch voltage for photoconductivity switching;
V 1Charging voltage for charging capacitor;
V 2Be the charging voltage of building-out capacitor, its value is-V L0
L 0Length for the transmission line of pulse shaping system;
L 1Length for the coaxial transmission line of composite controller.
2, according to the pulse generator of claim 1, it is characterized in that said pulse shaping system is the endless belt-shaped transmission line that scale copper is made, the closed welding of ring conductor in it, outer shroud conductor two tail ends connect the inner wire of two coaxial load transmission lines respectively, the load end of two coaxial load transmission lines connects two loads respectively, and the closed place of ring conductor and two load transmission line outer conductors were altogether between the place in said switching system was connected on.
3,, it is characterized in that in two coaxial load transmission-wire terminals the outer conductor back single load in parallel that is connected in series according to the pulse generator of claim 2.
4, according to the pulse generator of claim 1, it is characterized in that said pulse shaping system is single open circuited transmission line, a conductor and load transmission line one conductor are altogether in this transmission line, another conductor dbus is crossed another conductor of switching system and load transmission line and is linked to each other, and the coaxial line length of composite controller is greater than single open circuited transmission line length in the switching system.
5, according to the pulse generator of claim 1, it is characterized in that said pulse shaping system is the Bu Lumei transmission line, it is made of two sections isometric transmission lines, conductor in these two sections transmission lines directly links to each other, another links to each other to the conductor dbus overload, switching system is connected between Bu Lumei transmission line one end two conductors, and the coaxial transmission line length of composite controller is greater than the half as much again of Bu Lumei transmission line length overall in the switching system.
CN 92108443 1992-06-03 1992-06-03 High power photoconductive switch pulser Expired - Fee Related CN1027721C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN 92108443 CN1027721C (en) 1992-06-03 1992-06-03 High power photoconductive switch pulser

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN 92108443 CN1027721C (en) 1992-06-03 1992-06-03 High power photoconductive switch pulser

Publications (2)

Publication Number Publication Date
CN1079598A true CN1079598A (en) 1993-12-15
CN1027721C CN1027721C (en) 1995-02-22

Family

ID=4943550

Family Applications (1)

Application Number Title Priority Date Filing Date
CN 92108443 Expired - Fee Related CN1027721C (en) 1992-06-03 1992-06-03 High power photoconductive switch pulser

Country Status (1)

Country Link
CN (1) CN1027721C (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1326324C (en) * 2004-04-02 2007-07-11 中国科学院上海微系统与信息技术研究所 Element structure utlizing photoshort circuit for generating sub-carrier lifetime guide electrical pulse

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1326324C (en) * 2004-04-02 2007-07-11 中国科学院上海微系统与信息技术研究所 Element structure utlizing photoshort circuit for generating sub-carrier lifetime guide electrical pulse

Also Published As

Publication number Publication date
CN1027721C (en) 1995-02-22

Similar Documents

Publication Publication Date Title
Nunnally High-power microwave generation using optically activated semiconductor switches
US20080036301A1 (en) Photon Initiated Marxed Modulators
JPH01192214A (en) Pulse compacter
US4888556A (en) Linear induction accelerator and pulse forming networks therefor
US5185586A (en) Method and apparatus for digital synthesis of microwaves
Lee Optical control of semiconductor closing and opening switches
CN1027721C (en) High power photoconductive switch pulser
US8373518B2 (en) Method and apparatus for digital synthesis of long multi-cycle microwave pulses
CN1042621A (en) Circuit breaker
CN1114790A (en) High power, high pulse prepetition frequency, compact, pulsed laser diode driver
CN105375905A (en) Pulse generation device and method with high repetition frequency, high voltage and subnanosecond risetime
Zucker High-power microwave generation with photoconductors
CN109687855B (en) Asynchronous trigger high-voltage pulse modulator based on IGBT
O'Connell et al. Optoelectronic microwave power amplifiers
CN216390948U (en) Bipolar pulse signal generator
CN216649656U (en) Compact high-voltage pulse switch module
Cao et al. Nanosecond inductive energy storage pulsed power system using YBCO superconductor opening switches
Rukin et al. Pulsed power accelerator technology based on solid-state semiconductor opening switches (SOS)
CN218276653U (en) Miniaturized high-voltage modulator for gyrotron traveling wave tube power module
Lai et al. 500 Hz picosecond inductive energy storage pulsed power system using a high Tc superconductor opening switch
Buttram et al. Linear induction accelerator
Zucker et al. Nanosecond switching of high power laser activated silicon switches
USH843H (en) High power RF generation with optically activated bulk GaAs devices
CN114400988A (en) Marx pulse generation circuit based on photoconductive switch and dielectric wall accelerator
CN114374380A (en) All-solid-state high-voltage pulse module switch group

Legal Events

Date Code Title Description
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C06 Publication
PB01 Publication
C14 Grant of patent or utility model
GR01 Patent grant
C19 Lapse of patent right due to non-payment of the annual fee
CF01 Termination of patent right due to non-payment of annual fee