CN101493412B - Measurement method and apparatus for infrared light modulation photoluminescence spectrum - Google Patents

Abstract

The invention discloses a method for modulating photoluminescence spectrum by infrared light and a device thereof. The device comprises a Fourier transform infrared spectrum measurement system, a laser system as a pumping and detection light source, a phase-locking amplifier and a low pass filter which couple a detector and a circuit control panel in a Fourier transform infrared spectrometer, and two choppers which are arranged on an optical path between a test sample and the laser system. The method is characterized by performing measurement of light-modulated photoluminescence spectrum by the device, and being capable of accurately determining energy position of a plurality of optical transitions in photoluminescence signals. The infrared modulated photoluminescence spectrum is a physical differential of the photoluminescence spectrum, and can accurately analyze luminescence process, thus being capable of being used as a reliable and effective means for measuring photoluminescence signals related to a multi-optical transition mechanism. The method and the device have the advantages of rapid and convenient properties, and are applicable to detection of weak luminescence properties of infrared semiconductor photoelectric materials containing impurities and defects.

Description

A kind of measuring method of infrared light modulation photoluminescence spectrum and device

Technical field:

The present invention relates to a kind of infrared semiconductor photoelectric material measuring technology, specifically, mainly be based on measuring method and device that the step-scan function of fourier-transform infrared (FTIR) spectrometer is carried out the photoabsorption modulation light photoluminescence.

Background technology:

(Photoluminescence, PL) spectrum is widely used in the research of semiconductor material optical property and physical process as a kind of effective nondestructiving detecting means to photoluminescence, has promoted the understanding to the associated materials characteristic.The PL spectrographic technique not only can disclose the information of electronic band structure aspects such as material band gap, band edge attitude, can also be used for the research for material impurity and defective etc.

For the low dimensional structures sample of molecular beam epitaxy (MBE) and metal organic chemical deposition method growth, sample is more even, and mass ratio is better, and the full width at half maximum of the PL signal of acquisition is narrow, basic corresponding a kind of optical transition of the single glow peak in the PL signal.For example, for GaInP/AlGaInP MQW sample, the full width at half maximum of PL signal is less than 10meV under 1.8K.At this moment, utilize 600-700nm band Fourier transform photoluminescence spectrum measuring method and device (patent No.: ZL 200610023426.4), can obtain the PL spectrum of high s/n ratio.For in the low energy gap, far-infrared material, the for example mercury cadmium telluride (Hg of MBE growth _1-xCd _xTe) sample utilizes the method and apparatus (patent No.: ZL 200610023133.6) based on the infrared-modulated photoluminescence spectrum measuring of step-scan, can effectively eliminate the room temperature radiation, significantly improves detection sensitivity, obtains the PL spectrum of high s/n ratio.Yet for the mercury cadmium telluride sample, impurity wherein and defective have bigger influence to the PL signal of material.For example, for the Hg of component x=0.235 _1-xCd _xTe sample, the glow peak full width at half maximum under the 77K in the PL signal comprising the contribution of multiple optical transition, are confirmed relatively difficulty to corresponding transition mechanism greater than 20meV.Use linear fit method to confirm the number and the corresponding level of energy of corresponding transition traditionally, thereby judge corresponding optical transition mechanism.But because in advance and do not know that the PL signal comprises optical transition between the different energy levels of how many kinds of actually, the linear match of carrying out by this often has very big uncertainty.The derivative spectral method has been proved to be to solve a kind of of this type problem maybe approach.Through derivation operation is learned in spectrum peek, all kinds of optical transition that often can clear view take place in the sample, thus confirm corresponding transition energy, lay the foundation for carrying out correlative study.But the mathematics differential is limited by spectral signal-noise ratio, and corresponding mathematics smoothing process causes losing of trickle spectral signature inevitably.If can realize modulator approach through physical means; Directly obtain the physics derivative spectrum of PL spectrum; Be optical modulation photoluminescence spectrum (Photomodulated Photoluminescence; PMPL), can more reliably obtain the number and the corresponding transition energy of optical transition, this is definite particularly effective for weak signal transition energy in the PL spectrum of specimen.

Summary of the invention:

In sum; How to overcome existing modulation PL spectrographic technique and cause PL difficulty that spectrum faces at the close many transition processs of analysing energy based on the FTIR spectrometer; Directly measure different transition process PL glow peak corresponding energy through physics differential means; It is key technical problem to be solved by this invention; Therefore, the object of the present invention is to provide a kind of PMPL spectrographic technique and device thereof of the infrared Fourier transform based on step-scan, enable to realize the physics differential; Significantly improve the sensitivity of differentiating many transition processs and reliability, strengthen the accuracy of definite optical transition energy, thereby a kind of effective way is provided for the spectral analysis of infrared semiconductor material.

According to a kind of photoabsorption modulation light photoluminescence spectral apparatus of the present invention, comprising based on step-scan:

One Optical Maser System, it comprises laser instrument and external beam splitter, it produces the two-way continuous laser; One FFIR measuring system; It has Fourier transformation infrared spectrometer and control desk computing machine; Constitute the interference of light parts of light path, detector and this computing machine CC control panel that these interference of light parts connect with the luminous signal of specimen;-optic modulating device; It comprises into the first lock-in amplifier 2-1, the second lock-in amplifier 2-3 and the first chopper 2-2, the first chopper 2-4 that circuit connects; Chopper forms modulated pumping and exploring laser light with the two bundle continuous laser copped waves that this Optical Maser System sends; Two bundle modulated lasers through the first chopper 2-2 and the second chopper 2-4 are incident to specimen and the variation that produces infrared PL signal and PL signal intensity, and this two bundles modulated laser is also as the input end of their reference signals of reference signal feed-in of the first lock-in amplifier 2-1, the second lock-in amplifier 2-3 in addition.The signal input part of the second lock-in amplifier 2-3 connects the output terminal of detector; A road of the second lock-in amplifier 2-3 output terminal is connected with the input end of low-pass filter; Another road of the second lock-in amplifier 2-3 output terminal is connected with the input end of the first lock-in amplifier 2-1; The output terminal of the first lock-in amplifier 2-1 is connected with the input end of circuit control panel.

Described first and second lock-in amplifiers are Standford SR830 DSP type lock-in amplifier; Described first and second choppers are Standford SR540 type mechanical chopper; Described laser instrument is Spectra-Physics 2065 type Argon ion lasers; Described fourier-transform infrared spectrometer is a BrukerIFS 66v/S type FTIR spectrometer; And described specimen is all infrared semiconductor materials, for example HgCdTe material.

The core of technical conceive of the present invention is to use to be had continuously and the FTIR spectrometer of step-scan function, also comprises assemblies such as Optical Maser System, chopper and binary channels lock-in amplifier.Pumping laser is through external beam splitter, the semi-transparent semi-reflecting two-way laser that becomes.The two-way laser of transmission and reflection is modulated into sine wave through chopper respectively, shines on the specimen, produces the variation of PL signal and PL signal intensity respectively.The modulating frequency of while chopper signal as a reference enters into corresponding lock-in amplifier.The signal that is sent by specimen converts electric signal into via detector, the feed-in second lock-in amplifier 2-3.One tunnel feed-in low-pass filter 103 of second lock-in amplifier 2-3 output obtains PL signal (I _PL); Another road feed-in first lock-in amplifier 2-1 obtains optical modulation PL signal (Δ I _PL).Then two paths of signals is outputed to circuit control panel, obtain PMPL spectrum (Δ I through Fourier transform at last _PLWith I _PLRatio).Compare with modulation PL spectrographic technique, utilize the PMPL spectrographic technique can obtain to modulate the variation two paths of signals of PL signal and PL signal intensity simultaneously, and then obtain the PMPL spectrum of sample based on the FTIR step-scan.With respect to modulation PL spectrum, PMPL spectrum can effectively be removed the undesired signal in the spectrum, accurately confirms the transition energy position of a plurality of optical transition in the PL signal.

Through selecting the photovoltaic or the light waveguide type Te-Cd-Hg detector of KBr beam splitter and liquid nitrogen refrigerating, can realize measurement to 1.3～10 μ m or 9～22 mu m waveband scope PMPL spectrum.

According to inventive concept, a kind of infrared light modulation photoluminescence spectrum method of the present invention based on the step-scan Fourier transformation infrared spectrometer, its step comprises:

S1, in the reflection of laser and transmitted light path, insert two choppers, realize to the pump light that incides specimen with survey light and carry out amplitude modulation(PAM); And between the detector of Fourier transformation infrared spectrometer and circuit control panel, insert corresponding two lock-in amplifiers, carry out phase-sensitive detection;

S2, Fourier transformation infrared spectrometer is placed the step-scan state; Suitably choose the sensitivity of the modulating frequency of two choppers, two lock-in amplifiers and sample integral time the variation that begins to measure infrared modulation photoluminescence signal and photoluminescence signal;

The variation of S3, photoluminescence signal and photoluminescence signal outputs to the circuit control panel of Fourier transformation infrared spectrometer; Then get into the control desk computing machine; Obtain the photoabsorption modulation light photoluminescence spectrum information of all wave bands at one time, shorten the spectra collection required time.

In addition, described specimen is all infrared semiconductor materials, for example HgCdTe material.

Great advantage of the present invention is:

1, detection sensitivity high, be very beneficial for infrared band photoelectric semiconductor material feature measurement, especially pointing out for various optical transitions under the PL signal broad situation;

2, the same time obtains the spectral information that all wave band PMPL signals change, and experimental period shortens;

3, have benefited from the well-separated of Fourier transform frequency and Laser Modulation frequency; Lock-in amplifier sampling time constant to choose the upper limit no longer limited; Therefore both simple and easy to do, can guarantee high as far as possible spectrum signal to noise ratio (S/N ratio) again, be particularly advantageous in detection to weak light semiconductor material PMPL process.

Description of drawings:

Fig. 1 has provided the synoptic diagram of the experimental provision of optical modulation photoluminescence spectrum (PMPL) measurement.1 is the FFIR measuring system among the figure, and 1-1 is a Fourier transformation infrared spectrometer, the 101st, and interference of light parts, the 102nd, detector, the 103rd, low-pass filter, the 104th, circuit control panel, 1-2 are the control desk computing machines; 2 is optic modulating devices among the figure, and 2-1 is first lock-in amplifier, and 2-3 is second lock-in amplifier, and 2-2 is that first chopper and 2-4 are second choppers; 3 is Optical Maser Systems among the figure, and 3-1 is a laser instrument, and 3-2 is external beam splitter; The 4th, specimen.

Fig. 2 has provided the outline flowchart that optical modulation photoluminescence spectrum (PMPL) is measured.

Embodiment:

Provide better embodiment of the present invention according to Fig. 1 and Fig. 2 below, and describe in detail, technical characterictic of the present invention and functional characteristics can be described better, rather than be used for limiting scope of the present invention.

Specific embodiments is as shown in Figure 1, and photoabsorption modulation light photoluminescence spectrometry device comprises-the external beam splitter 3-2 of laser instrument 3-1 emitting laser bundle process, the semi-transparent semi-reflecting two-way laser that becomes; Between this spectrometer 1-1, sample 4 and control desk computing machine 1-2, insert the first lock-in amplifier 2-1 and the second lock-in amplifier 2-3 in the optic modulating device 2; And be incident at the two-way laser that Optical Maser System 3 sends on the path of specimen 4 the first chopper 2-2 and the second chopper 2-4 are set, make it to form the modulation incident laser.More particularly, step-scan photoabsorption modulation light photoluminescence spectrometry device of the present invention comprises-Optical Maser System 3, and wherein laser instrument 3-1 produces continuous laser, and external beam splitter 3-2 is with semi-transparent semi-reflecting pumping and the detection two bundle laser of becoming of laser beam;-FFIR system 1; Have Fourier transformation infrared spectrometer 1-1 and control desk computing machine 1-2 on it; Accept the interferometer component 101 of the PL signal of specimen 4; The detector of sending into behind signal process interferometer component 101 Fourier transforms 102, and the circuit control panel 104 that is connected with this computing machine 1-2;-optic modulating device 2; It comprises into the first lock-in amplifier 2-1, the second lock-in amplifier 2-3 and the first chopper 2-2, the second chopper 2-4 that circuit connects; The first chopper 2-2, the second chopper 2-4 lay respectively at through between the two-way laser and specimen 4 behind the external beam splitter 3-2; Continuous laser is modulated into modulated laser incides the PL signal intensity is changed, the modulating frequency of two-way modulated laser is the reference signal input end of the signal feed-in first lock-in amplifier 2-1 and the second lock-in amplifier 2-3 as a reference also.The input end of the second lock-in amplifier 2-3 connects detector 102, and its output terminal connects the input end of the low-pass filter 103 and the first lock-in amplifier 2-1 respectively, the output terminal CC control panel 104 of the first lock-in amplifier 2-1.

Its test philosophy-as shown in Figure 1 has used the first chopper 2-2, the second chopper 2-4 and the first lock-in amplifier 2-1, the second lock-in amplifier 2-3, the frequency (Ω of the first chopper 2-2 ₁) and the frequency (Ω of the second chopper 2-4 ₂) satisfy Ω ₁＜＜Ω ₂The signal that gets into the second lock-in amplifier 2-3 does

I ^d(δ)＝I _1，PL(δ)sinΩ ₁t+I _2，PL(δ)sinΩ ₂t+δI _PL(δ)sinΩ ₁t·sinΩ ₂t (1)

The PL signal that three on the right produces with pumping laser respectively in the formula, the PL signal that exploring laser light light produces, pump light is relevant with the variation of the PL signal intensity that the detection photoconduction causes.The output signal of detector is through the AC coupling feed-in second lock-in amplifier 2-3, and signal times is with the reference signal u of the phase-sensitive detection device of the second lock-in amplifier 2-3 then _Ref2Sin Ω ₂T,

$I^{\mathrm{LIA}2}\left(\mathrm{\&delta;}\right)=u_{\mathrm{Ref}2}{K}_{\mathrm{AC}}^{\mathrm{LIA}2}[I_{1,\mathrm{PL}}\left(\mathrm{\&delta;}\right)\sin {\mathrm{\&Omega;}}_{1}t\&CenterDot;\sin {\mathrm{\&Omega;}}_{2}t+\frac{1}{2}{\mathrm{<figure-callout\; id="2"\; label="I"\; filenames="H2009100469954E00011.png"\; state="\{\{state\}\}">I</figure-callout>}}_{2,\mathrm{PL}}\left(\mathrm{\&delta;}\right)-\frac{1}{2}{\mathrm{<figure-callout\; id="2"\; label="I"\; filenames="H2009100469954E00011.png"\; state="\{\{state\}\}">I</figure-callout>}}_{2,\mathrm{PL}}\left(\mathrm{\&delta;}\right)\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="H2009100469954E00011.png"\; state="\{\{state\}\}">cos</figure-callout>}2{\mathrm{\&Omega;}}_{2}t$ (2)

$+\frac{\mathrm{\&Delta;}{I}_{\mathrm{PL}}\left(\mathrm{\&delta;}\right)}{2}\sin {\mathrm{\&Omega;}}_{1}t(1-\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="H2009100469954E00011.png"\; state="\{\{state\}\}">cos</figure-callout>}2{\mathrm{\&Omega;}}_{2}t)]$

The DC of leading up to of output signal is coupled into low-pass filter (0＜Ω＜Ω ₁), obtaining direct-flow output signal is (～I _PL)

$I_{\mathrm{DC}}\left(\mathrm{\&delta;}\right)=\frac{u_{\mathrm{Ref}2}{K}_{\mathrm{AC}}^{\mathrm{LIA}2}{K}_{\mathrm{DC}}}{2}{\mathrm{<figure-callout\; id="2"\; label="I"\; filenames="H2009100469954E00011.png"\; state="\{\{state\}\}">I</figure-callout>}}_{2,\mathrm{PL}}\left(\mathrm{\&delta;}\right),$ $B_{\mathrm{DC}}\left(\mathrm{\&sigma;}\right)=\frac{u_{\mathrm{Ref}2}{K}_{\mathrm{AC}}^{\mathrm{LIA}2}{K}_{\mathrm{DC}}}{2}{\mathrm{<figure-callout\; id="2"\; label="B"\; filenames="H2009100469954E00011.png"\; state="\{\{state\}\}">B</figure-callout>}}_{2,\mathrm{PL}}\left(\mathrm{\&sigma;}\right)---\left(3\right)$

Through selecting reasonable time constant τ, satisfy Ω ₁＜Ω＜Ω ₂, just can filtered signal in Ω ₂With 2 Ω ₂Composition.Another road of output signal is through the AC coupling feed-in first lock-in amplifier 2-1, and signal does

$I^{\mathrm{LIA}2}\left(\mathrm{\&delta;}\right)=u_{\mathrm{Ref}2}{K}_{\mathrm{AC}}^{\mathrm{LIA}2}[\frac{1}{2}{\mathrm{<figure-callout\; id="2"\; label="I"\; filenames="H2009100469954E00011.png"\; state="\{\{state\}\}">I</figure-callout>}}_{2,\mathrm{PL}}\left(\mathrm{\&delta;}\right)+\frac{\mathrm{\&Delta;}{I}_{\mathrm{PL}}\left(\mathrm{\&delta;}\right)}{2}\sin {\mathrm{\&Omega;}}_{1}t]---\left(4\right)$

Signal times is with the reference signal u of the phase-sensitive detection device of the first lock-in amplifier 2-1 then _Ref1Sin Ω ₁t

$I^{\mathrm{LIA}1}\left(\mathrm{\&delta;}\right)=u_{\mathrm{Ref}2}{u}_{\mathrm{Ref}1}{K}_{\mathrm{AC}}^{\mathrm{LIA}2}{K}_{\mathrm{AC}}^{\mathrm{LIA}1}[\frac{1}{2}{\mathrm{<figure-callout\; id="2"\; label="I"\; filenames="H2009100469954E00011.png"\; state="\{\{state\}\}">I</figure-callout>}}_{2,\mathrm{PL}}\left(\mathrm{\&delta;}\right)\sin {\mathrm{\&Omega;}}_{1}t+\frac{\mathrm{\&Delta;}{I}_{\mathrm{PL}}\left(\mathrm{\&delta;}\right)}{2}(\frac{1}{2}-\frac{1}{2}\mathrm{<figure-callout\; id="2"\; label="cos"\; filenames="H2009100469954E00011.png"\; state="\{\{state\}\}">cos</figure-callout>}2{\mathrm{\&Omega;}}_{1}t)]---\left(5\right)$

Through selecting reasonable time constant τ, satisfy 0＜Ω＜Ω ₁And guarantee than big difference, just can filtered signal in Ω ₁With 2 Ω ₁Composition.The signal that gets into circuit control panel at last does

$I^{\mathrm{LIA}1}\left(\mathrm{\&delta;}\right)=\frac{u_{\mathrm{Ref}2}{u}_{\mathrm{Ref}1}{K}_{\mathrm{AC}}^{\mathrm{LIA}2}{K}_{\mathrm{AC}}^{\mathrm{LIA}1}}{4}\mathrm{\&Delta;}{P}_{\mathrm{PL}}\left(\mathrm{\&delta;}\right)---\left(6\right)$

In the frequency range of being considered,

and

can be used as constant.The spectrum that obtains through Fourier transform does

$B_{\mathrm{AC}}^{\mathrm{LIA}}\left(\mathrm{\&sigma;}\right)=\frac{u_{\mathrm{Ref}2}{u}_{\mathrm{Ref}1}{K}_{\mathrm{AC}}^{\mathrm{LIA}2}{K}_{\mathrm{AC}}^{\mathrm{LIA}1}}{4}\mathrm{\&Delta;}{B}_{\mathrm{PL}}\left(\mathrm{\&sigma;}\right)---\left(7\right)$

Formula the right is the variation (～Δ B of PL signal _PL), i.e. optical modulation PL signal.According to formula (3) and (7), we just can obtain the derivative spectrum of PL signal, i.e. optical modulation photoluminescence spectrum (PMPL)

$\frac{\mathrm{\&Delta;}{\mathrm{<figure-callout\; id="2"\; label="B\; PL\; B"\; filenames="H2009100469954E00011.png"\; state="\{\{state\}\}">B</figure-callout>}}_{\mathrm{PL}}}{B_{}}=\frac{2K_{\mathrm{DC}}}{u_{\mathrm{Ref}1}{K}_{\mathrm{AC}}^{\mathrm{LIA}1}}\frac{B_{\mathrm{AC}}^{\mathrm{LIA}}\left(\mathrm{\&sigma;}\right)}{B_{\mathrm{DC}}\left(\mathrm{\&sigma;}\right)}---\left(8\right)$

We can find comprising in the PMPL spectrum based on step-scan the variation of PL spectrum, can directly judge the number of optical transition in the semiconductor material and confirm corresponding transition energy through this physics derivative spectrum.

Based on above-mentioned thinking; In the present embodiment, the first lock-in amplifier 2-1 and the second lock-in amplifier 2-3 adopt Standford SR830 DSP lock-in amplifier, the first chopper 2-2 and the second chopper 2-4 to adopt Standford SR540 mechanical chopper, laser instrument 3-1 to adopt Spectra-Physics 2065 type Argon ion lasers, FTIR spectrometer 1-1 to adopt Bruker IFS 66v/S type FTIR spectrometer to carry out the enforcement that the present invention proposes new method.Its light path is still as shown in Figure 1, has provided concise and to the point operating process among Fig. 2, and specific operation process is following:

Data are obtained: at first remove the first chopper 2-2 and the second chopper 2-4, and the electrical output signal of detector 102 is directly fed into electronic control part.FTIR spectrometer 1-1 is placed the signal monitoring state of continuous sweep, and through adjustment, optimization specimen 4 relevant portion light paths, the PL signal that FTIR spectrometer 1-1 is monitored reaches very big.Obtain PMPL spectrum then based on step-scan FTIR; The present invention is keeping under the constant prerequisite of specimen 4 relevant light paths; Move into and open the first chopper 2-2 and the second chopper 2-4; And detector 102 output signals are fed to the input end of the second lock-in amplifier 2-3 through the AC coupling, and its output signal is the input end of the feed-in first lock-in amplifier 2-1 again, and the output of the first lock-in amplifier 2-1 is received on the input channel of circuit control panel 104 of FTIR spectrometer 1-1.Set after the modulating frequency of the first chopper 2-2 and the second chopper 2-4, lock the first lock-in amplifier 2-1 and the second lock-in amplifier 2-3 respectively with its reference signal.Then; 1-1 places the step-scan state with the FTIR spectrometer, and trial run spectral scan process, suitably chooses the sensitivity of the first lock-in amplifier 2-1 and the second lock-in amplifier 2-3; Both guaranteed the unlikely appearance overload of whole scanning process, high as far as possible feeble signal amplifying power had been arranged again.Select the sampling integral time of the first lock-in amplifier 2-1 and the second lock-in amplifier 2-3, in the step-scan process, be in the lock state all the time to guarantee it.According to sampling integral time, set the FTIR spectrometer 1-1 stepping stand-by period again.Output signal with the second lock-in amplifier 2-3 is fed to low-pass filter 103 through the DC coupling simultaneously.So far, can formally begin the measurement of PMPL spectrum.

Data processing: the PMPL spectrum based on step-scan FTIR that the present invention proposes also can utilize the FTIR system to control software and accomplish Fourier transform work, therefore is convenient to implement.Can obtain the PMPL spectrum of step-scan according to equation (3), (7) and (8).

The of the present invention crucial inventive point that comprises in aspect above-mentioned two is that (1) is through carrying out amplitude modulation(PAM) to pumping and exploring laser light; And combine phase-sensitive detection technological; Detection sensitivity is high; Be very beneficial for infrared band photoelectric semiconductor material feature measurement, especially pointing out for various optical transitions under the PL signal broad situation; (2) the same time obtains the PMPL spectral information of all wave bands, strengthens the detectivity of infrared band faint optical signal, shortens the spectra collection required time; (3) utilize the step-scan function of FTIR spectrometer, eliminate the Fourier frequency, thereby loosen the harshness restriction that external modulating frequency is chosen, make infrared band PMPL spectrographic technique really feasible.

Claims (3)

1. the device of an infrared light modulation photoluminescence spectrum comprises:

-Optical Maser System (3), wherein laser instrument (3-1) produces continuous laser, and external beam splitter (3-2) is with semi-transparent semi-reflecting pumping and the detection two bundle laser of becoming of laser beam;

-FFIR measuring system (1); It has Fourier transformation infrared spectrometer (1-1) and control desk computing machine (1-2); Detector (102) with interference of light parts (101) connection in the Fourier transformation infrared spectrometer (1-1); The circuit control panel (104) that is connected with control desk computing machine (1-2), and the low-pass filter that is connected with circuit control panel (103);

-optic modulating device (2), it comprises pairing first lock-in amplifier of laser-bounce light path (2-1), first chopper (2-2) and laser-transmitting light path corresponding second lock-in amplifier (2-3), second chopper (2-4); The signal input part of second lock-in amplifier (2-3) connects the output terminal of detector (102); A road of second lock-in amplifier (2-3) output terminal is connected with the input end of low-pass filter (103); Another road of second lock-in amplifier (2-3) output terminal is connected with the input end of first lock-in amplifier (2-1); The output terminal of first lock-in amplifier (2-1) is connected with the input end of circuit control panel (104);

Pumping and exploring laser light by Optical Maser System (3) outgoing shine the interference of light device (101) that specimen (4) goes up the signal entering spectrometer that produces; First chopper (2-2), second chopper (2-4) form modulated laser with the two bundle laser copped waves that this Optical Maser System (3) sends; Two bundle modulated lasers through first chopper (2-2) and second chopper (2-4) are incident to specimen (4) and produce infrared light photoluminescence signal; Cause the photoluminescence signal intensity to change simultaneously, the chopper reference signal of modulated laser is also as the input end of their reference signals of reference signal feed-in of first lock-in amplifier (2-1), second lock-in amplifier (2-3) in addition; The variation of photoluminescence signal and photoluminescence signal intensity outputs to the circuit control panel (104) of Fourier transformation infrared spectrometer (1-1), then gets into control desk computing machine (1-2), thereby obtains the optical modulation photoluminescence spectrum of sample.

2. infrared light modulation photoluminescence spectrum device according to claim 1 is characterized in that, described specimen (4) is the infrared semiconductor material.

3. infrared light modulation photoluminescence spectrum measuring method of utilizing the said device of claim 1, its step comprises:

S1, in the reflection of laser and transmitted light path, move into two choppers, realize to the pump light that incides specimen with survey light and carry out amplitude modulation(PAM); And between the detector of Fourier transformation infrared spectrometer and circuit control panel, insert corresponding two lock-in amplifiers, carry out phase-sensitive detection;

S2, Fourier transformation infrared spectrometer is placed the step-scan state; Suitably choose the sensitivity of the modulating frequency of two choppers, two lock-in amplifiers and sample integral time the variation that begins to measure infrared modulation photoluminescence signal and photoluminescence signal;

The variation of S3, photoluminescence signal and photoluminescence signal outputs to the circuit control panel of Fourier transformation infrared spectrometer; Then get into the control desk computing machine; Obtain the photoabsorption modulation light photoluminescence spectrum information of all wave bands at one time; Be the variation of photoluminescence signal intensity and the ratio of photoluminescence signal intensity, shorten the spectra collection required time, strengthen the detectivity of infrared band feeble signal.

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