Fourier transform infrared spectroscopy approach for measurements of photoluminescence and electroluminescence in mid-infrared

Abstract

An improved Fourier transform infrared spectroscopy approach adapting to photoluminescence and electroluminescence measurements in mid-infrared has been developed, in which diode-pumped solid-state excitation lasers were adopted for photoluminescence excitation. In this approach, three different Fourier transform infrared modes of rapid scan, double modulation, and step scan were software switchable without changing the hardware or connections. The advantages and limitations of each mode were analyzed in detail. Using this approach a group of III-V and II-VI samples from near-infrared extending to mid-infrared with photoluminescence intensities in a wider range have been characterized at room temperature to demonstrate the validity and overall performances of the system. The weaker electroluminescence of quantum cascade lasers in mid-infrared band was also surveyed at different resolutions. Results show that for samples with relatively strong photoluminescence or electroluminescence out off the background, rapid scan mode is the most preferable. For weaker photoluminescence or electroluminescence overlapped with background, double modulation is the most effective mode. To get a better signal noise ratio when weaker photoluminescence or electroluminescence signal has been observed in double modulation mode, switching to step scan mode should be an advisable option despite the long data acquiring time and limited resolution.

Optical characterization of Si‐doped metamorphic InGaAs with high indium content

“…As can be seen in the Fig. (a), the RT PL spectra acquired using conventional rapid scan (RS) mode of FTIR spectrometer from these samples exhibit a clear blue‐shift as the doping concentration increases, which is similar to the previous work on the fundamental absorption edge of the n‐doped samples . It is obvious that the RT PL spectrum of the In 0.53 Ga 0.47 As layer in sample E presents one pronounced band‐to‐band emission centered at about 727 meV.…”

Structural and optical characterizations of InPBi thin films grown by molecular beam epitaxy

“…The PL and absorption spectra were measured using a Nicolet Magna 860 Fourier transform infrared (FTIR) spectrometer (Thermo Fisher Scientific Inc., Waltham, MA, USA), in which a liquid-nitrogen cooled InSb detector and a CaF 2 beam splitter were used. A diode-pumped solid-state (DPSS) laser ( λ  = 532 nm) was used as the excitation source for PL measurements, and the double modulation mode was used to eliminate the mid-infrared background radiation beyond 2 μm [12]. For the low-temperature PL measurements, the samples were mounted into a continuous-flow helium cryostat, and the temperature was controlled from 8 to 300 K by a Lake Shore 330 temperature controller (Lake Shore Cryotronics, Inc., Westerville, OH, USA).…”

InAs/In0.83Al0.17As quantum wells on GaAs substrate with type-I emission at 2.9 μm

“…Gu This work reports on InAs quantum wells (QWs) grown on GaAs-based metamorphic In 0.83 Al 0. 17 As buffers for type-I mid-infrared (MIR) emission. X-ray diffraction and Raman measurements show that the GaAs-based quantum wells have similar lattice and strain conditions with the InP-based structure.…”

“…Cross-sectional transmission electron microscopy (XTEM) images were measured by a Philips CM200 FEG microscope operating at 160 kV. The PL spectra were measured using a Nicolet Megna 860 Fourier transform infrared (FTIR) spectrometer with rapid scan mode, 17 in which liquid-nitrogen cooled InSb detector and CaF 2 beam splitter were used. A 532-nm DPSS laser was used as the excitation source.…”