Infrared photoluminescence spectra measurements using boxcar integrator in the active baseline subtraction mode

Abstract

A photoluminescence (PL) measurement method using boxcar integration in the active baseline subtraction mode has been implemented. It allows for infrared PL measurements with a low duty cycle of the pump pulse, thereby minimizing the uncontrolled heating of the structure under study. The implemented method was compared to phase-sensitive detection by signal-to-noise ratio of the resulting spectra, indicating its superior performance at low duty cycles. The decrease in uncontrolled heating of the structure under study was confirmed by observing a change in the ratio of temperature-sensitive PL peaks of a test InSb/InAs/InGaAs/InAlAs/GaAs nanoheterostructure.

Molecular beam epitaxy of GaSb on vicinal Si(001) substrates: influence of the conditions of layer nucleation on their structural and optical properties

“…The table shows the average values for two dimensions. Photoluminescence spectra were measured at 10 K on an installation based on the Vertex 80 infrared Fourier spectrometer equipped with a KBr beam splitter and an InSb photodetector cooled with liquid nitrogen [34]. A laser diode with a wavelength of 809 nm was used to excite luminescence.…”

Accurate Signal Conditioning for Pulsed-Current Synchronous Measurements

“…Figure 5a shows 25 µA current pulses with durations ∆t = 4 µs (red trace) and ∆t = 5 µs (green trace), i.e., with PRF = 350 Hz and D.C. = 0.14%, and PRF = 360 Hz and D.C. = 0.18%, respectively. The displayed I rms values were calculated according to Equations ( 8) and (10) after the acquisition of more than 10 4 pulses. The calculated mean values (34.997 nA and 45.020 nA for the 4 and 5 µs pulses, respectively) are in excellent agreement with those expected for the sourced signals.…”

“…Lock-in amplification is generally exploited as the most typical synchronous demodulation method allowing for high signal-to-noise ratio and good time resolution [ 3 , 4 ]. Gated integrator (GI), also known as “boxcar” [ 5 , 6 ], is a key approach to measure repetitive pulsed signals, and have already demonstrated its effectiveness in both laser beam [ 7 ] and X-ray [ 8 ] diagnostics, as well as in photoluminescence spectroscopy [ 9 , 10 ].…”

“…Figure 7. Rms current and charge-per-pulse calculated according to Equations (8) and(10) for pulses generated by the Keithley 6221 at 360 Hz. The effect of Δt not exactly equal to 4 µs is corrected by the 6221 instrument by adjusting the peak amplitudes on 9 pulses to give the programmed mean value of the effective current (red dashed line).…”

Молекулярно-лучевая эпитаксия GaSb на вицинальных подложках Si(001): влияние условий зарождения слоев на их структурные и оптические свойства

“…В таблице приведены средние значения по двум измерениям. Спектры фотолюминесценции измерялись при 10 K на установке на базе инфракрасного фурье-спектрометра Vertex 80, оснащенного KBr-светоделителем и InSb-фотодетектором, охлаждаемым жидким азотом [34]. Для возбуждения люминесценции был использован лазерный диод с длиной волны излучения 809 нм.…”