How to Use Type II InAs/GaSb Superlattice Structure to Reach Detection Wavelength of 2–3 $\mu{\rm m}$

Abstract

The photoluminescence (PL) peak of an InAs/GaSb superlattice (SL) structure is found to be shifted from 5.8 to 4.0 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\mu{\rm m}$</tex></formula> at 77 K, when the growth temperature is lowered from 380 to 340 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$^{\circ}{\rm C}$</tex></formula> . The PL peak shift is related to In intermixing, thus some SL structures cannot reach a detection wavelength <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">${&lt;}{\rm 3}~\mu{\rm m}$</tex></formula> . Increasing the GaSb layer thickness in the SL structure is an effective way to reach a detection wavelength of 2–3 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\mu{\rm m}$</tex></formula> . A p-i-n detector with a 50% cutoff wavelength at 2.56 <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\mu{\rm m}$</tex></formula> at 77 K is demonstrated.