We report on mid-wave infrared InAsSb photodetectors with high-barrier materials implemented in the depletion region. The devices exhibit promising performance at high temperature. At 160 K, the 50% cutoff wavelength is $4.18~\mu \text{m}$ , and the shot noise limited detectivity $D^{\star} $ is $1.57\times 10 ^{12}$ cm $\cdot $ Hz $^{1/2}$ /W for the peak wavelength of $3.79~\mu \text{m}$ . At 300 K, the 50% cutoff wavelength is $4.70~\mu \text{m}$ , and the $D^{\star} $ is $4.87\times 10 ^{9}$ cm $\cdot $ Hz $^{1/2}$ /W for the peak response wavelength of $4.15~\mu \text{m}$ . The dark current of the device is found to be dominated by the diffusion current rather than the generation-recombination current for the temperature range of 160–300 K. We also determine the Varshni parameters of the InAsSb material with varying strain, and the bandgap bowing parameters.