Analysis of Composition Dependent Structural and Vibrational Behavior of MBE Grown InAs1-x-ySbxPy Epilayers

InAs1-x-ySbxPy alloys are critical on designing high-performance optoelectronics to operate in the 2–4 𝜇m mid-wavelength infrared (MWIR) range for biomedical diagnostics, optical communications and environmental monitoring. If grown lattice-matched to readily available GaAs-based substrates, they offer tunable bandgaps by minimizing strain-induced defects for improving efficiency of bendable nano-/micro-electronics at higher temperatures. InAs1-x-ySbxPy/GaAs heterostructures are particularly effective allowing strong confinement of electrons and holes to increase carrier capture efficiency, preventing thermal escape for high quality MWIR operations. Very few structural and vibrational studies are known for InAs1-x-ySbxPy films. Phonons play crucial role in assessing the electronic, and optical traits as they impact on carrier transport, thermal conductivity, and optical emission/absorption in various photonic devices. Gas source MBE method is used to prepare high-quality InAs1-x-ySbxPy epilayers on GaAs. The alloys suffer from immiscibility issues when As composition becomes less than < 0.4. Systematic structural and lattice dynamical properties are reported experimentally by using synchrotron extended x-ray absorption fine structure and high-resolution Fourier transform infrared reflectivity. Methodical simulations have provided valuable information on nearest-neighbor bond-lengths and the vibrational characteristics of InAs1-x-ySbxPy alloys.