Near infrared photoluminescence observed in dilute GaSbBi alloys grown by liquid phase epitaxy

We report the first observation of photoluminescence (PL) from the dilute bismide alloy GaSbBi. Epitaxial layers are grown by liquid phase epitaxy technique onto GaSb (1 0 0) substrates and PL is obtained in the near infrared spectral range (λ ∼ 1.6 μm). Incorporation of 0.2, 0.3 and 0.4 at% Bi to the layer results in a decrease of band gap energy up to 40 meV as well as an increase of luminescence from the sample. Structural analysis confirms the successful incorporation of Bi consistent with an increase in lattice parameter. Raman spectroscopy measurements indicate vibrational modes due to GaBi as well as to free Bi atoms residing at interstitial spaces.

► Using L.P.E technique we have grown GaSbBi layers with good crystallinity. ► This GaSbBi layers containing upto 0.8 at% Bi. ► 4 K PL exhibit a band gap reduction of up to 40 meV in GaSbBi.