Ab initiovolume-dependent elastic and lattice dynamical properties of chalcopyriteCuGaSe2

Abstract

We report the results of a first principles study of volume-dependent elastic and lattice dynamical properties of chalcopyrite semiconductor CuGaSe 2 . The calculations have been carried out within density-functional perturbation theory framework, employing the local density functional approximation with norm-conserving pseudopotentials and a plane-wave basis set. Born effective charge tensors, dielectric permittivity tensors, the phonon frequencies at the Brillouin zone center and their Grüneisen parameters are calculated by using density functional perturbation theory while the elastic constants are calculated in metric-tensor formulation. We compared the Grüneisen parameters of the calculated quantities to those of ZnSe which is the isoelectronic analog of CuGaSe 2 and other zinc-blende-type materials and found similar trends.

Temperature dependence of band gaps in semiconductors: Electron-phonon interaction

“…Using ab initio codes Parlak et al have calculated the phonon frequencies of CuGaSe 2 at the center of the Brillouin zone. 38 Semiempirical calculations based on the adiabatic bond charge model have also been published. 39 We display in Fig.…”

Phase stability and elastic properties of CuGaSe2 under high pressure

“…However, B 0 obtained from GGA-PBE in this work is 64 GPa, while the experiment [26] reported as 71 GPa. The elastic stiffness tensor of I42d at 0 GPa is satisfy the conditions of C 11 ; C 33 ; C 44 ; C 66 4 0; C 11 4 C 12 j j; C 11 C 33 4 C 2 13 ; ðC 11 þ C 12 ÞC 33 4 2C 2 13 , which are Born stability criteria in chalcopyrite lattice [3,12]. Moreover, the elastic parameters in Table 3 satisfy Born stability criteria in all structures [23,28].…”

“…A study of elastic properties in each stable structure is significant to understand the mechanical properties of CuGaSe 2 under high pressure. We compare the elastic properties at 0 GPa with previous works [3,25] as shown in Table 3. C 11 , C 12 and C 13 from GGA-PBE are lower than other calculations, while C 33 , C 44 and C 66 are in good agreement.…”

“…The bulk modulus from DFT calculations depend on using the correlation functional and equation of state. The calculated result from LDA-PW by fitting to a third-order Vinet equation of state [3] is 84.5 GPa, while the FP-LMTO þLDA result fitting from Birch equation of state [25] is 79.97 GPa, and GGA-PBE (in VASP) result fitting from Murnaghan equation of state in Ref. [12] is 57.7 GPa.…”

“…The efficiencies of solar cells highly depend on the physical and optical properties of semiconducting materials in multilayer structures. The I-III-VI 2 ternary compounds, such as CuInSe 2 (CIS) and CuGaSe 2 (CGS), have recently emerged as a very promising material for photovoltaic solar-energy application [1][2][3][4]. Under the conditions of high-pressure and temperature, many semiconductors and their alloys undergo a solid-solid transition from a disordered to an ordered structure because the different constituent atoms tend to occupy special sites in the lattice [5,6].…”