Minima of Conduction Band Valleys in [eV] at 300K:    Al_xGa_1-xAs                    [ref:1]

    E_g(x) =     1.424 + 1.247x                              (0 < x < 0.45)
                     1.424 + 1.247 + 1.147(x-0.45)²     (0.45 < x < 1.0)

    E_L(x) = 1.708 + 0.642x

    E_X(x) = 1.900 + 0.125 + 0.143x²
 

E(k)  Diagram :  Effective Masses for Al_xGa_1-xAs   [ref:1,  2]

    A) Conduction Band Valleys
              E_g(k) = h²k²/2m_g*   where,
                        m_g*/m₀ = 0.067 + 0.083x (for Density of States); 0.067 + 0.083x (for Conductivity)
                        k_g = 2p/a (0, 0, 0)

             E_L(k) = h²(k-k_L)²/2m_L*   where,
                        m_L*/m₀ = 0.56 + 0.1x (for DOS); 0.11 + 0.03x (for Conductivity)
                        k_L = 2p/a (1/2, 1/2, 1/2)
 

             E_X(k) = h²(k-k_X)²/2m_X*   where,
                        m_X*/m₀ = 0.85 - 0.14x (for DOS); 0.32 - 0.06x (for Conductivity)
                        k_X = 2p/a (0, 0, 1-D)
 

    B) Valence Band Valleys
             E_hh(k) = h²k²/2m_hh*   where,
                       m_hh*/m₀ = 0.62 + 0.14x

             E_lh(k) = h²k²/2m_lh*   where,
                       m_lh*/m₀ = 0.087 + 0.063x

                 E_so(k) = h²k²/2m_so*  - D_o    where,
                       m_so*/m₀ = 0.15 + 0.09x
                     D_o = 0.34 - 0.04x

    The Density of States effective mass for valence band, m_vb, is found from
                m_vb = (m_lh*^3/2 + m_hh*^3/2)^2/3
    E_so(k)  is the split-off band and does not contribute to the DOS.