Zero-Energy State: The Lande's g Value in Quantum Dotsin Al_xGai_(-x)As

摘要

The light hole g value in Al_xGa_(1-x)As is found to show scaling behavior as a function of quantum well width width)-β with β≈3. When x is varied to change the Ga concentration there is a critical value of the concentration of 1-x_o=0.88 at which the g value vanishes, g_⊥=0. There is a scaling behavior g⊥= 2[1-(1-x)/(1-x_0)]~y. The g1 data varies from about -0.42 for x=0 to 0.6 for x=0.374. Hence, the charge variations from the g values are due to a phase transition. Since, the g value goes from a negative value to a positive value, it has a point at which the value is "zero". The zero g value is also derivable from a formula, (1/2)g={1+(1/2)±S]/(21+1). For 1=0, S=1/2 the negative sign gives zero value which describes the "zero-energy state".