1. As a very rough approximation, an electron in a quantum dot can be thought of

Question

1. As a very rough approximation, an electron in a quantum dot can be thought of as an electron in a 3D box. By analogy to the 2D box, write down an expression for the energy levels fir an electron in a 3D box (write an expression for the special case of a cubic box, with all sides having a length L).

2. Consider a transition from the ground state: nx=1, ny=1, nz=1 to the excited state nx=2, ny=2, nz=1. What are the dimensions of a cubic quantum dot if the wavelength of light absorbed is 570 nm?

3. How would this wavelength differ if excitation is from the ground state to nx=1, ny=2, nz=2?

Explanation / Answer

1) For 3 D box

E=h2(n2x+n2y+n2z) /8mL2

2) given lambda = 570 nm

So E = hc/570 = 2.18 ev = 3.488 x 10-19 J = (6.65 x10-34)2(9-3)/8mL2

L = 0.01 fm

Related Questions

Navigate

• Browse (All)
• Browse 1
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.