Recent content by Sr1

I'm actually asking about theory, not practice

Suppose we have a quantum system ##S##, an apparatus ##A##, and an observer, say Alice, ##O##. WLOG let ##S## be a spin-##1/2##particle in a state ##0.6|\uparrow\rangle+0.8|\downarrow\rangle##. The apparatus measure it in the ##\sigma_z## basis. Then the observer sees the result. According to...

ok from dirac comb model, $$\frac{\sqrt{2mE}}{\hbar}a\sim \pi,$$ then $a=0.26nm$. The remaining questions are: Do you expect the true lattice spacing to be larger or smaller than your estimate? How does this wavelength(band gap) depend on the size of the diamond?

How can we link the band gap to lattice spacing? For (a), if we purely do dimension analysis, then I would guess $$a=\frac{\hbar c}{E_g}$$. But what's the reason behind this answer, and will the true lattice spacing be larger or smaller? For (b), I guess $$\lambda=\frac{\hbar c}{E_g}$$ due to...