A device has a threshold photon energy of

PHYSICS · Multi-part · Fermi University Physics · Quantum Mechanics · Earth, Climate & Energy Physics · Origins of quantum theory

Energy from Physics, Ch The solar resource resolved: geometry, spectrum and the limits of concentration

Problem

E=1.60\,\mathrm{eV}

, one not in the chapter's list. Model the Sun at the Earth's orbit as the diluted

5772\,\mathrm{K}

blackbody with

f_\odot=2.16\times10^{-5}

. ((a)) Substitute

x=\varepsilon/k_BT_\odot

in the photon-flux integral, find the lower limit

x_0

and the prefactor, and evaluate the integral numerically to three significant figures. ((b)) Find the photon flux

\Phi(1.60\,\mathrm{eV})

and the current density it would drive at one electron per photon, and check that both lie between the chapter's values at

1.42

and

1.80\,\mathrm{eV}