Application Note — Real-World Applications — Notes

Application	Device/Technology	How PH-01 Concept Is Used
Solar cells (photovoltaic)	Silicon/GaAs p-n junction cells	Photons with hν > φ eject electrons creating photocurrent; efficiency depends on work function matching solar spectrum
Photodiodes & phototransistors	Optical sensors, fiber optic receivers	Incident photons generate electron-hole pairs; $current \propto photon$ flux (intensity)
Image sensors $\frac{CCD}{CMOS}$	Digital cameras, smartphones	Photoelectric effect converts photon → electron; each pixel accumulates charge proportional to light intensity
Photomultiplier tubes (PMT)	Gamma-ray detectors, PET scans, telescopes	Cascade photoelectric + secondary emission amplification; detect single photons
Burglar alarms (photoelectric sensors)	Security systems	IR photon beam → photoelectric current; broken beam triggers alarm
X-ray photoelectron spectroscopy (XPS)	Material science, chemistry	X-ray photons eject core electrons; KE of ejected electrons reveals binding energies of elements
Night vision cameras	Military, security	IR photons → photoelectron emission from photocathode

Application	Technology	How λ = $\frac{h}{p}$ Is Used
Electron microscope $\frac{TEM}{SEM}$	Biology, materials science	λ_e ≈ 0.004 nm at 100 kV (vs λ_visible ≈ 500 nm); resolution 10,000× better than light microscope
Electron diffraction $\frac{LEED}{RHEED}$	Surface science	Electrons diffract from crystal lattices; crystal structure determination
Neutron diffraction	Nuclear physics, crystallography	λ_neutron ≈ 1 Å at thermal energies; probes atomic positions without damaging samples
Atom interferometry	Inertial navigation, gravitational wave detectors	Matter waves of cold atoms create interference patterns; extreme precision measurement