AlGaAs/GaAs photovoltaic converters of tritium radioluminescent-lamp radiation

Electrical supply sources based on photovoltaic converters and tritium radioluminescent lamps with blue and green glow are developed and fabricated. Al$_{x}$Ga$_{1-x}$As $p$–$n$ heterostructures with various band-gap widths ($E_g$ = 1.4–1.9 eV) and compositions of the active region ($x$ = 0.1–0.35) are prepared by low-temperature liquid-phase epitaxy. The photovoltaic converter with an area of $S$ = 0.12 cm$^2$ upon irradiation by a green tritium lamp (wavelength $\lambda$ = 550 nm) has the short-circuit current density 180 nA/cm$^2$ and output electrical power $>$ 100 nW/cm$^2$.